Learning from medical data streams: an introduction

Clinical practice and research are facing a new challenge created by the rapid growth of health information science and technology, and the complexity and volume of biomedical data. Machine learning from medical data streams is a recent area of research that aims to provide better knowledge extraction and evidence-based clinical decision support in scenarios where data are produced as a continuous flow. This year's edition of AIME, the Conference on Artificial Intelligence in Medicine, enabled the sound discussion of this area of research, mainly by the inclusion of a dedicated workshop. This paper is an introduction to LEMEDS, the Learning from Medical Data Streams workshop, which highlights the contributed papers, the invited talk and expert panel discussion, as well as related papers accepted to the main conference

A NOTE ON TRANSIENT HEAT TRANSFER PROBLEMS WITH TEMPERATURE-DEPENDENT THERMAL CONDUCTIVITY AND THERMAL DIFFUSIVITY

In this work it is presented a numerical procedure for solving transient heat transfer problems in which the thermal diffusivity is strongly dependent on the temperature, with the aid of the Kirchhoff transformation associated to an usual finite difference approach. The first step consists of eliminating the nonlinear terms associated to the derivatives with respect to the position, by means of a Kirchhoff transformation, giving rise to a partial differential equation with only one nonlinear term (involving the coefficient of the derivative with respect to the time). The advance in time is carried out assuming the thermal diffusivity evaluated at a known temperature, giving rise to a semi-implicit scheme. Comparisons between this approach and the usual hypothesis are carried out in order to illustrate the effect of the dependence between the temperature and the thermal diffusivity. Some typical results are presented, based on the (6H-SiC) Silicon Carbide properties

The effect of polydispersity on the ordering transition of adsorbed self-assembled rigid rods

Extensive Monte Carlo simulations were carried out to investigate the nature of the ordering transition of a model of adsorbed self-assembled rigid rods on the bonds of a square lattice [Tavares et. al., Phys. Rev E 79, 021505 (2009)]. The polydisperse rods undergo a continuous ordering transition that is found to be in the two-dimensional Ising universality class, as in models where the rods are monodisperse. This finding is in sharp contrast with the recent claim that equilibrium polydispersity changes the nature of the phase transition in this class of models [L`opez et. al., Phys. Rev E 80, 040105(R)(2009)].Comment: 19 pages, 5 figure

Properties of patchy colloidal particles close to a surface: a Monte Carlo and density functional study

We investigate the behavior of a patchy particle model close to a hard-wall via Monte Carlo simulation and density functional theory (DFT). Two DFT approaches, based on the homogeneous and inhomogeneous versions of Wertheim's first order perturbation theory for the association free energy are used. We evaluate, by simulation and theory, the equilibrium bulk phase diagram of the fluid and analyze the surface properties for two isochores, one of which is close to the liquid side of the gas-liquid coexistence curve. We find that the density profile near the wall crosses over from a typical high-temperature adsorption profile to a low-temperature desorption one, for the isochore close to coexistence. We relate this behavior to the properties of the bulk network liquid and find that the theoretical descriptions are reasonably accurate in this regime. At very low temperatures, however, an almost fully bonded network is formed, and the simulations reveal a second adsorption regime which is not captured by DFT. We trace this failure to the neglect of orientational correlations of the particles, which are found to exhibit surface induced orientational order in this regime

Perceptions of sexual abuse in sport: A qualitative study in the Portuguese sports community

Child sexual abuse is a complex issue that can take place in different contexts. Sports settings have specific features which pose increased risk for sexual abuse to occur. Recently, a country-specific roadmap for effective child safeguarding in sport was launched. Considering the need to achieve a comprehensive picture of violence against children in sports settings in Portugal, we analyzed the perceptions of the sports community in Portugal regarding child sexual abuse, its victims and perpetrators, and the specific risk factors in sports settings, as studies about this specific topic are scarce at the national level. A descriptive exploratory study was conducted using an online questionnaire with open-ended questions. Three hundred participants, i.e., sports managers, coaches, and athletes over 18 years of age (M = 33.13; SD = 13.062), of which 55.7% were female, answered. A thematic analysis of these data was conducted using NVivo software. Inter-rater agreement was strong for almost all variables. Results indicated that sexual abuse is perceived as being associated with physical and emotional abusive behaviors for which there is no consent from the victim, in a relationship that is guided by a relationship with power imbalances. Victims were mainly perceived as being female children, and perpetrators as adult males in a powerful position over the victim. As to possible signs of sexual abuse victimization, results showed that the participants identify behaviors, such as isolation, and physical evidence, such as marks and injuries. Risk factors specific to sports setting included the physical contact involved in many modalities, as well as the close and trustful relationship established between coach and athlete. Results are in line with previous studies showing that coaches, athletes, and sports managers share a common understanding of sexual abuse, although not always accurate. These results shed light on important practical and policy implications relevant to country-specific sport policies for effectively safeguarding children.info:eu-repo/semantics/publishedVersio

Why discouraged borrowers exist? An empirical (re)examination from less developed countries

Using the fourth-round database of the Business Environment and Enterprise Performance Survey (2008/09 BEEPS), this study examines the determinants of discouragement in less developed countries in Eastern Europe and Central Asia. The results show that whereas firms' opaqueness, demographic factors, and distance between lenders and borrowers better explain the discouragement due to tough loan prices and/or loan application procedures, firm risk and banking concentration explain the incidence of discouraged borrowers due to the fear of rationing. Innovator status, the legal protection of creditors and lenders in the event of default, and the coverage of information sharing instruments help explain discouragement in a transversal way.info:eu-repo/semantics/acceptedVersio

Diffusion-limited deposition of dipolar particles

Deposits of dipolar particles are investigated by means of extensive Monte Carlo simulations. We found that the effect of the interactions is described by an initial, non-universal, scaling regime characterized by orientationally ordered deposits. In the dipolar regime, the order and geometry of the clusters depend on the strength of the interactions and the magnetic properties are tunable by controlling the growth conditions. At later stages, the growth is dominated by thermal effects and the diffusion-limited universal regime obtains, at finite temperatures. At low temperatures the crossover size increases exponentially as T decreases and at T=0 only the dipolar regime is observed.Comment: 5 pages, 4 figure