1,421 research outputs found

    A systematic review and meta-analysis of the effectiveness of antiseptics for meatal cleaning in the prevention of catheter associated urinary tract infections

    Get PDF
    Background: Catheter-associated urinary tract infections (CAUTIs) are among the most common healthcare-associated infections. Antiseptic cleaning of the meatal area before and during catheter use may reduce the risk of CAUTIs. Aim: To undertake a systematic review of the literature and meta-analysis of studies investigating the effectiveness of antiseptic cleaning before urinary catheter insertion and during catheter use for prevention of CAUTIs. Methods: Electronic databases were searched to identify randomized controlled trials. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated and compared across intervention and control groups using DerSimonian–Laird random-effects model. Subgroup analyses were performed. Heterogeneity was estimated using the I2 statistic. Findings: In total, 2665 potential papers were identified; of these, 14 studies were eligible for inclusion. There was no difference in the incidence of CAUTIs when comparing antiseptic and non-antiseptic agents (pooled OR 0.90, 95% CI 0.73–1.10; P=0.31), or when comparing different agents: povidone-iodine vs routine care; povidone-iodine vs soap and water; chlorhexidine vs water; povidone-iodine vs saline; povidone-iodine vs water; and green soap and water vs routine care (P > 0.05 for all). Comparison of an antibacterial agent with routine care indicated near significance (P=0.06). There was no evidence of heterogeneity (I2=0%; P > 0.05). Subgroup analyses showed no difference in the incidence of CAUTIs in terms of country, setting, risk of bias, sex and frequency of administration. Conclusions: There were no differences in CAUTI rates, although methodological issues hamper generalizability of this finding. Antibacterial agents may prove to be significant in a well-conducted study. The present results provide good evidence to inform infection control guidelines in catheter management

    Mid-infrared Imaging of a Circumstellar Disk Around HR 4796: Mapping the Debris of Planetary Formation

    Get PDF
    We report the discovery of a circumstellar disk around the young A0 star, HR 4796, in thermal infrared imaging carried out at the W.M. Keck Observatory. By fitting a model of the emission from a flat dusty disk to an image at lambda=20.8 microns, we derive a disk inclination, i = 72 +6/-9 deg from face on, with the long axis of emission at PA 28 +/-6 deg. The intensity of emission does not decrease with radius as expected for circumstellar disks but increases outward from the star, peaking near both ends of the elongated structure. We simulate this appearance by varying the inner radius in our model and find an inner hole in the disk with radius R_in = 55+/-15 AU. This value corresponds to the radial distance of our own Kuiper belt and may suggest a source of dust in the collision of cometesimals. By contrast with the appearance at 20.8 microns, excess emission at lambda = 12.5 microns is faint and concentrated at the stellar position. Similar emission is also detected at 20.8 microns in residual subtraction of the best-fit model from the image. The intensity and ratio of flux densities at the two wavelengths could be accounted for by a tenuous dust component that is confined within a few AU of the star with mean temperature of a few hundred degrees K, similar to that of zodiacal dust in our own solar system. The morphology of dust emission from HR 4796 (age 10 Myr) suggests that its disk is in a transitional planet-forming stage, between that of massive gaseous proto-stellar disks and more tenuous debris disks such as the one detected around Vega.Comment: 9 pages, 4 figures as LaTex manuscript and postscript files in gzipped tar file. Accepted for publication in Astrophysical Journal Letters. http://upenn5.hep.upenn.edu/~davidk/hr4796.htm

    Acoustic Properties of Soybeans

    Get PDF
    Acoustic transmission and impact force response methods were investigated for classification of soybeans. The transmission method was slow and not suitable for real-time application. A polynomial was fitted to the deconvolved frequency spectrum of acoustic impulse data for soybeans. The curve fitting procedure successfully predicted the mass of each soybean. The size of soybeans was related to the bandwidth. Diseased soybeans consistently showed narrower bandwidths than healthy soybeans. The diseased and damaged soybeans had broad variations in low frequency which was quantifiable by threshholding the error of fit in the curve fitting procedure

