161 research outputs found

    Shear and longitudinal viscosity of non-ionic C12E8 aqueous solutions

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    We present measurements of the steady shear viscosity, the longitudinal elastic modulus and the ultrasonic absorption in the one-phase isotropic liquid region of the nonionic surfactant C12E8 aqueous solutions. The overall results support the presence of two separated intervals of concentration corresponding to different structural properties. In the surfactant-rich region the temperature dependence of the steady shear viscosity follows an equation characteristic of glass-like systems. The ultrasonic absorption spectra show unambiguous evidence of viscoelastic behaviour described by a Cole-Cole relaxation formula. In the water-rich region the behaviour of the measured quantities are more complex and reflect the presence of dispersed aggregates whose size increases with temperature and concentration. An additional low frequency contribution is also observed, which is ascribed to the exchange of water molecules and/or surfactant monomers between the aggregates and the bulk solvent region.Comment: 23 Pages, 7 Figures, 1 Table, submitted to J. Phys. Chem B, accepted for publicatio

    A MACHINE LEARNING APPROACH TO RELATIONSHIPS AMONG ALEXITHYMIA COMPONENTS

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    Background: The aim of this paper is to explore the network structures of alexithymia components and compare results with relevant prior literature. Subjects and methods: In a large sample of university students, undirected and directed network structures of items from the Bermond Vorst Alexithymia Questionnaire form B are estimated with state-of-the-art network analysis and structure learning tools. Centrality estimates are used to address the topic of item redundancy and select relevant alexithymia components to study. Results: Alexithymia components present positive as well as negative connections; poor fantasy and emotional insight are identified as central items in the network. Conclusions: The undirected network structure of alexithymia components reports new features with respect to prior literature, and the directed network structures offers new insight on the construct

    Time-clustering of wave storms in the Mediterranean Sea

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    In this contribution we identify storm time-clustering in the Mediterranean Sea through a comprehensive analysis of the Allan Factor. This parameter is evaluated from long time series of wave height provided by oceanographic buoy measurements and hindcast re-analysis of the whole basin, spanning the period 1979-2014 and characterized by a horizontal resolution of about 0.1 degree in longitude and latitude and a temporal sampling of one hour (Mentaschi et al., 2015). The nature of the processes highlighted by the AF and the spatial distribution of the parameter are both investigated. Results reveal that the Allan Factor follows different curves at two distinct time scales. The range of time scales between 12 hrs to 50 days is characterised by a departure from the Poisson distribution. For timescales above 50 days, a cyclic Poisson process is identified. The spatial distribution of the Allan Factor reveals that the clustering at smaller time scales is present in the North-West of the Mediterranean, while seasonality is observed in the whole basin. This analysis is believed to be important to assess the local increased flood and coastal erosion risks due to storm clustering

    Effects of rocuronium bromide on globe position and respiratory function in isoflurane-anesthetized dogs: a comparison between three different dosages.

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    Objective To evaluate the effect on globe position and respiration of three dosages of intravenous rocuronium in isoflurane-anesthetized dogs. Animal studied Thirty-two dogs anesthetized for ophthalmic procedures. Procedures The dogs were divided into four groups, each of eight animals (G1-G4). G1, G2, G3 received 0.075, 0.05, 0.03 mg/kg of IV rocuronium, respectively; G4 received 0.9% NaCl IV; all the treatments were administered when an end-tidal isoflurane of 1.1–1.2% was reached. Anesthesia was obtained with dexmedetomidine (2.5 mcg/kg IV), methadone (0.1 mg/kg IV), propofol (2 mg/kg IV), and isoflurane in oxygen. Neuromuscular function was assessed with acceleromyography by stimulation of the peroneal nerve using the train-of-four (ToF) and the ToF ratio (ToFR). Monitoring of cardiovascular and respiratory functions was performed. Changes in globe position were recorded. Results All three dosages of rocuronium produced centralization of the globe. Duration was 24.3 ± 4.2, 23.4 ± 3.6, and 8.7 ± 2.8 min, for G1, G2, and G3, respectively. The control group did not show globe centralization. No significant differences were found among the four groups in cardiovascular and respiratory parameters. Minute volume and ToFR were significantly lower in G1 compared with baseline values. Conclusions All doses of rocuronium resulted in globe centralization. The higher dose provoked a transient respiratory depression and some degree of skeletal muscular blockade detectable with ToFR. No alterations in respiratory activity were present when 0.05 mg/kg was used. The 0.03 mg/kg dosage could be useful for very short ophthalmic procedures

