535 research outputs found

    Electrocatalytic performance of PbO2 films in the degradation of dimethoate insecticide

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    This study was performed to find the best experimental conditions for the electrochemical removal of the insecticide dimethoate (C5H12NO3PS2) from aqueous solutions using a lead dioxide niobium anode. The process was studied under galvanostatic polarisation mode. The influence of applied current density (10–50 mA·cm–2), initial chemical oxygen demand COD0 (100–550 mg·ℓ–1), temperature (30–70°C) and pH (3–11) on COD and instantaneous current efficiency (ICE) was studied. The results showed that almost 90% of COD removal was achieved under optimal experimental conditions, indicating that electrochemical oxidation on a PbO2 anode is a suitable method for treatment of water polluted with dimethoate. It was found that the decay of COD generally followed a pseudo first-order kinetic and the oxidation rate was favoured by increasing the applied current density, temperature, pH and initial COD. The greatest COD removal (90%) was obtained when using an applied current density of 50 mA·cm–2, COD0 = 320 mg·ℓ–1, pH = 11, T = 70°C and electrolysis time = 8 h.Keywords: Electrochemical degradation; hydroxyl radicals; organic pollutants; lead dioxide; wastewate

    Physiological and Biochemical behaviours and antioxidant response of Helianthus annuus under Lanthanum and Cerium Stress

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    The continuous progress of global manufacturing and anthropogenic activities has resulted in excessive environmental metallic pollution, particularly with rare earth elements (REEs) which have become a prevalent issue of global concern due to their high toxicity and widespread existence. REEs-contaminated soils could ruin agriculture by inducing plant physiology disturbances in various crops that are considered the principal link of the human food chain. The main purpose of the present work is to assess the phytotoxicity of two light REEs, lanthanum (La) and cerium (Ce), in Helianthus annuus after 14 days of exposure to different concentrations of La and Ce (0, 1, 2.5, 5, and 10 µM). Plants showed different variations in shoot and root lengths at the end of the trial period. The accumulation of photosynthetic pigments, such as chlorophylls and carotenoids, as well as the photosynthetic efficiency, the non-photochemical quenching, the photosynthetically active radiation, and the electron transport rate, increased in the two REE treatments. Hydrogen peroxide significantly increased in all applied concentrations of La and Ce. A significant increase in malondialdehyde content was noticed only when plants were exposed to 2.5 µM La and 10 µM Ce. Results also demonstrated that La and Ce induced an increase in the activity of superoxide dismutase, peroxidase, and catalase (only the highest concentration of La decreased catalase activity). The exposure to different REE concentrations induced the accumulation of La and Ce in the plants, mainly in roots. Helianthus annuus showed an effective resistance behaviour facing La- and Ce-induced stresses

    Enhanced light trapping using plasmonic nanoparticles

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    International audiencePlasmonics is a new light trapping method used in photovoltaic (PV) solar cells. A significant enhancement of the scattered and absorbed incident light due to the use of silver nanoparticles (Ag-NPs) was observed, which yield to the exaltation of the electromagnetic field in the vicinity of these NPs. In this context, we investigate optically and morphologically the effect of the NPs size dependence on the localized surface plasmon resonance. Extinction, absorption and scattering cross sections are calculated using Mie theory

    057 A simple prediction score for significant renal artery stenosis in patients with coronary artery disease

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    BackgroundRenal artery stenosis (RAS) is a strong independent predictor of mortality in patients (pts) with coronary artery disease (CAD).Aim of studyTo develop and validate a score predicting RAS in patients with CAD.MethodsThree hundred consecutive pts (50 females) with significant CAD underwent abdominal aortography following coronary angiography to screen for significant RAS defined as luminal narrowing of > 50%. Univariate and multivariate analyses were performed comparing pts with and without RAS. Significant factors associated with RAS were included in constructing a score that predicts RAS.The score was internally validated in pts randomly selected from the entire study group (validation group; n=103), using ROC curves and the Hosmer-Lemeshow goodness-of-fit test.ResultsTwenty-seven pts (9%) had a significant RAS. Univariate predictors of significant RAS were: age > 65 years (OR=4.5, p < 0.0001), hypertension (OR=3.6, p=0.001), and female gender (OR=3.6, p=0.015). We found a tendency of more prevalent renal insufficiency (37.1% vs. 21.5%; p=0.05) and the presence of 2 or more significant CAD lesions (70.4% vs. 50.9%; p=0.05) in pts with RAS.Multivariate analysis showed that age > 65 years (OR=4.1%, 95% CI=1.6-10.3, p=0.003) and hypertension (OR=3.1, 95% CI=1.2-7.7, p=0.015) were independent predictors of RAS. The ranged from 0 to 7: 2 points for age > 65 years and hypertension 1 point for female gender, renal insufficiency, and > 3-vessel disease). Internal validation showed a good performance (ROC curve = 0.79 and Chi2 Lemeshow = 3.45). For a score < 2, the negative predictive value is 98%. Applying this criteria, 48.3% of our population would not require systematic abdominal angiography.ConclusionThe performance of our predictive score was good, and significant reduction in the need to perform systematic abdominal aortography could be expected with the use of this score