    A Single Circumbinary Disk in the HD 98800 Quadruple System

    Get PDF
    We present sub-arcsecond thermal infrared imaging of HD 98800, a young quadruple system composed of a pair of low-mass spectroscopic binaries separated by 0.8'' (38 AU), each with a K-dwarf primary. Images at wavelengths ranging from 5 to 24.5 microns show unequivocally that the optically fainter binary, HD 98800B, is the sole source of a comparatively large infrared excess upon which a silicate emission feature is superposed. The excess is detected only at wavelengths of 7.9 microns and longer, peaks at 25 microns, and has a best-fit black-body temperature of 150 K, indicating that most of the dust lies at distances greater than the orbital separation of the spectroscopic binary. We estimate the radial extent of the dust with a disk model that approximates radiation from the spectroscopic binary as a single source of equivalent luminosity. Given the data, the most-likely values of disk properties in the ranges considered are R_in = 5.0 +/- 2.5 AU, DeltaR = 13+/-8 AU, lambda_0 = 2(+4/-1.5) microns, gamma = 0+/-2.5, and sigma_total = 16+/-3 AU^2, where R_in is the inner radius, DeltaR is the radial extent of the disk, lambda_0 is the effective grain size, gamma is the radial power-law exponent of the optical depth, tau, and sigma_total is the total cross-section of the grains. The range of implied disk masses is 0.001--0.1 times that of the moon. These results show that, for a wide range of possible disk properties, a circumbinary disk is far more likely than a narrow ring.Comment: 11 page Latex manuscript with 3 postscript figures. Accepted for publication in Astrophysical Journal Letters. Postscript version of complete paper also available at http://www.hep.upenn.edu/PORG/web/papers/koerner00a.p

    A search for L dwarf binary systems

    Get PDF
    We present analysis of HST Planetary Camera images of twenty L dwarfs identified in the course of the Two Micron All-Sky Survey. Four of the targets have faint, red companions at separations between 0.07 and 0.29 arcseconds (1.6 to 7.6 AU). In three cases, the bolometric magnitudes of the components differ by less than 0.3 magnitudes. Since the cooling rate for brown dwarfs is a strong function of mass, similarity in luminosities implies comparable masses. The faint component in the 2M0850 system, however, is over 1.3 magnitudes fainter than the primary in the I-band, and ~0.8 magnitudes fainter in M(bol). Indeed, 2M0850B is ~0.8 magnitudes fainter in I than the lowest luminosity L dwarf currently known, while the absolute magnitude we deduce at J is almost identical with M_J for Gl 229B. Theoretical models indicate a mass ratio of \~0.75. The mean separation of the L dwarf binaries in the current sample is smaller by a factor of two than amongst M dwarfs. We discuss the implications of these results for the temperature scale in the L/T transition region and for the binary frequency amongst L dwarfs.Comment: 38 pages, 11 figures; accepted for A

    Exciton diffusion length and charge extraction yield in organic bilayer solar cells

    Get PDF
    A method for resolving the diffusion length of excitons and the extraction yield of charge carriers is presented based on the performance of organic bilayer solar cells and careful modeling. The technique uses a simultaneous variation of the absorber thickness and the excitation wavelength. Rigorously differing solar cell structures as well as independent photoluminescence quenching measurements give consistent results

    Effectiveness and Safety of COPD Maintenance Therapy with Tiotropium/Olodaterol versus LABA/ICS in a US Claims Database

