Highly separated transonic flows

Attention is given to the wind tunnel, to photographic visualization of the flow, and to measurements by pressure probes, hot wire anemometry and laser anemometry. The simultaneous use of different means of measurement provided a good description of the phenomenon, and indicated the existence of shocks and their stability, as well as the existence of the bubble, its dimensions, and in particular, the reattachment of its front. The results show that the bursting (or transition) of the bubble front is produced at an unstable position and creates a point of turbulent intensity which diffuses over the entire height of the flow

Early identification of learning problems in high risk preschool children

There has been increasing evidence that the early childhood years influence the later success of the child. Early identification of children with potential learning problems has received wide support from medical, psychological, and educational professionals as well as from parents. Researchers show that by the time the child fails in school much is already lost. It is important to recognize such high risk children in order to prevent possible failure

Anomalous Roughening of Viscous Fluid Fronts in Spontaneous Imbibition

We report experiments on spontaneous imbibition of a viscous fluid by a model porous medium in the absence of gravity. The average position of the interface satisfies Washburn's law. Scaling of the interface fluctuations provides a dynamic exponent z \simeq 3, indicative of global dynamics driven by capillary forces. The complete set of exponents clearly shows that interfaces are not self-affine, exhibiting distinct local and global scaling, both for time (b=0.64\pm 0.02, b* =0.33 \pm 0.03) and space (a=1.94 \pm 0.20, a_loc=0.94 \pm 0.10). These values are compatible with an intrinsic anomalous scaling scenario.Comment: 4 pages, 5 figure

A mixed methods study of perceived social support based on the medical outcomes study social support survey in adults with repeated challenges with HIV medication adherence

Numerous research studies in the HIV literature have documented social support as a key factor influencing adherence to antiretroviral therapy (ART). This is one of only a few studies to examine perceived social support among adults living with HIV who have had repeated challenges with medication adherence. A secondary analysis of quantitative and qualitative data from two intervention studies was conducted using a mixed methods design. Two overarching themes were associated with the lack of social support: extreme isolation and constant turmoil. Subthemes, included loneliness, structural vulnerability, and emotional distress. Overall social support was low in this vulnerable group, especially when compared to the general population and to adults living with other chronic health conditions. Strong correlations existed between all social support subscales of the Medical Outcomes Study Social Support Survey (MOS-SSS). The strongest positive correlation was found between affectionate support and positive social interaction (r = .870, p = less than .0001). These data suggest that participants who frequently self-reported a lack of persons to spend time with socially often lacked positive, supportive relationships in their lives. No significant variation was found between self-reported overall social support or subscale scores based on age or health variables. Convergent qualitative data excerpts corresponded with low quantitative social support scores in every dimension, confirming that adults living with HIV who repeatedly struggle with taking life-long HIV medications lack social support in many areas of their lives

Binary-mixture droplet evaporation: Lubrication approximation and coffee ring formation

This paper was presented at the 3rd Micro and Nano Flows Conference (MNF2011), which was held at the Makedonia Palace Hotel, Thessaloniki in Greece. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, Aristotle University of Thessaloniki, University of Thessaly, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute.In this paper the dynamics of an evaporating sessile droplet spreading on a horizontal substrate is reported. A mathematical model based on the lubrication approximation is developed accounting for Marangoni effect, contact line motion, and multi-component fluid. After validating the model through pure liquid spreading and evaporation, an extension of the model is performed on a binary component liquid in which composition changes occur during the drying process. Furthermore, the presence of particles in the fluid enables to retrieve the coffee-ring formation. A good qualitative and quantitative agreement between the model and experimental observations is found.This study is funded from ANR PAN’H 2008 CATIMINHY project