Evaluation and metrics framework

In this paper a metrics framework for evaluating different scenarios in the CATNETS project is defined. The aim is to use this framework to compare the catallactic scenario against the central auctioneer. --Grid Computing

Uncertainty, rationality and complexity in a multi-sectoral dynamic model: The dynamic stochastic generalized aggregation approach

The paper proposes an innovative approach for the analytical solution of agent-based models. The approach is termed dynamic stochastic generalized aggregation (DSGA) and is tested on a macroeconomic model articulated in a job and in a goods markets with a large number of heterogeneous and interacting agents (namely firms and workers). The agents heuristically adapt their expectations by interpreting the signals from the market and give rise to macroeconomic regularities. The model is analytically solved in two different scenarios. In the first, the emergent properties of the system are determined uniquely by the myopic behavior of the agents while, in the second, a social planner quantifies the optimal number of agents adopting a particular strategy. The integration of the DSGA approach with intertemporal optimal control allows the identification of multiple equilibria and their qualitative classification

Imaging follow-up after liver transplantation

Liver transplantation (LT) represents the best treatment for end-stage chronic liver disease, acute liver failure and early stages of hepatocellular carcinoma. Radiologists should be aware of surgical techniques to distinguish a normal appearance from pathological findings. Imaging modalities, such as ultrasound, CT and MR, provide for rapid and reliable detection of vascular and biliary complications after LT. The role of imaging in the evaluation of rejection and primary graft dysfunction is less defined. This article illustrates the main surgical anastomoses during LT, the normal appearance and complications of the liver parenchyma and vascular and biliary structures.Liver transplantation (LT) represents the best treatment for end-stage chronic liver disease, acute liver failure and early stages of hepatocellular carcinoma. Radiologists should be aware of surgical techniques to distinguish a normal appearance from pathological findings. Imaging modalities, such as ultrasound, CT and MR, provide for rapid and reliable detection of vascular and biliary complications after LT. The role of imaging in the evaluation of rejection and primary graft dysfunction is less defined. This article illustrates the main surgical anastomoses during LT, the normal appearance and complications of the liver parenchyma and vascular and biliary structures

Climate-change adaptation: The role of fiscal policy

Climate change and natural disasters have important consequences on fiscal sustainability, especially for developing countries with limited financial resources and underdeveloped institutions. The paper contributes to shed light on the role of fiscal policy in climate-change adaptation, which aims at containing the economic damage of climate change. We use an overlapping generations (OLG) model for a small open economy in which adaptation reflects the extent to which public policies reduce the negative influence of climate change on the capital depreciation rate. Adaptation includes both preventive measures, i.e. investment in infrastructure, and remedial measures, i.e. post-disaster relief and reconstruction. Through model simulations we assess the costs and benefits of both remedial and preventive actions. We find that preventive intervention leads to higher GDP growth rates than either taking no action or waiting until remedial action is necessary. However, the evidence shows that, due to high costs of early adaptation and budgetary constraints, countries tend to focus on late corrective actions, also relying on international assistance. Given the expected increase in climate-related risks, a comprehensive strategy including both preventive and corrective actions would be desirable to strengthen resilience to shocks and alleviate the financial constraints, which particularly affect small countries

Communicating oesophageal duplication: a case report

ions of the oesophagus are rare congenital abnormalities and rarely comunicate with the oesophageal lumen. They are com - monly associated with other congenital malformations, such as spinal deformities, congenital heart disease, vertebral anomalies, malrota - tion of the bowel, Meckel’s diverticulum. During a percutaneous endoscopic gastrostomy, performed becau - se of a neurological dysphagia, the endoscopy revealed a very rare case of a 26-year old man affected by Klippel-Trenaunay syndrome, with an asymptomatic oesophageal duplication that communicated proxi - mally and distally