    La déhiscence du canal semi circulaire supérieur

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    Introduction : Superior semicircular canal dehiscence is a rare entity witch is recently described. The common symptom is pressure-induced vertigo.Patients and methods: we report 2 cases of superior semicircular canal dehiscence identified by computed tomography (CT) of the petrous bone in patients with mixed hearing loss and a normal tympanic membrane.Results: Superior semicircular canal dehiscence was bilateral in 1 patient.Mixed hearing loss with a normal tympanic membrane without vertigo was the presenting manifestation in all cases. Ultrahigh-resolution CT of the petrous bones with coronal and sagittal sections provided the diagnosis of superior semicircular canal dehiscence.Conclusion: Mixed hearing loss with a normal tympanic membrane should suggest superior semi circular canal dehiscence. Coronal and sagittal CT sections less than 1 mm in thickness establish the diagnosis.Key words : Superior semicircular canal, dehiscence, hearing loss

    Medical treatment or surgery for colorectal endometriosis? : results of a shared decision-making approach

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    STUDY QUESTION: What is the degree of patient satisfaction in women with symptomatic colorectal endometriosis who choose medical or surgical treatment after a shared decision-making (SDM) process? SUMMARY ANSWER: The degree of satisfaction with treatment was high both in women who chose medical treatment with a low-dose oral contraceptive (OCP) or a progestin, and in those who chose to undergo surgical resection of bowel endometriosis. WHAT IS KNOWN ALREADY: Hormonal therapies and surgery for colorectal endometriosis have been investigated in non-comparative studies with inconsistent results. STUDY DESIGN, SIZE, DURATION: Parallel cohort study conducted on 87 women referring to our centre with an indication to surgery for colorectal endometriosis. A standardised SDM process was adopted, allowing women to choose their preferred treatment. Median follow-up was 40 [18-60] months in the medical therapy group and 45 [30-67] in the surgery group. PARTICIPANTS/MATERIALS, SETTING, METHODS: Patients with endometriosis infiltrating the proximal rectum, the rectosigmoid junction, and the sigmoid, not causing severe sub-occlusive symptoms were enroled. A total of 50 patients chose treatment with an OCP (n = 12) or a progestin (n = 38), whereas 37 women confirmed their previous indication to surgery. Patient satisfaction was graded according to a 5-category scale. Variations in bowel and pain symptoms were measured by means of a 0-10 numeric rating scale. Constipation was assessed with the Knowles-Eccersley-Scott Symptom Questionnaire (KESS), health-related quality of life with the Short Form-12 questionnaire (SF-12), psychological status with the Hospital Anxiety and Depression scale (HADS) and sexual functioning with the Female Sexual Function Index (FSFI). MAIN RESULTS AND THE ROLE OF CHANCE: Six women in the medical therapy group requested surgery because of drug inefficacy (n = 3) or intolerance (n = 3). Seven major complications were observed in the surgery group (19%). At 12-month follow-up, 39 (78%) women in the medical therapy group were satisfied with their treatment, compared with 28 (76%) in the surgery group (adjusted odds ratio (OR), 1.37; 95% confidence interval (CI), 0.45-4.15; intention-to-treat analysis). Corresponding figures at final follow-up assessment were 72% in the former group and 65% in the latter one (adjusted OR, 1.74; 95% CI, 0.62-4.85). The 60-month cumulative proportion of dissatisfaction-free participants was 71% in the medical therapy group compared with 61% in the surgery group (P = 0.61); the Hazard incidence rate ratio was 1.21 (95% CI, 0.57-2.62). Intestinal complaints were ameliorated by both treatments. Significant between-group differences in favour of medical treatment were observed at 12-month follow-up in diarrhoea, dysmenorrhoea, non-menstrual pelvic pain and SF-12 physical component scores. The total HADS score improved significantly in both groups, whereas the total FSFI score improved only in women who chose medical therapy. LIMITATIONS REASONS FOR CAUTION: As treatments were not randomly assigned, selection bias and confounding are likely. The small sample size exposes to the risk of type II errors. WIDER IMPLICATIONS OF THE FINDINGS: When adequately informed and empowered through a SDM process, most patients with non-occlusive colorectal endometriosis who had already received a surgical indication, preferred medical therapy. The possibility of choosing the preferred treatment may allow maximisation of the potential effect of the interventions. STUDY FUNDING/COMPETING INTEREST(S): This study was financed by Italian fiscal contribution '5 7 1000'-Ministero dell'Istruzione, dell'Universit\ue0 e della Ricerca-devolved to Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Ca' Granda Ospedale Maggiore Policlinico, Milano, Italy. P.V., M.P.F., R.R., D.D., A.R., P.M., O.D.G. and M.C. declare that they have no conflicts of interest. E.S. received grants from Ferring and Serono

    Hematome organise du sinus maxillaire a propos d’un cas

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    L’hématome organisé du sinus maxillaire est une entité rare. Son étiopathogénie reste incertaine. Nous rapportons le cas d’une patiente âgée de 16 ans présentant une épistaxis unilatérale droite de grande abondance avec une endoscopie nasale strictement normale. L’imagerie était en faveur d’une tumeur vasculaire du sinus maxillaire. Une exérèse chirurgicale complète a été réalisée par voie combinée avec des suites simples. L’examen anatomopathologique a conclu à un hématome organisé du sinus maxillaire. Nous discutons, dans ce travail, l’étiopathogénie, les caractéristiques cliniques, radiologiques et les volets thérapeutiques de cette entité.Mots clés : Hématome organisé, sinus maxillaire, tomodensitométrie, chirurgie
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