Growth and social capital: an evolutionary model

In this paper, we analyze the role of cooperation between firms through a model of growth and social capital. In a growth model à la Solow we incorporate the set of resources that a relational network has at its disposals, as a distinct production factor, and thus examine its dissemination through evolutionary type processes in firm interactions. Dynamic analysis of the model demonstrates that cooperation is able to increase the productivity of factors, fostering a higher rate of growth in the long term. The most significant result is that scarcity of social capital can produce a general collapse of the economic system in areas in which long term growth is usually sustained by the learning by doing and spillover of knowledge phenomena. This conclusion leads to reconsider the role of local development economic policies that should concentrate on activities that promote repeated interaction between firms proven to be cooperative or that encourage the formation of technological consortia.Economic growth; Social capital; Networks; Evolutionary games

Homogeneous and inhomogeneous magnetic phases of constrained dipolar bosons

We study the emergence of several magnetic phases in dipolar bosonic gases subject to three-body loss mechanism employing numerical simulations based on the density matrix renormalization group(DMRG) algorithm. After mapping the original Hamiltonian in spin language, we find a strong parallelism between the bosonic theory and the spin-1 Heisenberg model with single ion anisotropy and long-range interactions. A rich phase diagram, including ferromagnetic, antiferromagnetic and non-local ordered phases, emerges in the half-filled one-dimensional case, and is preserved even in presence of a trapping potential.Comment: v2: 9 pages, 15 figures, extended version, new numerical calculations on the BKT transition, accepted for pubblication in PR

A Model of DC-DC Converter with Switched-Capacitor Structure for Electric Vehicle Applications

In this paper, a DC-DC converter with an innovative topology for automotive applications is proposed. The goal of the presented power converter is the electrical storage system management of an electric vehicle (EV). The presented converter is specifically compliant with a 400 V battery, which represents the high-voltage primary source of the system. This topology is also able to act as a bidirectional power converter, so that in this case, the output section is an active stage, which is able to provide power as, for example, in the case of a low-voltage battery or a supercapacitor. The proposed topology can behave either in step-down or in step-up mode, presenting in both cases a high gain between the input and output voltage. Simulation results concerning the proposed converter, demonstrating the early feasibility of the system, were obtained in a PowerSIM environment and are described in this paper

Specificity of Esthetic Experience for Artworks: An fMRI Study

In a previous functional magnetic resonance imaging (fMRI) study, where we investigated the neural correlates of esthetic experience, we found that observing canonical sculptures, relative to sculptures whose proportions had been modified, produced the activation of a network that included the lateral occipital gyrus, precuneus, prefrontal areas, and, most interestingly, the right anterior insula. We interpreted this latter activation as the neural signature underpinning hedonic response during esthetic experience. With the aim of exploring whether this specific hedonic response is also present during the observation of non-art biological stimuli, in the present fMRI study we compared the activations associated with viewing masterpieces of classical sculpture with those produced by the observation of pictures of young athletes. The two stimulus-categories were matched on various factors, including body postures, proportion, and expressed dynamism. The stimuli were presented in two conditions: observation and esthetic judgment. The two stimulus-categories produced a rather similar global activation pattern. Direct comparisons between sculpture and real-body images revealed, however, relevant differences, among which the activation of right antero-dorsal insula during sculptures viewing only. Along with our previous data, this finding suggests that the hedonic state associated with activation of right dorsal anterior insula underpins esthetic experience for artworks

Growth and social capital: an evolutionary model

In this paper, we analyze the role of cooperation between firms through a model of growth and social capital. In a growth model à la Solow we incorporate the set of resources that a relational network has at its disposals, as a distinct production factor, and thus examine its dissemination through evolutionary type processes in firm interactions. Dynamic analysis of the model demonstrates that cooperation is able to increase the productivity of factors, fostering a higher rate of growth in the long term. The most significant result is that scarcity of social capital can produce a general collapse of the economic system in areas in which long term growth is usually sustained by the learning by doing and spillover of knowledge phenomena. This conclusion leads to reconsider the role of local development economic policies that should concentrate on activities that promote repeated interaction between firms proven to be cooperative or that encourage the formation of technological consortia

