A Semi-Markov Modulated Interest Rate Model

In this paper we propose a semi-Markov modulated model of interest rates. We assume that the switching process is a semi-Markov process with finite state space E and the modulated process is a diffusive process. We derive recursive equations for the higher order moments of the discount factor and we describe a Monte Carlo al- gorithm to execute simulations. The results are specialized to classical models as those by Vasicek, Hull and White and CIR with a semi-Markov modulation

Interactive Robot Learning of Gestures, Language and Affordances

A growing field in robotics and Artificial Intelligence (AI) research is human-robot collaboration, whose target is to enable effective teamwork between humans and robots. However, in many situations human teams are still superior to human-robot teams, primarily because human teams can easily agree on a common goal with language, and the individual members observe each other effectively, leveraging their shared motor repertoire and sensorimotor resources. This paper shows that for cognitive robots it is possible, and indeed fruitful, to combine knowledge acquired from interacting with elements of the environment (affordance exploration) with the probabilistic observation of another agent's actions. We propose a model that unites (i) learning robot affordances and word descriptions with (ii) statistical recognition of human gestures with vision sensors. We discuss theoretical motivations, possible implementations, and we show initial results which highlight that, after having acquired knowledge of its surrounding environment, a humanoid robot can generalize this knowledge to the case when it observes another agent (human partner) performing the same motor actions previously executed during training.Comment: code available at https://github.com/gsaponaro/glu-gesture

CRP Predicts Safe Patient Discharge after Colorectal Surgery. Reply

Reply: We would like to thank Aurelie´n Dupre`, Johan Gagnie´r, Heloı¨se Samba, Michel Rivoire, and Karem Slim for their comments about our article ‘‘Procalcitonin Reveals Early Dehiscence in Colorectal Surgery: The PREDICS Study.’’1 It is very rewarding to realize that this paper is stimulating so many observations, this means thatwe are talking about an interesting topic

The potential association between gingival crevicular fluid inflammatory mediators and adverse pregnancy outcomes: a systematic review

Objectives: The association between periodontal disease and adverse pregnancy outcomes (APO), primarily preterm birth (PTB), is still controversially discussed in the literature. Therefore, the aim of the present systematic review was to analyze the existing literature on the potential association between inflammatory mediators detected in gingival crevicular fluid (GCF) and APO. Materials and methods: MEDLINE (PubMed) and EMBASE databases were searched for entries up to April 2012 and studies were selected by two independent reviewers. Results: The majority of the eight studies included confirmed a positive association between GCF mediators, such as interleukin-1β, prostaglandin E2, and tumor necrosis factor-alpha, and APO. Due to the heterogeneity and variability of the available studies, no meta-analysis could be performed. Conclusions: A positive association between GCF inflammatory mediator levels and APO/PTB might be present but the results need to be considered with great caution because of the heterogeneity and variability among the studies. Further studies with an adequate number of patients allowing for an appropriate analysis are warranted to definitely confirm this association. Clinical relevance: The present findings suggest that an association between GCF inflammatory mediator levels and APO might exis

Peripheral blood regulatory T cell measurements correlate with serum vitamin D level in patients with psoriasis

OBJECTIVE:Vitamin D is the precursor of a hormone (1,25-dihydroxyvitamin D3), which has many biological effects in the skin. The immune modulator properties of vitamin D are mediated in part through effects on regulatory T cells (T-reg). Currently, in psoriasis, the relationship between vitamin D and T-reg has not well elucidated. We assess whether vitamin D status is correlated with circulating T-reg in patients affected by psoriasis and if there is a correlation with the severity of the disease evaluated with Psoriasis Area Severity Index (PASI) score. PATIENTS AND METHODS:For each patient we have analyzed, PASI-score, serum levels vitamin D and regulatory T cell percentages. Spearmen's coefficient was used between serum vitamin D levels and the predictors. Subsequently, the independent predictive factors were assessed by Multiple Regression. RESULTS:A total of 26 patients were included in our analysis. Using no parametric Spearman's Coefficient test between serum levels of vitamin D and the single variables, we found an association with T-reg population (p < 0.001) and with PASI-score (p = 0.04). CONCLUSIONS:While vitamin D treatment induces a cytokine profile known to favor the differentiation of T cells with suppressive activity, at the same time, several studies showed how vitamin D can prime for tolerogenic dendritic cells able to favor the differentiation of Treg from T naïve cells. Low levels of vitamin-D may decrease the number of circulatory T-reg, disrupting the immunological homeostasis in psoriatic patients and encouraging the inflammatory activity