3,413 research outputs found

    Surface roughness and flexural strength of laminated In-Ceram/Vitadur Alpha porcelain

    Get PDF
    Abstract no. 366published_or_final_versio

    Retroperitoneal schwannoma: A common tumour in an uncommon site

    Get PDF
    We describe a female adult patient who presented with acute retention of urine and vague abdominal discomfort. A provisional diagnosis of ovarian tumour was made after crosssectional imaging. At laparotomy a very large retroperitoneal mass was biopsied and found to be a schwannoma after pathological examination. The clinical, radiological, and pathological features of this disease are discussed in this report.published_or_final_versio

    Outcome measures of chronic arthritis in Hong Kong: comparison of the AIMS2 (Chinese) and WHO quality of life - brief form (WHOQOL-BREF) (HK)

    Get PDF
    published_or_final_versio

    Improving Effective Surgical Delivery in Humanitarian Disasters: Lessons from Haiti

    Get PDF
    Kathryn Chu and colleagues describe the experiences of Médecins sans Frontières after the 2010 Haiti earthquake, and discuss how to improve delivery of surgery in humanitarian disasters

    Is ultrasonography-guided modified coaxial core biopsy of the breast a better technique?

    Get PDF
    Objective: To compare the diagnostic rate, patient comfort, and complications of ultrasonography-guided breast biopsy using a modified coaxial technique with ultrasonography-guided fine needle aspiration and traditional core biopsy. A secondary objective was to describe the use of the coaxial technique for the biopsy of breast lesions and our initial experience. Design: Retrospective study. Setting: A regional hospital in Hong Kong. Patients: Patients, who were referred for ultrasonography-guided fine needle aspiration or biopsy from 23 November 2007 to 19 March 2008, were divided into three groups. For breast lesions of 8 mm or smaller, fine needle aspirations were performed. For breast lesions larger than 8 mm, the patients were randomly divided into groups receiving traditional core biopsies and coaxial biopsies. The pathological reports were reviewed. Main outcome measures: Diagnostic rate, patient comfort assessed in terms of pain, and any procedural complications. Results: A total of 45 ultrasonography-guided fine needle aspirations or biopsies of breast lesions were performed. All core biopsies using the traditional core technique (n=15) and coaxial technique (n=16) were diagnostic. While for fine needle aspirations, three (21%) of 14 were not diagnostic and repeat biopsies were undertaken for the corresponding patients. Except for one breast lesion biopsied with the coaxial technique that revealed invasive ductal carcinoma, all others yielded benign lesions. The average pain score for coaxial biopsies was 2.2, while for traditional core biopsies and fine needle aspirations, average scores were 3.7 and 3.8, respectively (P=0.022). No procedure-related complication was documented with either of the three techniques. Conclusion: Modified coaxial core biopsy of the breast has an optimal diagnostic rate and hence avoids the need for repeat biopsies. It is associated with better patient comfort and no increase in the risk of complications.published_or_final_versio

    First Simultaneous Lidar Observations of Thermosphere‐Ionosphere Fe and Na (TIFe and TINa) Layers at McMurdo (77.84°S, 166.67°E), Antarctica With Concurrent Measurements of Aurora Activity, Enhanced Ionization Layers, and Converging Electric Field

    Get PDF
    We report the first simultaneous, common‐volume lidar observations of thermosphere‐ionosphere Fe (TIFe) and Na (TINa) layers in Antarctica. We also report the observational discovery of nearly one‐to‐one correspondence between TIFe and aurora activity, enhanced ionization layers, and converging electric fields. Distinctive TIFe layers have a peak density of ~384 cm−3 and the TIFe mixing ratio peaks around 123 km, ~5 times the mesospheric layer maximum. All evidence shows that Fe+ ion‐neutralization is the major formation mechanism of TIFe layers. The TINa mixing ratio often exhibits a broad peak at TIFe altitudes, providing evidence for in situ production via Na+ neutralization. However, the tenuous TINa layers persist long beyond TIFe disappearance and reveal gravity wave perturbations, suggesting a dynamic background of neutral Na, but not Fe, above 110 km. The striking differences between distinct TIFe and diffuse TINa suggest differential transport between Fe and Na, possibly due to mass separation

    Measurements of the vertical fluxes of atomic Fe and Na at the mesopause: implications for the velocity of cosmic dust entering the atmosphere

    Get PDF
    The downward fluxes of Fe and Na, measured near the mesopause with the University of Colorado lidars near Boulder, and a chemical ablation model developed at the University of Leeds, are used to constrain the velocity/mass distribution of the meteoroids entering the atmosphere and to derive an improved estimate for the global influx of cosmic dust. We find that the particles responsible for injecting a large fraction of the ablated material into the Earth's upper atmosphere enter at relatively slow speeds and originate primarily from the Jupiter Family of Comets. The global mean Na influx is 17,200 ± 2800 atoms/cm2/s, which equals 298 ± 47 kg/d for the global input of Na vapor and 150 ± 38 t/d for the global influx of cosmic dust. The global mean Fe influx is 102,000 ± 18,000 atoms/cm2/s, which equals 4.29 ± 0.75 t/d for the global input of Fe vapor

    Boundary Conditions for Interacting Membranes

    Get PDF
    We investigate supersymmetric boundary conditions in both the Bagger-Lambert and the ABJM theories of interacting membranes. We find boundary conditions associated to the fivebrane, the ninebrane and the M-theory wave. For the ABJM theory we are able to understand the enhancement of supersymmetry to produce the (4,4) supersymmetry of the self-dual string. We also include supersymmetric boundary conditions on the gauge fields that cancel the classical gauge anomaly of the Chern-Simons terms.Comment: 36 pages, latex, v2 minor typos correcte

    Security Analysis of Sensor Networks

    Get PDF
    Wireless sensor networks distribute a common sensing and computing task within the large number of participants that use wireless communication. Such networks require a self-organizing and energy-aware set of protocols. Several protocols have beed designed for such environments, however to make certain proof of their secureness, their formal analysis is required. In our article, we show an analysis framework capable of proving security properties of such protocols. Our methodology is based on the CSP process algebra. We will demonstrate its power by giving an attack possibility for an existing protocol, and the extensibility of the model will also be pointed
    corecore