    Get PDF
    Malaltia pulmonar obstructiva crònica; Corticosteroides; OlodaterolEnfermedad pulmonar obstructiva crónica; Corticosteroides; OlodaterolChronic obstructive pulmonary disease; Corticosteroids; OlodaterolIntroduction In patients with chronic obstructive pulmonary disease (COPD), treatment with long-acting muscarinic antagonist (LAMA)/long-acting β2-agonist (LABA) combination therapy significantly improves lung function versus LABA/inhaled corticosteroid (ICS). To investigate whether LAMA/LABA could provide better clinical outcomes than LABA/ICS, this non-interventional database study assessed the risk of COPD exacerbations, pneumonia, and escalation to triple therapy in patients with COPD initiating maintenance therapy with tiotropium/olodaterol versus any LABA/ICS combination. Methods Administrative healthcare claims and laboratory results data from the US HealthCore Integrated Research DatabaseSM were evaluated for patients with COPD initiating tiotropium/olodaterol versus LABA/ICS treatment (January 2013–March 2019). Patients were aged at least 40 years with a diagnosis of COPD (but not asthma) at cohort entry. A Cox proportional hazard regression model was used (as-treated analysis) to assess risk of COPD exacerbation, community-acquired pneumonia, and escalation to triple therapy, both individually and as a combined risk of any one of these events. Potential imbalance of confounding factors between cohorts was handled using fine stratification, reweighting, and trimming by exposure propensity score (high-dimensional); subgroup analyses were conducted on the basis of blood eosinophil levels and exacerbation history. Results The total population consisted of 61,985 patients (tiotropium/olodaterol n = 2684; LABA/ICS n = 59,301); after reweighting, the total was 42,953 patients (tiotropium/olodaterol n = 2600; LABA/ICS n = 40,353; mean age 65 years; female 54.5%). Patients treated with tiotropium/olodaterol versus LABA/ICS experienced a reduction in the risk of COPD exacerbations (adjusted hazard ratio 0.76 [95% confidence interval 0.68, 0.85]), pneumonia (0.74 [0.57, 0.97]), escalation to triple therapy (0.22 [0.19, 0.26]), and any one of these events (0.45 [0.41, 0.49]); the combined risk was similar irrespective of baseline eosinophils and exacerbation history. Conclusions In patients with COPD, tiotropium/olodaterol was associated with a lower risk of COPD exacerbations, pneumonia, and escalation to triple therapy versus LABA/ICS, both individually and in combination; the combined risk was reduced irrespective of baseline eosinophils or exacerbation history.Support for this project and the journal’s Open Access Fee were funded by Boehringer Ingelheim International GmbH. No Rapid Service Fee was received by the journal for the publication of this article

    H_2 Emission From Disks Around Herbig Ae and T Tauri Stars

    Get PDF
    We present the initial results of a deep ISO-SWS survey for the low J pure rotational emission lines of H2 toward a number of Herbig Ae and T Tauri stars. The objects are selected to be as isolated as possible from molecular clouds, with a spectral energy distribution characteristic of a circumstellar disk. For most of them the presence of a disk has been established directly by millimeter interferometry. The S (1) line is detected in most sources with a peak flux of 0.3-1 Jy. The S(0) line is definitely seen in 2 objects: GG Tau and HD 163296. The observations suggest the presence of "warm" gas at T_(kin) ≈ 100 K with a mass of a few % of the total gas+ dust mass, derived assuming a gas-to-dust ratio of 100:1. The S(1) peak flux does not show a strong correlation with spectral type of the central star or continuum flux at 1.3 millimeter. Possible origins for the warm gas seen in H_2 are discussed, and comparisons with model calculations are made

    Analysis of Ωc∗(css)\Omega_c^*(css) and Ωb∗(bss)\Omega_b^*(bss) with QCD sum rules

    Full text link
    In this article, we calculate the masses and residues of the heavy baryons Ωc∗(css)\Omega_c^*(css) and Ωb∗(bss)\Omega_b^*(bss) with spin-parity 3/2+{3/2}^+ with the QCD sum rules. The numerical values are compatible with experimental data and other theoretical estimations.Comment: 13 pages, 8 figures, slight versio
    • …
    corecore