164 research outputs found

    Temperature‐dependent orientation of diamond films on titanium and structural evolution of interfacial layers

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    X-ray diffraction analytical techniques have been used to investigate the influence of the deposition temperature (650–850 °C) on the composition and microstructure of the transition layers formed at the interface between titanium substrates and diamond thin films. The diamond coatings were produced by hot-filament chemical vapor deposition using a 1% methane/hydrogen mixture. X-ray diffraction analysis, performed both through θ–2θ scans and at grazing incidence, allowed investigation of the crystallographic properties and of the structural evolution of the various phases (TiC, TiH2, α-Ti) generated inside the intermediate reaction layers. The temperature-dependent orientation of diamond crystallites is discussed with reference to the complex structure of these interfacial layers

    Direct structural and mechanistic insights into fast bimolecular chemical reactions in solution through a coupled XAS/UV-Vis multivariate statistical analysis

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    In this work, we obtain detailed mechanistic and structural information on bimolecular chemical reactions occurring in solution on the second to millisecond time scales through the combination of a statistical, multivariate and theoretical analysis of time-resolved coupled X-ray Absorption Spectroscopy (XAS) and UV-Vis data. We apply this innovative method to investigate the sulfoxidation of p-cyanothioanisole and p-methoxythioanisole by the nonheme FeIV oxo complex [N4Py·FeIV(O)]2+ (N4Py = N,N-bis(2-pyridylmethyl)-N-bis(2-pyridyl)methylamine) in acetonitrile at room temperature. By employing statistical and multivariate techniques we determine the number of key chemical species involved along the reaction paths and derive spectral and concentration profiles for the reaction intermediates. From the quantitative analysis of the XAS spectra we obtain accurate structural information for all reaction intermediates and provide the first structural characterization in solution of complex [N4Py·FeIII(OH)]2+. The employed strategy is promising for the spectroscopic characterization of transient species formed in redox reactions. © The Royal Society of Chemistry

    Activation of C-H bonds by a nonheme iron(iv)-oxo complex: mechanistic evidence through a coupled EDXAS/UV-Vis multivariate analysis

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    The understanding of reactive processes involving organic substrates is crucial to chemical knowledge and requires multidisciplinary efforts for its advancement. Herein, we apply a combined multivariate, statistical and theoretical analysis of coupled time-resolved X-ray absorption (XAS)/UV-Vis data to obtain detailed mechanistic information for on the C-H bond activation of 9,10-dihydroanthracene (DHA) and diphenylmethane (Ph2CH2) by the nonheme FeIV-oxo complex [N4Py·FeIV(O)]2+ (N4Py = N,N-bis(2-pyridylmethyl)-N-bis(2-pyridyl)methylamine) in CH3CN at room temperature. Within this approach, we determine the number of key chemical species present in the reaction mixtures and derive spectral and concentration profiles for the reaction intermediates. From the quantitative analysis of the XAS spectra the transient intermediate species are structurally determined. As a result, it is suggested that, while DHA is oxidized by [N4Py·FeIV(O)]2+ with a hydrogen atom transfer-electron transfer (HAT-ET) mechanism, Ph2CH2 is oxidized by the nonheme iron-oxo complex through a HAT-radical dissociation pathway. In the latter process, we prove that the intermediate FeIII complex [N4Py·FeIII(OH)]2+ is not able to oxidize the diphenylmethyl radical and we provide its structural characterization in solution. The employed combined experimental and theoretical strategy is promising for the spectroscopic characterization of transient intermediates as well as for the mechanistic investigation of redox chemical transformations on the second to millisecond time scales. This journal i

    Multi-disciplinary Consensus Statement Document Vaccinal prevention in adult patients with diabetes mellitus

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    open8noopenIcardi G.; Francia F.; Di Bartolo P.; Mannino D.; Alti E.; Purrello F.; Sesti G.; Sessa A.Icardi, G.; Francia, F.; Di Bartolo, P.; Mannino, D.; Alti, E.; Purrello, F.; Sesti, G.; Sessa, A

    Prevalence and time course of post-stroke pain: A multicenter prospective hospital-based study

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    OBJECTIVE: Pain prevalence data for patients at various stages after stroke. DESIGN: Repeated cross-sectional, observational epidemiological study. SETTING: Hospital-based multicenter study. SUBJECTS: Four hundred forty-three prospectively enrolled stroke survivors. METHODS: All patients underwent bedside clinical examination. The different types of post-stroke pain (central post-stroke pain, musculoskeletal pains, shoulder pain, spasticity-related pain, and headache) were diagnosed with widely accepted criteria during the acute, subacute, and chronic stroke stages. Differences among the three stages were analyzed with χ(2)-tests. RESULTS: The mean overall prevalence of pain was 29.56% (14.06% in the acute, 42.73% in the subacute, and 31.90% in the chronic post-stroke stage). Time course differed significantly according to the various pain types (P < 0.001). The prevalence of musculoskeletal and shoulder pain was higher in the subacute and chronic than in the acute stages after stroke; the prevalence of spasticity-related pain peaked in the chronic stage. Conversely, headache manifested in the acute post-stroke stage. The prevalence of central post-stroke pain was higher in the subacute and chronic than in the acute post-stroke stage. Fewer than 25% of the patients with central post-stroke pain received drug treatment. CONCLUSIONS: Pain after stroke is more frequent in the subacute and chronic phase than in the acute phase, but it is still largely undertreated

