Physical and photocatalytic properties of sprayed Dy doped ZnO thin films under sunlight irradiation for degrading methylene blue.

Dysprosium-doped zinc oxide (ZnO) thin films have been prepared through spray pyrolysis onto glass substrates. Cross-sections of the deposited thin films were assessed through Scanning Electron Microscopy (SEM), showing thicknesses between 200 and 300 nm. The thin film roughness was evaluated using the obtained images from the Atomic Force Microscope (AFM) micrographs. The crystallographic structure of the samples was analyzed by X-ray diffraction (XRD) revealing polycrystalline thin films. However, the slight shift towards a higher 2θ angle in Dy-doped ZnO films as compared to the pure ones indicates the incorporation of Dy3+ into the ZnO crystal lattice. The analysis of the oxidation state via X-ray photoelectron spectroscopy (XPS) confirms the incorporation of Dy ions in the ZnO matrix. Besides, UV-Vis-NIR spectrophotometry analysis and photoluminescence (PL) spectroscopy showed that bandgap energy values of ZnO decreased when dysprosium doping increased. Therefore, Dy doped ZnO thin films can be potentially used as a solar-light-driven photocatalyst. Among the different doping yields, the ZnO doped with 6% dysprosium provides the highest degradation rate for methylene blue (MB) under solar irradiation. Specifically, 9% of dye degradation was achieved under sunlight irradiation for 120 minutes.

[Recurrent toxoplasmic retinochoroiditis after clindamycin treatment]. / Récurrence de la rétinochoroïdite toxoplasmique après traitement par clindamycine.

PURPOSE: To evaluate the efficacy and safety of subconjunctival injections of clindamycin associated with oral corticotherapy in the treatment of toxoplasmic retinochoroiditis (TRC) and its effect on recurrence. PATIENTS AND METHODS: This study investigated 21 patients (10 males and 11 females) who presented to an ophthalmological department from 1995 to 2000, aged 14-55 years (mean, 28 years), with unilateral TRC. They were treated with subconjunctival injections of clindamycin and systemic corticotherapy at a dose of 1 mg/kg/day. Clinical follow-up consisted of assessment of visual acuity and biomicroscopic fundus examination, completed by retinal angiography if necessary. RESULTS: We observed clinical improvement in 68.75% of patients within 4 days and in all patients healing of the chorioretinal area within 1.6 months. During the follow-up period ranging from 6 to 52 months (mean, 22 months), there have been two recurrences (9%) over the first 18 months. Tolerance of the injections was good. Serious side effects were noted in two patients: one case of conjunctival necrosis and one case of corneal and conjunctival erosion. CONCLUSION: In treating ocular toxoplasmosis, clindamycin appears to be a safe and effective substitute for the classic protocol (pyrimethamine-sulfadiazine, pyrimethamine-azithromycin), for which a 50% recurrence rate has been reported. It provides relatively good protection against recurrence and warrants testing in further controlled studies.

[Contusive retinal detachment: a retrospective review of 48 patients]. / Les décollements de rétine post contusifs.

PURPOSE: Analysis of the epidemiological, clinical and therapeutic characteristics of retinal detachment after ocular blunt trauma. MATERIAL AND METHODS: We retrospectively reviewed 48 patients with isolated retinal detachment after ocular blunt trauma, studying their epidemiological characteristics (age, sex and trauma circumstances), their clinic details and the surgical techniques used. RESULTS: The average age of our patients was 39.3 Years; most were male (75%). Assault and home accidents were the most common cause of ocular trauma (83.2%). Total retinal detachment was noted in 47.9%. Of the retinal breaks found, dialysis at the ora serrata was observed in 22%, atrophic holes in 33.9%, retinal breaks in 40.6% and giant tears in 4.2%. Most of the breaks were situated at the lower temporal quadrant. Forty one out of the 48 patients were operated on, with surgical treatment consisting in episcleral surgery in 38 cases and vitreoretinal surgery in three cases. Complete anatomical success was achieved in 92.7%. CONCLUSION: This survey shows that the prognosis of retinal detachment after ocular blunt trauma remains favorable given the young age and the absence of advanced vitreoretinal proliferation, but this should not affect the importance of prevention.

[Human basophil degranulation test and double diffusion in pulmonary hydatidosis]. / Test de dégranulation des basophiles humains et double diffusion dans l'hydatidose pulmonaire.

A slide human basophil degranulation test (HBDT) and a double-diffusion test were done in 37 patients with suspected pulmonary hydatid disease. Among the 31 patients in whom a diagnosis was firmly established, 22 had a pulmonary hydatid cyst and 9 did not (controls). The HBDT was at least 35% in 17 of the 22 patients with hydatid disease; 16 of these exhibited a precipitation arc. Among the 9 controls, none had a HBDT above 30% and three had a precipitation arc. In this localization of hydatid disease, compared to the double-diffusion technique, the HBDT has similar sensitivity (0.77 versus 0.73 but higher specificity (1 versus 0.67).