Growth and social capital: an evolutionary model

In this paper, we analyze the role of cooperation between firms through a model of growth and social capital. In a growth model à la Solow we incorporate the set of resources that a relational network has at its disposals, as a distinct production factor, and thus examine its dissemination through evolutionary type processes in firm interactions. Dynamic analysis of the model demonstrates that cooperation is able to increase the productivity of factors, fostering a higher rate of growth in the long term. The most significant result is that scarcity of social capital can produce a general collapse of the economic system in areas in which long term growth is usually sustained by the learning by doing and spillover of knowledge phenomena. This conclusion leads to reconsider the role of local development economic policies that should concentrate on activities that promote repeated interaction between firms proven to be cooperative or that encourage the formation of technological consortia

Effects of Probiotics Supplementation on Risk and Severity of Infections in Athletes: A Systematic Review

The aim of this review was to appraise the literature on the effects of probiotics supplementation on gastrointestinal (GI) and upper respiratory tract infection (URTI) risk and prognosis in athletes. The search was conducted using the following electronic databases: MEDLINE (PubMed); Web of Science; Scopus; and SPORTDiscus (EBSCO). According to the PRISMA guidelines, randomized controlled studies performed on healthy athletes with a note dose of probiotics supplementation were considered. From the 2304 articles found, after eliminating reviews and studies on animals and unhealthy subjects and after screening of titles and abstracts, 403 studies were considered eligible. From these, in accordance with the inclusion and exclusion criteria, 16 studies were selected, ten of which concerned endurance athletes. The majority of the studies reported beneficial effects of probiotics in reducing the risk of developing the examined infections or the severity of related symptoms. However, due to the differences in formulations used and populations analyzed in the available studies, further research is needed in this field to achieve stronger and more specific evidence

Episodic memory and learning rates in amyotrophic lateral sclerosis without dementia

In amyotrophic lateral sclerosis (ALS), memory deficits may be primary or secondary to executive dysfunction. We assessed episodic memory and executive function of nondemented ALS patients, comparing episodic memory profiles and learning rates of ALS patients with those of mild cognitive impairment (MCI) subjects and cognitively healthy controls (HC). In a multidisciplinary tertiary centre for motor neuron disease, 72 nondemented ALS patients, 57 amnestic MCI (aMCI), 89 single non amnestic MCI with compromised executive functions (dysexecutive MCI), and 190 HC were enrolled. They were screened using the Frontal Assessment Battery and Mini Mental State Examination. Episodic memory performances and learning rates were tested using the Rey Auditory Verbal Learning Test (RAVLT). Episodic memory dysfunction (immediate recall) was found in 14 ALS patients (19.4%). The ALS group had lower performance than HC on immediate recall, without differences in learning rate, and better performance than aMCI subjects on all RAVLT measures. Compared to dysexecutive MCI subjects, ALS patients had only better verbal learning abilities. ALS patients with executive dysfunction had a lower score on immediate and delayed recalls, verbal learning, and primacy effect than ALS patients without executive dysfunction. The immediate recall among couples of diagnostic groups differed in a statistically significant way except for the ALS/dysexecutive MCI groups. In ALS patients, episodic memory performances and learning rates appeared to be better than in aMCI subjects and similar to those with dysexecutive MCI, suggesting also a secondary functional damage due to executive impairment

Predictors of recurrence after surgical treatment of idiopathic progressive subglottic stenosis