    Italy. A country shaped by man

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    Catalogo, in inglese, del Programma "Italy. A country shaped by man" costituito da varie mostre, rassegne, incontri e una multivisione volta a promuovere l'immagine dell'Italia all'estero.- Why "Italy. A country shaped by man"? , Marcello Pacini #11- Italy through the camera's eye, Giovanni Chiaramonte #85- Another face of Italian art, Giuliano Briganti #11

    Cittadinanza attiva e Costituzione

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    Il percorso formativo si propone di fornire le conoscenze basilari del Diritto costituzionale in una prospettiva di maturazione negli studenti dei fondamenti culturali della cittadinanza attiva, che rappresenta una condizione indispensabile nel processo di sviluppo della persona e nell’ambito delle relazioni sociali, con particolare riguardo a quelle che interessano il contesto del lavoro. Il programma si articolerà in un primo incontro con il coordinatore scientifico Prof. Alberto Lucarelli di impostazione seminariale, in occasione del quale verranno illustrati i principi fondativi del modello di Stato democratico rappresentativo che sono sanciti nella nostra Carta costituzionale. A seguire, verranno realizzati dei moduli laboratoriali su specifici temi che verranno trattati sulla base di un più diretto coinvolgimento degli studenti, attraverso ad esempio simulazioni, realizzazione di mappe concettuali, etc

    Intraoperative use of tranexamic acid to reduce transfusion rate in patients undergoing radical retropubic prostatectomy: double blind, randomised, placebo controlled trial

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    Objectives To determine the efficacy of intraoperative treatment with low dose tranexamic acid in reducing the rate of perioperative transfusions in patients undergoing radical retropubic prostatectomy

    Understanding how individualised physiotherapy or advice altered different elements of disability for people with low back pain using network analysis.

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    Purpose The Oswestry Disability Index (ODI) is a common aggregate measure of disability for people with Low Back Pain (LBP). Scores on individual items and the relationship between items of the ODI may help understand the complexity of low back disorders and their response to treatment. In this study, we present a network analysis to explore how individualised physiotherapy or advice might influence individual items of the ODI, and the relationship between those items, at different time points for people with LBP. Methods Data from a randomised controlled trial (n = 300) comparing individualised physiotherapy versus advice for low back pain were used. A network analysis was performed at baseline, 5, 10, 26 and 52 weeks, with the 10 items of the Oswestry Disability Index modelled as continuous variables and treatment group (Individualised Physiotherapy or Advice) modelled as a dichotomous variable. A Mixed Graphical Model was used to estimate associations between variables in the network, while centrality indices (Strength, Closeness and Betweenness) were calculated to determine the importance of each variable. Results Individualised Physiotherapy was directly related to lower Sleep and Pain scores at all follow-up time points relative to advice, as well as a lower Standing score at 10-weeks, and higher Lifting and Travelling scores at 5-weeks. The strongest associations in the network were between Sitting and Travelling at weeks 5 and 26, between Walking and Standing at week 10, and between Sitting and Standing scores at week 52. ODI items with the highest centrality measures were consistently found to be Pain, Work and Social Life. Conclusion This study represents the first to understand how individualised physiotherapy or advice differentially altered disability in people with LBP. Individualised Physiotherapy directly reduced Pain and Sleep more effectively than advice, which in turn may have facilitated improvements in other disability items. Through their high centrality measures, Pain may be considered as a candidate therapeutic target for optimising LBP management, while Work and Socialising may need to be addressed via intermediary improvements in lifting, standing, walking, travelling or sleep. Slower (5-week follow-up) improvements in Lifting and Travelling as an intended element of the Individualised Physiotherapy approach did not negatively impact any longer-term outcomes. Trials registration ACTRN12609000834257
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