Subdynamics of relevant observables: a field theoretical approach

An approach to the description of subdynamics inside non-relativistic quantum field theory is presented, in which the notions of relevant observable, time scale and complete positivity of the time evolution are stressed. A scattering theory derivation of the subdynamics of a microsystem interacting through collisions with a macrosystem is given, leading to a master-equation expressed in terms of the operator-valued dynamic structure factor, a two-point correlation function which compactly takes the statistical mechanics properties of the macrosystem into account. For the case of a free quantum gas the dynamic structure factor can be exactly calculated and in the long wavelength limit a Fokker-Planck equation for the description of quantum dissipation and in particular quantum Brownian motion is obtained, where peculiar corrections due to quantum statistics can be put into evidence.Comment: 28 pages, latex, no figure

Visual working memory in immersive visualization: a change detection experiment and an image-computable model

Visual working memory (VWM) is a cognitive mechanism essential for interacting with the environment and accomplishing ongoing tasks, as it allows fast processing of visual inputs at the expense of the amount of information that can be stored. A better understanding of its functioning would be beneficial to research fields such as simulation and training in immersive Virtual Reality or information visualization and computer graphics. The current work focuses on the design and implementation of a paradigm for evaluating VWM in immersive visualization and of a novel image-based computational model for mimicking the human behavioral data of VWM. We evaluated the VWM at the variation of four conditions: set size, spatial layout, visual angle (VA) subtending stimuli presentation space, and observation time. We adopted a full factorial design and analysed participants' performances in the change detection experiment. The analysis of hit rates and false alarm rates confirms the existence of a limit of VWM capacity of around 7 & PLUSMN; 2 items, as found in the literature based on the use of 2D videos and images. Only VA and observation time influence performances (p<0.0001). Indeed, with VA enlargement, participants need more time to have a complete overview of the presented stimuli. Moreover, we show that our model has a high level of agreement with the human data, r>0.88 (p<0.05)

A VSA-SS Approach to Healthcare Service Systems. The Triple Target of Efficiency, Effectiveness and Sustainability

The main purpose of this paper is to highlight the new opportunities that the Viable Systems Approach (VSA) can provide for observing complex service systems and explaining social phenomena through general schemes of interpretation. At the same time, it explores methodological links with the Service Science (SS) approach in order to propose (VSA)’s contribution to moulding a unified vision of complex objects of analysis, and to evidence the many converging elements that emerge from the two perspectives as well as the benefits that derive from different interpretation schemes. In particular, in our paper we analyze healthcare service complexity in a relational perspective, using a VSA-SS conceptual framework to interpret the emergent systems instability in the Italian Health Service. The application of principles and concepts proper to the (VSA) and the SS approaches to articulated service structures, such as healthcare, identifies critical features and interesting new “therapeutic” prospects for healthcare service systems in order to guarantee their viability. The paper proposes an innovative methodological basis for evaluating the level of appropriateness of the healthcare service and, at the same time, evidences the need for achieving a balanced triple target of efficiency, effectiveness and sustainability (EES) in healthcare service systems governance. As a result, a new area of cross fertilization for collaborative research emerges

Visualization and Interaction Technologies in Serious and Exergames for Cognitive Assessment and Training: A Survey on Available Solutions and Their Validation

Exergames and serious games, based on standard personal computers, mobile devices and gaming consoles or on novel immersive Virtual and Augmented Reality techniques, have become popular in the last few years and are now applied in various research fields, among which cognitive assessment and training of heterogeneous target populations. Moreover, the adoption of Web based solutions together with the integration of Artificial Intelligence and Machine Learning algorithms could bring countless advantages, both for the patients and the clinical personnel, as allowing the early detection of some pathological conditions, improving the efficacy and adherence to rehabilitation processes, through the personalisation of training sessions, and optimizing the allocation of resources by the healthcare system. The current work proposes a systematic survey of existing solutions in the field of cognitive assessment and training. We evaluate the visualization and interaction technologies commonly adopted and the measures taken to fulfil the need of the pathological target populations. Moreover, we analyze how implemented solutions are validated, i.e. The chosen experimental designs, data collection and analysis. Finally, we consider the availability of the applications and raw data to the large community of researchers and medical professionals and the actual application of proposed solutions in the standard clinical practice. Despite the potential of these technologies, research is still at an early stage. Although the recent release of accessible immersive virtual reality headsets and the increasing interest on vision-based techniques for tracking body and hands movements, many studies still rely on non-immersive virtual reality (67.2%), mainly mobile and personal computers, and standard gaming tools for interactions (41.5%). Finally, we highlight that although the interest of research community in this field is increasingly higher, the sharing of dataset (10.6%) and implemented applications (3.8%) should be promoted and the number of healthcare structures which have successfully introduced the new technological approaches in the treatment of their host patients is limited (10.2%)

The Impact of Specific Viruses on Clinical Outcome in Children Presenting with Acute Heart Failure

Abstract: The presence and type of viral genomes have been suggested as the main etiology for inflammatory dilated cardiomyopathy. Information on the clinical implication of this finding in a large population of children is lacking. We evaluated the prevalence, type, and clinical impact of specific viral genomes in endomyocardial biopsies (EMB) collected between 2001 and 2013 among 63 children admitted to our hospital for acute heart failure (median age 2.8 years). Viral genome was searched by polymerase chain reaction (PCR). Patients underwent a complete two-dimensional echocardiographic examination at hospital admission and at discharge and were followed-up for 10 years. Twenty-seven adverse events (7 deaths and 20 cardiac transplantations) occurred during the follow-up. Viral genome was amplified in 19/63 biopsies (35%); PVB19 was the most commonly isolated virus. Presence of specific viral genome was associated with a significant recovery in ejection fraction, compared to patients without viral evidence (p < 0.05). In Cox-regression analysis, higher survival rate was related to virus-positive biopsies (p < 0.05). When comparing long-term prognosis among different viral groups, a trend towards better prognosis was observed in the presence of isolated Parvovirus B19 (PVB19) (p = 0.07). In our series, presence of a virus-positive EMB (mainly PVB19) was associated with improvement over time in cardiac function and better long-term prognosis

