1,720,998 research outputs found

    A Frequency-Domain Linearized Euler Model for Turbomachinery Noise Radiation Through Engine Exhaust

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    A numerical model for the exhaust noise radiation problem is presented. In the model, it is assumed that an incoming wave is propagating through the exhaust nozzle, or the fan duct, and radiating outside. The near-field propagation is based on the solution of the linearized Euler equations in the frequency domain: for each wave number, a linearized Euler problem is solved using a finite element method on unstructured grids for arbitrarily shaped axisymmetric geometries. The frequency-domain approach enables the suppression of the Kelvin-Helmholtz instability waves. Moreover, each single calculation, limited to a single frequency, is well suited to the exhaust noise radiation problem in which the incoming wave can be treated as a superposition of elementary duct modes. To reduce the memory requirements, a continuous Galerkin formulation with linear triangular and quadrangular elements is employed and the global matrix inversion is performed with a direct solver based on a parallel memory distributed multifrontal algorithm for sparse matrices. The acoustic near field is then radiated in the far field using the formulation of Ffowcs Williams and Hawkings. Numerical calculations for a validation test case, the Munt problem, and two turbomachinery configurations are compared with analytical solutions and experimental dat

    Clobetasol propionate foam 0.05% as a novel topical formulation for plaque-type and scalp psoriasis

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    Objectives: To establish the efficacy of clobetasol propionate foam 0.05% in patients with plaque-type psoriasis and scalp psoriasis. Methods: We conducted an open-label study on 24 patients. Twelve patients affected by plaque-type psoriasis (group 1) and 12 patients with scalp psoriasis (group 2) applied clobetasol propionate foam 0.05% twice daily for 4 weeks. Results: Clobetasol propionate foam 0.05% led to a reduction of the disease severity. After 2 weeks the PASI score decreased from 7.5 at baseline to 2.5 (range: 0.8-4.6, SD: 1.1) in group 1 and from 5.7 to 1.7 (range: 0.2-4.8, SD: 1.1) in group 2. At week 4, the mean PASI was 2 (range: 0.6-4, SD: 1) and 1.1 (range: 0.2-2.2, SD: 0.6) in groups 1 and 2, respectively. In particular, at week 2, 83.3% of patients with plaque psoriasis and 75% with scalp psoriasis achieved an improvement of the PASI score from baseline >= 50% (PASI-50). At week 4, 91.6% of patients from group 1 and 100% from group 2 achieved or maintained PASI-50, while 41.6% in group 1 and 58.3% in group 2 demonstrated a further improvement, reaching PASI-75. Conclusion: The rapidity of effect and the good safety profile suggest a role for clobetasol propionate foam 0.05% in the management of both plaque-type and scalp psoriasis

    Un nuovo approccio fototerapico alle dermatosi croniche

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    308-nm excimer light has been shown to be safe and effective in the treatment of a variety of chronic skin diseases. Objectives of this study were to analyse the efficacy of MEL in vitiligo, mycosis fungoides and alopecia areata, and to examine the potential new indication of genital lichen sclerosus, prurigo, nodularis, localized scleroderma and granuloma annulare. 71 patients with common and persistent skin diseases were enrolled in this study: 32 with vitiligo (generalized and acro-facial type); 11 with prurigo nodularis; 9 with mycosis fungoides (MF) stage Ia, 8 with alopecia (2 universalis and 6 areata), 5 with localized scleroderma, 5 with genital lichen sclerosus, and 3 with granuloma annulare. The 308-nm excimer monochromatic non-coherent light was used at a fluence rate of 48 mW/ cm2 with a maximum irradiation area of 512 cm2 at 15 cm from the skin. Starting MED was based on a predetermined MED and subsequent doses according to clinical appearance and treatment response. An average of 12 sessions (from 6 to 18) was performed once weekly (range total dose 4-12.5J/cm2). Clinical response was evaluated using photographs, biopsies and specific clinical score. Follow-up was 6 and 12 months in psoriasis, 12 months in mycosis fungoides and 4 months for all other conditions. We observed complete remission in all patients affected by mycosis fungoides, excellent repigmentation in one third of vitiligo patients, hair re-growth in 3 patients with alopecia areata, an overall improvement in prurigo nodularis, a partial remission in patients affected by localised scleroderma, a complete remission in most patients with genital lichen sclerosus and granuloma annulare. We therefore confirm the use of MEL as a valid choice for the treatment of vitiligo and MF and we report for the first time that MEL produces a therapeutic response in prurigo nodularis, localised scleroderma, genital lichen sclerosus and granuloma annulare. These findings represent an important advance in their treatment suggesting MEL as a valid and new therapeutic optio

