Investigation of the feasibility to use Zeeman-effect background correction for the graphite furnace determination of phosphorus using high-resolution continuum source atomic absorption spectrometry as a diagnostic tool

The determination of phosphorus by graphite furnace atomic absorption spectrometry at the non-resonance line at 213.6 nm, and the capability of Zeeman-effect background correction (Z-BC) to deal with the fine-structured background absorption due to the PO molecule have been investigated in the presence of selected chemical modifiers. Two line source atomic absorption spectrometers, one with a longitudinally heated and the other with a transversely heated graphite tube atomizer have been used in this study, as well as two prototype high-resolution continuum source atomic absorption spectrometers, one of which had a longitudinally arranged magnet at the furnace. It has been found that Z-BC is capable correcting very well the background caused by the PO molecule, and also that of the NO molecule, which has been encountered when the Pd + Ca mixed modifier was used. Both spectra exhibited some Zeeman splitting, which, however, did not cause any artifacts or correction errors. The practical significance of this study is to confirm that accurate results can be obtained for the determination of phosphorus using Z-BC. The best sensitivity with a characteristic mass of m(0) = 11 ng P has been obtained with the pure Pd modifier, which also caused the lowest background level. The characteristic mass obtained with the mixed Pd + Ca modifier depended on the equipment used and was between m(0) = 9 ng P and m(0) = 15 ng P, and the background signal was higher. The major problem of Z-BC remains the relatively restricted linear working range

Collaborative creativity: The Music Room

In this paper, we reflect on our experience of designing, developing and evaluating interactive spaces for collaborative creativity. In particular, we are interested in designing spaces which allow everybody to compose and play original music. The Music Room is an interactive installation where couples can compose original music by moving in the space. Following the metaphor of love, the music is automatically generated and modulated in terms of pleasantness and intensity, according to the proxemics cues extracted from the visual tracking algorithm. The Music Room was exhibited during the EU Researchers' Night in Trento, Italy

Failure of cerebral postural blood flow autoregulation in the elderly as a cause of cerebral orthostatic ischemia

The variations of continuous wave Doppler S/T index of internal carotid artery, reflecting changes of cerebral blood flow, were studied during an orthostatic test in elderly patients with typical orthostatic hypotension and in elderly patients with symptoms of cerebral ischemia when standing, but without diagnostic falls in blood pressure. The observation of a significant decrease of Doppler S/T index in both groups of patients confirms the hypothesis that a failure of cerebral postural blood flow regulation may be a primary mechanism of orthostatic cerebral ischemia, explaining why clinical symptoms of this condition can develop in some elderly patients, when standing, with minor or no falls in blood pressure

The role of personality in shaping social networks and mediating behavioral change

In this paper, we exploit different facets of the Friends and Family study to deal with two personality-related tasks of paramount importance for the user modeling and ubiquitous computing fields. First, we propose and validate an approach for automatic classification of personality traits based on the ego-networks’ structural characteristics. Our classification results show that (i) mobile phones-based behavioral data can be superior to survey ones for the purposes of personality classification from structural network properties and (ii) particular feature set/network type combinations promise to perform better with given personality traits. Then, we investigate the mediating role played by personality in the context of inducing behavioral change, specifically increasing daily physical activity using social strategies (social comparison and peer pressure). Our results confirm the role played by Extraversion and Neuroticism. Extroverts exposed to a social comparison strategy are positively associated with an increase in physical activity level, while they tend to decrease physical activity level if they are exposed to a peer pressure intervention strategy. Regarding Neuroticism dimension, neurotic people tend to increase their physical daily activity level if they are exposed to a social comparison strategy. Our findings may have implications in designing personality-based behavioral change strategies and suggest to incorporate users’ personality models in the implementation of persuasive systems

Economic evaluation of HIV treatments: The I.CO.N.A. cohort study

Objective: To describe the changes in costs of care for HIV-positive patients in Italy after the spread of antiretroviral combination therapies (HAART).Methods: Five thousand four hundred and twenty-two patients from the I.CO.N.A. (Italian Cohort Naive Antiretrovirals) study were followed between 1997 and 2002. Costs included antiretroviral therapies (ART), hospital admissions, prophylaxis, and main laboratory examinations. The perspective was that of the National Health Service.Results: Admission costs per person-year decreased from 2148 euro in 1997 to 256 in 2002, while the average annual costs of ART increased from 2145 to 3149 euro (1997 prices). From 1997 to1999, ART costs increased from 42.3 to 85.9 of the total, while admission costs decreased from 42.3 to 7.0 and prophylaxis from 7.3 to 1.7. The breakdown of ART costs shows how dual therapies decreased over time in favor of HAART, falling from 26.8 in 1997 to 5.9 in 2002. Patients with fewer than five treatment switches had the lowest costs distributions over the entire observation period.Conclusions: From 1997 to 2002 inpatient costs progressively decreased in favor of antiretroviral therapy. Annual average costs per patient decreased, while total direct costs increased over time: health resources, initially concentrated on hospitalized patients were then distributed over a growing number of subjects