Misura dei cambiamenti paesaggistici in ambiente alpino attraverso l&#8217;integrazione di dati telerilevati

Dalla met\ue0 del secolo scorso il paesaggio italiano ha subito delle profonde trasformazioni dovute al cambiamento di uso/copertura del suolo con la perdita di prati e pascoli a causa dei naturali processi di successione forestale, con forti ripercussioni sulla conservazione della biodiversit\ue0 (Falcucci et al. 2006). Gli ecosistemi alpini sono particolarmente sensibili a queste modifiche (Gehrig-Fasel et al. 2007) a causa dell\u2019elevato grado di endemismi fortemente adattati (Billings 1974). Per attuare delle misure di tipo conservazionistico, quindi \ue8 fondamentale quantificare il cambiamento di copertura del suolo avvenuto negli ultimi decenni ed impostare un monitoraggio a lungo termine delle strutture vegetali per individuare le aree maggiormente sensibili

Syngas production, clean-up and wastewater management in a demo-scale fixed-bed updraft biomass gasification unit

This paper presents the experimental development at demonstration scale of an integrated gasification system fed with wood chips. The unit is based on a fixed-bed, updraft and air-blown gasifier-with a nominal capacity of 5 MWth-equipped with a wet scrubber for syngas clean-up and an integrated chemical and physical wastewater management system. Gasification performance, syngas composition and temperature profile are presented for the optimal operating conditions and with reference to two kinds of biomass used as primary fuels, i.e., stone pine and eucalyptus from local forests (combined heat and power generation from this kind of fuel represents a good opportunity to exploit distributed generation systems that can be part of a new energy paradigm in the framework of the circular economy). The gasification unit is characterised by a high efficiency (about 79-80%) and an operation stability during each test. Particular attention has been paid to the optimisation of an integrated double stage wastewater management system-which includes an oil skimmer and an activated carbon adsorption filter-designed to minimise both liquid residues and water make-up. The possibility to recycle part of the separated oil and used activated carbon to the gasifier has been also evaluated

Reproductive payoffs of territoriality are snow-dependent in a mountain ungulate, the Alpine chamois

Female density and distribution are dependent on resource phenology and female availability strongly influences male mating behaviour and success. When a male adopts a ‘resource defence’ tactic, his reproductive success depends on the location and attractiveness of his territory. Environmental factors associated with territory quality are expected to influence mating success, for example, through territory features or male–male competition. In a protected population of a mountain-dwelling polygynous herbivore, the Alpine chamois Rupicapra r. rupicapra, we investigated the relationships among mating opportunities, some environmental variables (snow depth, topographic features and size of territories) and male intra-sexual competition for mating. We recorded the mating behaviour and territory size of 15 GPS-GSM radio-tagged territorial males, during five rutting seasons (early November to early December: N = 8 individuals in 2011, N = 9 in 2012, N = 8 in 2015, N = 11 in 2016, N = 7 in 2017; 80% of them were observed for more than one mating season) and related them to snow depth and topography of territories. In ruts with deep snow cover, territorial males had smaller territories and higher number of mating opportunities than in ruts with lower snow cover. Smaller territories showed the highest values of terrain roughness, in turn with little or no snow cover in the mating season, and were visited by a greater number of females, than larger territories. Number of wins was positively influenced by snow depth and negatively related to the frequency of aggressions. The frequency of male–male aggressive interactions was greater during ruts with deep snow cover and for males with territories at higher elevations; additionally, it was negatively related to interactions won. Thus, snow depth, which influences resource distribution and female movements, is confirmed as a strong determinant of male mating opportunities and mating behaviour

Patterns of spatio-temporal change in Alpine ibex (Capra ibex ibex, L.) distribution in Gran Paradiso National Park

Ibex is the symbolic species of mountain ungulates and currently it is classified at Least Concern by IUCN. In the last few decades there was a drastic decrease in population abundance linked with a reduction of stable occupied territories. Causes are still not completely clear but drastic decline is in partly due to recent climate changes. The objectives of this study are to analyse the ibex distribution changes in Gran Paradiso National Park (GPNP) in 1985-2014 period, the type of relation between pattern of distribution and population trend and finally the evidence of most used ibex \u2018s territories in GPNP. To understand distribution patterns ibex census data are been analysed using metrics belonging to landscape ecology, an approach based on the notion that environmental patterns influence ecological processes. In particular 5 metrics are been used to assess the composition and spatial configuration of occupied areas, while distribution statistics provided a statistical summaries of obtained results. Results showed a reduction of ibex occupied territories from 4587.50 ha in 1985 to 2437.50 ha in 2014 and fragmentation of ibex occupied territories with a strong increase in number of occupied patches from 130 units to 229 units. We suggest that likely ibex distribution was influenced by different combined factors (landscape change, climate change, anthropic activities), which have to be still examined in depth. Landscape ecology approach may become an useful tool to understand the degree of fragmentation and connectivity of landscape defined on species distribution. The understanding of processes behind Alpine ungulates distribution have to consider the influence of landscape patterns on environmental processes to improve the conservation efforts at management level