    Different monochromatic excimer light (308nm) in chronic skin diseases

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    Background: Ultraviolet radiation has been used for curative purposes in dermatologic conditions, especially in the last 30 years. Objectives: We analyzed the efficacy of monochromatic excimer light in psoriasis, palmoplantar pustulosis, vitiligo, mycosis fungoides and alopecia areata, and to examine potential new indications. Methods: Two hundred seventy-nine patients with common and persistent skin diseases were enrolled in an open prospective study: 152 patients with stable and localized plaque psoriasis, 47 with palmoplantar psoriasis, 7 with palmoplantar pustulosis, 32 with vitiligo, 11 with prurigo nodularis, 9 with mycosis fungoides stage Ia, 8 with alopecia, 5 with localized scleroderma, 5 with genital lichen sclerosus, and 3 with granuloma annulare. The 308 nm excimer light was used at a power density of 48 mW/cm(2). An average of 12 sessions (range, 6-18), one session per week, was performed and yielded a total dose range of 4-12.5 J/cm(2). Clinical response was assessed using photos, biopsies, and specific clinical scores. Patients were monitorized for 6 and 12 months for psoriasis, 12 months for mycosis fungoides, and 4 months for the remaining conditions. Results: We observed complete remission in more than 50% of patients with plaque psoriasis and palmoplantar dermatoses, respectively, complete remission in all patients affected by mycosis fungoides, excellent repigmentation in one third of vitiligo patients, hair regrowth in three patients with alopecia areata, an overall improvement in prurigo nodularis, a partial remission in patients affected by localized scleroderma, and a complete remission in most of the patients with genital lichen sclerosus and granuloma annulare. Conclusions: Our study confirms the use of monochromatic excimer light as a valid choice for the treatment of psoriasis, vitiligo, and mycosis fungoides; we also observed and report for the first time that monochromatic excimer light produces a therapeutic response in prurigo nodularis, localized scleroderma, genital lichen sclerosus, and granuloma annular

    Clobetasol propionate foam 0.05% as a novel topical formulation for plaque-type and scalp psoriasis

    No full text
    Objectives: To establish the efficacy of clobetasol propionate foam 0.05% in patients with plaque-type psoriasis and scalp psoriasis. Methods: We conducted an open-label study on 24 patients. Twelve patients affected by plaque-type psoriasis (group 1) and 12 patients with scalp psoriasis (group 2) applied clobetasol propionate foam 0.05% twice daily for 4 weeks. Results: Clobetasol propionate foam 0.05% led to a reduction of the disease severity. After 2 weeks the PASI score decreased from 7.5 at baseline to 2.5 (range: 0.8-4.6, SD: 1.1) in group 1 and from 5.7 to 1.7 (range: 0.2-4.8, SD: 1.1) in group 2. At week 4, the mean PASI was 2 (range: 0.6-4, SD: 1) and 1.1 (range: 0.2-2.2, SD: 0.6) in groups 1 and 2, respectively. In particular, at week 2, 83.3% of patients with plaque psoriasis and 75% with scalp psoriasis achieved an improvement of the PASI score from baseline >= 50% (PASI-50). At week 4, 91.6% of patients from group 1 and 100% from group 2 achieved or maintained PASI-50, while 41.6% in group 1 and 58.3% in group 2 demonstrated a further improvement, reaching PASI-75. Conclusion: The rapidity of effect and the good safety profile suggest a role for clobetasol propionate foam 0.05% in the management of both plaque-type and scalp psoriasis

    Vitiligo treatment with monochromatic excimer light and tacrolimus: results of an open randomized controlled study

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    Background data: Narrow band ultraviolet B (UVB) is an effective and safe option for the treatment of vitiligo. However, a complete and long-lasting repigmention of vitiligo patches is difficult to achieve. Combined treatments with novel sources of phototherapy and topical agents represent possible new strategies. Objective: The purpose of this study was to compare the efficacy of combined tacrolimus and 308-nm excimer light (MEL) vs 308-nm MEL monotherapy in treating vitiligo in a controlled study. Methods: Fifty-three patients affected by vitiligo were enrolled in this open prospective study. Patients were divided into three groups: Group I included 20 patients treated with MEL 308 nm twice weekly and oral vitamin E; Group II included 20 patients treated with MEL 308 nm twice weekly combined with 0.1% tacrolimus once a day and oral vitamin E; and Group III included 13 patients treated only with oral vitamin E. Efficacy was assessed at the end of 12 weeks based on the percentage of repigmentation. Results: Fifty-two patients completed 12 weeks of treatment. Group I (MEL + vitamin E) showed a moderate repigmentation in 35% of patients, good repigmentation in 30%, excellent repigmentation in 25%, and poor repigmentation in 10%; Group II (MEL + tacrolimus 0.1%+ vitamin E) presented moderate repigmentation in 25% of patients, good repigmentation in 40%, excellent repigmentation in 30%, and poor repigmentation in 5%; Group III (vitamin E) showed moderate repigmentation in 16% and 84% did not show signs of repigmentation. Conclusions: Our results demonstrate that the combination treatment of 0.1% tacrolimus ointment plus 308-nm MEL and 308-nm MEL monotherapy are effective, safe, and well tolerated for the treatment of vitiligo compared to treatment with vitamin E. Furthermore, this study suggests that an association with topical immunomodulators could enhance the clinical response in vitiligo, especially in more resistant anatomical site

    Monocromatic excimer Light treatment of psoriasis

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    B a c k g round: Various reports showed the efficacy of Narrow Band UVB (311-313 nm) and excimer laser (308 nm) in the treatment of psoriasis. Objective: To prove the efficacy of light produced by xenon-cloride excimer at 308 nm (Monochromatic Excimer Light, MEL) in the treatment of stable forms of localized plaque psoriasis. Patients and methods: This study was an open trial with 152 patients affected with stable mild to moderate plaque psoriasis (PASI score between 4 and 12) were t reated with a weekly session of MEL A total number of 6-16 sessions was p e rformed with a dose increase according to patient phototype and re s p o n s e . Results: 152 patients were enrolled in the study and 149 completed the pro t o c o l . Patients were followed up every two weeks, 57 patients for one-year and 92 patients for 6 months. After 4 months there was complete remission in 87 patients, partial remission in 37 and moderate improvement in 25 patients. Conclusions: These pre l i m i n a ry results suggest that MEL can be considered as a valid option for treatment of selected forms of localized plaque psoriasis
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