Shear and longitudinal viscosity of non-ionic C12E8 aqueous solutions

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

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

On the Use of Bayesian Artificial Intelligence for Hypothesis Generation in Psychiatry.

peer reviewedIn this study, I introduce the use of Bayesian Artificial Intelligence, namely through the probabilistic and structure learning of Bayesian Network models, for hypothesis generation in psychiatry. Bayesian Networks are directed acyclic graphical models that allow researchers to account for complexity in multivariate data sets, as well as identify what is the likely causal direction in detected associations. This in turns leads to more effective designs for confirmatory studies in clinical settings, that go beyond association studies and can provide meaningful impact in clinical practice. As an example, I use three different data sets to highlight several frameworks for hypothesis generation. Bayesian Networks are useful models since the early stages of knowledge generation in psychiatry, and they can be easily adopted by most applied and clinical researchers for use in quantitative studies

Investigation and Comparison of Networks of Psychopathic Traits in Psychiatric Inpatients and University Students.

peer reviewedThe Levenson Self-Report Psychopathy Scale (LSRPS) is a psychometric tool composed of 26 items to assess psychopathic traits. This study aims to perform a network analysis of this scale in a large sample composed of 100 hospitalized psychiatric patients and 256 French-speaking Belgian university students in medicine and to compare the network structure. We estimated a regularized partial correlation network for the 26 items of the questionnaire. Node predictability is used to assess the connectivity of items. The network comparison test (NCT) and statistical inference on sum scores are conducted to compare networks from the inpatients and the university students. The networks composed of LSRPS are mostly connected positively, but some negative interconnections were observed in both inpatients and university students, and node connectivity varies. Although the scores from inpatients are substantially higher than those of university students, network analysis didn't show any statistical difference in the overall connectedness. Network analysis is a valuable tool for exploring psychopathic traits and offers new insight into how they interact. In the network estimation, we concluded that the two domains of psychopathy are interrelated. This interconnectivity was observed in both subject groups. We hypothesize that such interconnectivity was present because environmental and genetic factors are intricately intertwined in the appearance of primary and secondary psychopathy. Meanwhile, although inpatients may have higher scores of psychopathic traits, those traits' connectedness isn't different from that of the general population. This finding aligns well with the theory of hysteresis in network analysis, which states that the connections among components of mental disorders do not disappear or reappear over time, but their importance may vary. Further studies may replicate our findings using different sample groups

The Borders of Mental Illness: Investigating Clusters of Diagnostic Criteria in Acute Presentations of Psychiatric Disorders.

peer reviewedThe impact of diagnostic delay in mental health is significant in terms of neurocognitive impairment, comorbidities, prognostic and socio-economical cost. For this reason, diagnostical research in psychiatry and the classification methods are continuously questioned. The network theory of mental disorders aims at contributing to the improvement of psychiatric diagnosis and considers mental disorders as the results of complex sets of interactions among symptoms instead of being their common cause. In this study, we use network theory and its associate statistical methods, namely Gaussian Graphical Models, centrality, and cluster analysis, to estimate respectively the interactions among symptoms from different disorders, their relative importance, and how they overlap, in a sample of psychiatric inpatients. The community detection found nine clusters with their interactions. Many are closely related to DSM criteria but some of them share symptoms from both diagnostics. One central symptom of the construct is Insomnia. There was a significant difference in the sum scores for psychotic symptoms, but not for bipolar symptoms, across psychotic and bipolar patients. This study needs however to be replicated in a bigger sample of different patients. Computing Bayesian Network to assess causalities in the network and adding other variables (such as biomarkers or therapeutic responses) could contribute to a more personalized diagnostic. How symptoms connect to each other in a specific time frame would define a person phenotype. Network analysis allows for investigating connections, identifying which symptoms are relatively important to the self-determination of disorders as well as how network nodes predict each other and arise in communities. For instance, in psychotic and mood disorders, sleep related symptoms or altered speech features and the importance of their communities in the probable transfer of symptomatology

Time-clustering of wave storms in the Mediterranean Sea

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.

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

Teen Dating Violence: A Mixed Methods Study in French-speaking Belgium.

peer reviewedBACKGROUND: "Teen dating violence" is a poorly studied issue in the literature. Several sociodemographic and psychiatric risk factors have been identified in the literature, and the consequences are numerous. The aim of this mixed study is to establish an initial inventory of the problem in French-speaking Belgium, to establish links with the socio-demographic and overall health characteristics of the population, and to issue recommendations for the future. SUBJECTS AND METHODS: A study by questionnaire was conducted among 103 young people aged between 14 and 18 living in French-speaking Belgium and speaking French in particular. Qualitative and quantitative (descriptive and inferential statistics) analyses were performed. RESULTS: 29.1% of respondents experienced violence. Significant links exist between the fact of having experienced violence and consumption as well as the presence of STDs. The combination of potential risk factors predicts a considerable part of the violence in the sample. A significant link exists between the fact of being subjected to violence and a high score on the scale of depression and violence suffered and committed. CONCLUSION: The prevalence of teen dating violence is relatively high in Belgium. A link between these and a large part of the potential consequences studied could be highlighted through the study

Italy. A country shaped by man

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