Predittori di recidiva dopo trattamento chirurgico delle stenosi idiopatiche subglottiche progressive. RIASSUNTO: La stenosi idiopatica subglottica progressiva rappresenta una rara causa di restringimento della laringe. La resezione parziale con successiva anastomosi pu\uf2 potenzialmente essere curativa; nonostante ci\uf2 alcuni pazienti richiedono un numero elevato di ritrattamenti e possono sviluppare disfonia e disfagia in seguito all\u2019intervento. In questo studio abbiamo investigato i fattori di rischio per il ritrattamento e abbiamo valutato l\u2019impatto della resezione crico-tracheale sui parametri funzionali. \uc8 stata condotta un\u2019analisi multicentrica retrospettiva su 44 pazienti di sesso femminile (et\ue0 media 52,6 \ub1 13,1 anni), sottoposti a resezione crico-tracheale tra il 2002 e il 2016. Gli esiti funzionali sono stati valutati utilizzando la scala \u201cvie aeree-dispnea-voce-disfagia\u201d dove ognuno di questi parametri \ue8 stato valutato con un punteggio da 1 a 5, ove 1 esprime una funzione normale e 5 una funzione completamente compromessa. L\u2019esistenza di trattamenti pregressi, il grado di stenosi, il sito della stenosi, la presenza di comorbidit\ue0 delle vie aeree, l\u2019et\ue0 e la lunghezza del segmento resecato sono stati testati all\u2019analisi bivariata e multivariata come predittori di complicanze e di trattamenti aggiuntivi. Il trattamento ha permesso la decannulazione del paziente nel 97,3% dei casi. L\u2019indice di dispnea \ue8 migliorato (variazione media 1,4 \ub1 1,0; p < 0,001), mentre quelli relativi alla voce e alla deglutizione sono peggiorati (variazione media 1,6 \ub1 0,9 and 0,5 \ub1 0,7, rispettivamente; p < 0,001). I pazienti affetti da comorbidit\ue0 delle vie aeree hanno presentato un tasso pi\uf9 alto di complicanze (p < 0,05). La lunghezza del segmento resecato ha dimostrato una correlazione diretta con il numero dei ritrattamenti (R = 0,52; p < 0,01). All\u2019analisi multivariata, le complicazioni post-operatorie erano predette dall\u2019esistenza di comorbidit\ue0 e dallo stadio di malattia (p < 0,05); il numero dei ritrattamenti era associato alla lunghezza del tratto resecato (p < 0,05) e all\u2019applicazione di Mitomicina C (p < 0,001). La resezione crico-tracheale offre dei buoni risultati funzionali per la cura della stenosi idiopatica subglottica progressiva, in termini di perviet\ue0 delle vie aeree. I nostri dati suggeriscono che i pazienti affetti da comorbidit\ue0 possono presentare un\u2019incidenza pi\uf9 alta di complicazioni. Inoltre, resezioni chirurgiche pi\uf9 estese sembrano essere associate all\u2019incidenza e al numero dei ritrattamenti. Al contrario, l\u2019applicazione di sostanza anti-proliferativa non sembra essere utile nella prevenzione delle recidive.Idiopathic progressive subglottic stenosis is a rare cause of tracheal narrowing. Partial cricotracheal resection and anastomosis can cure idiopathic stenosis, even if some patients may require multiple interventions and experience voice and swallowing deterioration. We investigated risk factors for retreatment and assessed the impact of crico-tracheal resection on functional parameters. We conducted a retrospective multicentric study on 44 female patients (mean age 52.6 \ub1 13.1 years) affected by idiopathic stenosis and treated by crico-tracheal resection between 2002 and 2016. Functional outcomes after crico-tracheal resection were assessed by the airway-dyspnoea-voice-swallowing score (range 1-5, with "1" expressing normal and "5" completely altered function). Previous treatments, grade of stenosis, site, airway comorbidities, age and resection length were tested as predictors of postoperative complications and number of additional treatments, using bivariate and multivariate analysis. The overall decannulation rate was 97.3%. The dyspnoea score improved (mean variation 1.4 \ub1 1.0; p < 0.001), while voice and swallowing were negatively affected (mean variation 1.6 \ub1 0.9 and 0.5 \ub1 0.7, respectively; p < 0.001). Airway comorbidities were associated with a higher rate of complications (p < 0.05). Retreatments were more frequent in patients with postoperative complications (p < 0.05). The length of resection correlated with the number of subsequent treatments (R = 0.52; p < 0.01). At multivariate analysis, post-operative complications were predicted by comorbidities and disease stage (p < 0.05); number of retreatments was linked to the length of resection (p < 0.05) as well as with the application of mitomycin C (p < 0.001). Crico-tracheal resection for idiopathic progressive subglottic stenosis offers good functional results in terms of airway patency. These data suggest that a higher complication rate can be expected in patients affected by comorbidities. Moreover, more extensive surgical resection seems to be associated with the occurrence and number of subsequent retreatments. On the contrary, the local application of an anti-proliferative drug does not seem to be of use in preventing recurrences