965 research outputs found

    Bronchialkarzinom-Screening mittels Niedrigdosis-CT:eine Perspektive für die Zukunft? Prävalenz- und Inzidenzergebnisse einer Machbarkeitsstudie an 817 asymptomatischen starken Rauchern

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    Da Symptome gerade in den prognostisch günstigeren Frühstadien des BC fehlen, erscheint die Untersuchung asymptomatischer Risikopatienten (Raucher) sinnvoll. Die Niedrigdosis-CT verbindet eine hohe Sensitivität mit einer geringen Strahlenbelastung. In der Münsteraner Studie wurden 817 Probanden über 7 Jahre mittels Niedrigdosis-CT untersucht. Dabei wurden BC-prävalenz und -inzidenz, Tumorstadien, -größe und -histologie, Resektionsraten sowie der Anteil an unnötigen invasiven diagnostischen Eingriffen und Intervallkarzinomen ermittelt. 96 Prozent der diagnostizierten Lungenrundherde waren benigne, BC-prävalenz und-inzidenz betrugen 1,3 und 0,86 Prozent. Stadienverteilung und Resektionsraten konnten deutlich verbessert werden, der Anteil an Intervallkarzinomen und unnötigen Eingriffen war niedrig. Grenzen bestanden in der Diagnostik von endobronchialen und hilären Tumoren. Über eine Senkung der BC- Mortalität kann mit dem einarmigen Studiendesign keine Aussage getroffen werden

    Superconductivity and hybrid soft modes in TiSe2_2

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    The competition between superconductivity and other ground states of solids is one of the challenging topics in condensed matter physics. Apart from high-temperature superconductors [1,2] this interplay also plays a central role in the layered transition-metal dichalcogenides, where superconductivity is stabilized by suppressing charge-density-wave order to zero temperature by intercalation [3] or applied pressure [4-7]. 1T-TiSe2_2 forms a prime example, featuring superconducting domes on intercalation as well as under applied pressure. Here, we present high energy-resolution inelastic x-ray scattering measurements of the CDW soft phonon mode in intercalated Cux_xTiSe2_2 and pressurized 1T-TiSe2_2 along with detailed ab-initio calculations for the lattice dynamical properties and phonon-mediated superconductivity. We find that the intercalation-induced superconductivity can be explained by a solely phonon-mediated pairing mechanism, while this is not possible for the superconducting phase under pressure. We argue that a hybridization of phonon and exciton modes in the pairing mechanism is necessary to explain the full observed temperature-pressure-intercalation phase diagram. These results indicate that 1T-TiSe2_2 under pressure is close to the elusive state of the excitonic insulator

    Hard-core Yukawa model for two-dimensional charge stabilized colloids

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    The hyper-netted chain (HNC) and Percus-Yevick (PY) approximations are used to study the phase diagram of a simple hard-core Yukawa model of charge-stabilized colloidal particles in a two-dimensional system. We calculate the static structure factor and the pair distribution function over a wide range of parameters. Using the statics correlation functions we present an estimate for the liquid-solid phase diagram for the wide range of the parameters.Comment: 7 pages, 9figure

    Bezlotoxumab: A Novel Agent for the Prevention of Recurrent Clostridium difficile Infection

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    During the past decade, the incidence and severity of Clostridium difficile infection (CDI) have significantly increased, leading to a rise in CDI-associated hospitalizations, health care costs, and mortality. Although treatment options exist for CDI, recurrence is frequent following treatment. Furthermore, patients with at least one CDI recurrence are at an increased risk of developing additional recurrences. A novel approach to the prevention of recurrent CDI is the use of monoclonal antibodies directed against the toxins responsible for CDI as an adjunct to antibiotic treatment. Bezlotoxumab, a human monoclonal antibody that binds and neutralizes C. difficile toxin B, is the first therapeutic agent to receive United States Food and Drug Administration approval for the prevention of CDI recurrence. Clinical studies have demonstrated superior efficacy of bezlotoxumab in adults receiving antibiotic therapy for CDI compared with antibiotic therapy alone for the prevention of CDI recurrence. Bezlotoxumab was well tolerated in clinical trials, with the most common adverse effects being nausea, vomiting, fatigue, pyrexia, headache, and diarrhea. The demonstrated efficacy, safety, and characteristics of bezlotoxumab present an advance in prevention of CDI recurrence

    Comparing non-safety with safety device sharps injury incidence data from two different occupational surveillance systems

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    The United States Occupational Safety and Health Administration (OSHA) Bloodborne Pathogens Standard as amended by the Needlestick Safety and Prevention Act requiring the use of safety-engineered medical devices to prevent needlesticks and sharps injuries has been in place since 2001. Injury changes over time include differences between those from non-safety compared with safety-engineered medical devices. This research compares two US occupational incident surveillance systems to determine whether these data can be generalized to other facilities and other countries either with legislation in place or considering developing national policies for the prevention of sharps injuries among healthcare personnel

    Order and nFl Behavior in UCu4Pd

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    We have studied the role of disorder in the non-Fermi liquid system UCu4Pd using annealing as a control parameter. Measurement of the lattice parameter indicates that this procedure increases the crystallographic order by rearranging the Pd atoms from the 16e to the 4c sites. We find that the low temperature properties depend strongly on annealing. Whereas the non-Fermi liquid behavior in the specific heat can be observed over a larger temperature range after annealing, the clear non-Fermi liquid behavior of the resistivity of the unannealed sample below 10 K disappears. We come to the conclusion that this argues against the Kondo disorder model as an explanation for the non-Fermi liquid properties of both as-prepared and annealed UCu4Pd

    Very High Resolution Solar X-ray Imaging Using Diffractive Optics

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    This paper describes the development of X-ray diffractive optics for imaging solar flares with better than 0.1 arcsec angular resolution. X-ray images with this resolution of the \geq10 MK plasma in solar active regions and solar flares would allow the cross-sectional area of magnetic loops to be resolved and the coronal flare energy release region itself to be probed. The objective of this work is to obtain X-ray images in the iron-line complex at 6.7 keV observed during solar flares with an angular resolution as fine as 0.1 arcsec - over an order of magnitude finer than is now possible. This line emission is from highly ionized iron atoms, primarily Fe xxv, in the hottest flare plasma at temperatures in excess of \approx10 MK. It provides information on the flare morphology, the iron abundance, and the distribution of the hot plasma. Studying how this plasma is heated to such high temperatures in such short times during solar flares is of critical importance in understanding these powerful transient events, one of the major objectives of solar physics. We describe the design, fabrication, and testing of phase zone plate X-ray lenses with focal lengths of \approx100 m at these energies that would be capable of achieving these objectives. We show how such lenses could be included on a two-spacecraft formation-flying mission with the lenses on the spacecraft closest to the Sun and an X-ray imaging array on the second spacecraft in the focal plane \approx100 m away. High resolution X-ray images could be obtained when the two spacecraft are aligned with the region of interest on the Sun. Requirements and constraints for the control of the two spacecraft are discussed together with the overall feasibility of such a formation-flying mission
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