4,673 research outputs found

    Infrared-Improved Soft-wall AdS/QCD Model for Mesons

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    We construct and investigate an infrared-improved soft-wall AdS/QCD model for mesons. Both linear confinement and chiral symmetry breaking of low energy QCD are well characterized in such an infrared-improved soft-wall AdS/QCD model. The model enables us to obtain a more consistent numerical prediction for the mass spectra of resonance scalar, pseudoscalar, vector and axial-vector mesons. In particular, the predicted mass for the lightest ground state scalar meson shows a good agreement with the experimental data. The model also provides a remarkable check for the Gell-Mann-Oakes-Renner relation and a sensible result for the space-like pion form factor.Comment: 15 pages, 4 figures, 7 tables, published versio

    Far-Field Tunable Nano-focusing Based on Metallic Slits Surrounded with Nonlinear-Variant Widths and Linear-Variant Depths of Circular Dielectric Grating

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    In this work, we design a new tunable nanofocusing lens by the linear-variant depths and nonlinear-variant widths of circular grating for far field practical applications. The constructively interference of cylindrical surface plasmon launched by the subwavelength metallic structure can form a subdiffraction-limited focus, and the focal length of the this structures can be adjusted if the each groove depth and width of circular grating are arranged in traced profile. According to the numerical calculation, the range of focusing points shift is much more than other plasmonic lens, and the relative phase of emitting light scattered by surface plasmon coupling circular grating can be modulated by the nonlinear-variant width and linear-variant depth. The simulation result indicates that the different relative phase of emitting light lead to variant focal length. We firstly show a unique phenomenon for the linear-variant depths and nonlinear-variant widths of circular grating that the positive change and negative change of the depths and widths of grooves can result in different of variation trend between relative phases and focal lengths. These results paved the road for utilizing the plasmonic lens in high-density optical storage, nanolithography, superresolution optical microscopic imaging, optical trapping, and sensing.Comment: 14pages,9figure

    Comparison of Sterile and Clean Dressing Techniques in Post-operative Surgical Wound Infection in a Chinese Healthcare Facility

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    Purpose: To investigate the effect of sterile and clean dressing techniques on wound management in a Chinese hospital, and to compare their impact on wound healing and the cost of the dressing materials with respect to postoperative surgical wounds.Methods: A total of 130 patients, comprising 70 (53.8 %) males and 60 (46.2 %) females, who had undergone surgery in The Affiliated Hospital of Changchun Traditional Chinese Medicine University, Changchun, China in 2012 – 2014 were enrolled in the study. Of these, 65 (50 %) received sterile dressings and 65 (50 %) clean dressings. A control group comprising 25 patients, 15 (60 %) males and 10 (40 %) females, who attended the clinic for change dressings only, was also included. The patients’ dressings were changed four times daily with 2x sterile and 2x clean dressings. Details of all the changes, including the nutritional status of the patients, were recorded. The patients were followed-up up to the time of their discharge.Results: Twelve (18.5 %) patients out of those who received sterile or clean dressings were found to have acquired an infection. The size of the wounds was approximately 1.8 to 32.4 cm3 (mean: 5.2 ± 6.4 cm3) in size at the start of the study and 0.6 to 4.2 cm3 at the end of the study. A significant difference was identified between the sterile and clean dressing groups at the beginning of the study (U = 72.5; p < 0.12). A decrease in wound size was observed in both of these groups but was not statistically significant, while the change in wound volume, was significantly different (U = 84.5; p < 0.25). When the cost of the two dressing types was compared, the sterile items were more expensive than that of the clean items; thus, sterile dressing procedure was significantly more costly than clean dressing procedure (p < 0.01).Conclusion: With mounting concern regarding antimicrobial resistance and hospital-acquired infections, suitable wound dressing techniques are required to prevent infection and reduce the duration of wound healing after surgery without compromising patient safety.Keywords: Wound dressing, Postoperative, Antimicrobial resistance, Hospital acquired infection
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