    Critical Pathways for continuous quality improvement: a multicentric analysis on the management of patients with lung cancer in Italian best performing hospitals

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    Introduction: Critical pathways (CPs) are effective change management tools used to improve quality in healthcare nationally implemented in Italy in 2015. This study aims to map the country’s state-of-the-art regarding the adoption of CPs and to verify the existence of factors that determine the success of their implementation and the relative entity of their impact, by analysing the management of Lung Cancer (LC) as a case-study. Methods: Our methodology followed the SQUIRE guidelines for quality improvement reporting (2015). Starting from the 2017 ranking table published by the National Outcome Program, we selected and included in our sample all Italian hospitals who, according to Ministerial Decree n. 70/2015, met national quality threshold  for LC treatment. To investigate regional-level and hospital-level factors believed to be responsible for the successful implementation of a CP, a Google Modules questionnaire was constructed and sent to the selected facilities; subsequently, a web-based research was carried out for missing data.  Associations between variables were tested in STATA by means of correlation tests and a linear regression model.  Results: 41 hospitals matched our inclusion criteria. Of these, 68% defined an internal Lung Cancer Critical Pathway (LCCP). Our results confirmed the presence of critical success factors that favour the correct implementation of a LCCP. Conclusions: Notwithstanding the availability of CPs, their adoption in routine clinical practice still lacks consistency, suggesting the necessity to resort to digital solutions, to increment the level of regional commitment and workforce commitment and to reinforce quality standards monitoring

    A Novel Modeling for Assessing Frequency Behavior During a Hydro-to-Thermal Plant Black Start Restoration Test

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    Northern electric grid of Italy was involved in a black start mock drill. This test took place on November 2016 in order to check the coordination and efficiency of all the operational staffs and the automatic regulators involved in the case of a real blackout scenario. This paper presents the results of a research carried out in collaboration with Terna Rete Italia (the Italian Transmission System Operator), in order to find strengths and weaknesses and eventually to upgrade the existing restoration plan. Starting from the measures coming from generating plants and substations bars, the model of frequency regulation system for both the participating hydro and thermal power plants is developed. This work gives the system operator an essential tool to understand many complex dynamics and phenomena occurred during the test. At the same time, a robust model simulating the system behavior with different grid configurations is presented: it gives the opportunity to enhance both the classical power system control theory and the black start practices

    Quantitation of regional ejection fractions using gated tomographic imaging with Tc-99m-sestamibi

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    BACKGROUND: A new oro-dispersible film (ODF) formulation of sildenafil has been developed for the treatment of erectile dysfunction (ED) to overcome the drawbacks that some patients experience when taking the conventional film-coated tablet (FCT). AIM: To assess the effectiveness and safety of sildenafil ODF formulation in patients with ED who were using the conventional FCT. METHODS: From May 2017 through July 2017, 139 patients with ED were enrolled. Data from penile color-duplex ultrasound, medical history, hormonal evaluation, and patient self-administered questionnaires were collected. All patients were administered sildenafil 100-mg FCT for 4 weeks. Thereafter, they underwent a 2-week washout period and subsequently took sildenafil 75-mg ODF for 4 weeks. OUTCOMES: The International Index of Erectile Function (IIEF-15), Hospital Anxiety and Depression Scale (HADS), Patient Global Impressions of Improvement (PGI-I), and Clinician Global Impressions of Improvement (CGI-I) questionnaires were administered and severity of ED was classified as severe (IIEF-15 score ≤ 10), moderate (IIEF-15 score 11-16), or mild (IIEF-15 score = 17-25). RESULTS: All patients completed the final protocol. Differences in mean IIEF scores for erectile function, orgasmic function, sexual desire, and intercourse satisfaction were significantly in favor of sildenafil 100-mg FCT, whereas the mean score for overall satisfaction was in favor of sildenafil 75-mg ODF. A significant difference in changes in HADS score was found from washout to final follow-up (mean difference = -0.19; P < .01). For the ODF formulation, the median CGI-I score was 3.5 (interquartile range [IQR] = 2.5-4.5) and the median PGI-I score was 3.0 (IQR = 2.0-4.0). The median action time was 20.0 minutes (IQR = 15.0-30.0) and the median mouth time was 60.0 seconds (IQR = 30.0-120.0). CLINICAL IMPLICATIONS: The ODF formulation of a widely known drug, with the same safety and effectiveness of the FCT, was better appreciated by patients in overall satisfaction. STRENGTHS AND LIMITATIONS: This is the first clinical trial to assess the efficacy of a new formulation of sildenafil in patients with ED. The limitations of the study are related to the methodology used: it was not a case-control study and the patients were not drug-naïve for ED treatment. Therefore, only the "additional" side effects of the ODF formulation compared with FCT are reported. CONCLUSION: The new ODF formulation is as efficient and safe as the FCT formulation and offers a new choice of treatment to specialists for more precisely tailored therapy. Cocci A, Capece M, Cito G, et al. Effectiveness and Safety of Oro-Dispersible Sildenafil in a New Film Formulation for the Treatment of Erectile Dysfunction: Comparison Between Sildenafil 100-mg Film-Coated Tablet and 75-mg Oro-Dispersible Film. J Sex Med 2017;X:XXX-XXX
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