I modelli ad agenti come strumento per la microfondazione della macroeconomia

Nella tesi vengono discussi i presupposti teorici, lo sviluppo, e le proprietà analitiche ed emergenti di due modelli ad agenti per la simulazione di un’economia artificiale composta dai mercati del bene di consumo, del lavoro e del credito. Lo scopo è quello di costituire una piattaforma per l’analisi della micro-fondazione macroeconomica seguendo una tradizione teorica non standard. Ad introduzione precede una dettagliata rassegna della letterattura dei modello ad agenti con particolare rilievo per i modelli macroeconomici apparsi in letteratur

Comparison of magnetic resonance spectroscopy, proton density fat fraction and histological analysis in the quantification of liver steatosis in children and adolescents

AIM: To establish a threshold value for liver fat content between healthy children and those with non-alcoholic fatty liver disease (NAFLD) by using magnetic resonance imaging (MRI), with liver biopsy serving as a reference standard. METHODS: The study was approved by the local ethics committee, and written informed consent was obtained from all participants and their legal guardians before the study began. Twenty-seven children with NAFLD underwent liver biopsy to assess the presence of nonalcoholic steatohepatitis. The assessment of liver fat fraction was performed using MRI, with a high field magnet and 2D gradient-echo and multiple-echo T1-weighted sequence with low flip angle and single-voxel point-resolved ¹H MR-Spectroscopy (¹H-MRS), corrected for T1 and T2* decays. Receiver operating characteristic curve analysis was used to determine the best cut-off value. Lin coefficient test was used to evaluate the correlation between histology, MRS and MRI-PDFF. A Mann-Whitney U-test and multivariate analysis were performed to analyze the continuous variables. RESULTS: According to MRS, the threshold value between healthy children and those with NAFLD is 6%; using MRI-PDFF, a cut-off value of 3.5% is suggested. The Lin analysis revealed a good fit between the histology and MRS as well as MRI-PDFF. CONCLUSION: MRS is an accurate and precise method for detecting NAFLD in children

The decline in muscle strength and muscle quality in relation to metabolic derangements in adult women with obesity

Background & aims: The metabolic and functional characteristics related to sarcopenic obesity have not been thoroughly explored in the earlier stages of the aging process. The aim of the present study was to examine the phenotype of sarcopenic obesity, in terms of lean body mass, muscle strength and quality, in adult women with and without the Metabolic Syndrome (MetS), and its relationship with the features of myosteatosis. Methods: Study participants were enrolled at the Sapienza University, Rome, Italy. Body composition was assessed by DXA. The Handgrip strength test (HGST) was performed. HGST was normalized to arm lean mass to indicate muscle quality; intermuscular adipose tissue (IMAT) and intramyocellular lipid content (IMCL) were measured by magnetic resonance imaging and spectroscopy, as indicators of myosteatosis. Different indices of sarcopenia were calculated, based on appendicular lean mass (ALM, kg) divided by height squared, or weight. The NCEP-ATPIII criteria were used to diagnose the MetS. HOMA-IR was calculated. The physical activity level (PAL) was assessed through the IPAQ questionnaire. Results: 54 women (age: 48 ± 14 years, BMI: 37.9 ± 5.4 kg/m 2 ) were included. 54% had the MetS (metabolically unhealthy, MUO). HGST/arm lean mass was lower in MUO women than women without the MetS (6.3 ± 1.8 vs. 7.8 ± 1.6, p = 0.03). No differences emerged in terms of absolute ALM (kg) or other indices of sarcopenia (ALM/h 2 or ALM/weight) between metabolically healthy (MHO) vs. MUO women (p > 0.05). Muscle quality was negatively associated with HOMA-IR (p = 0.02), after adjustment for age, body fat, hs-CRP levels, and PAL. IMAT, but not IMCL, was significantly higher in obese women with the MetS compared to women without the MetS (p > 0.05). No association emerged between HGST/arm lean mass and IMAT or IMCL when HOMA-IR was included in the models. Conclusion: Insulin resistance, and not sarcopenia or myosteatosis per se, was associated with muscle weakness, resulting in the phenotype of “dynapenic obesity” in middle-aged women with the metabolic syndrome

Industrial dynamics, fiscal policy and R&D: evidence from a computational experiment

We present an agent-based computational model in which bounded rational firms and workers trade on fully decentralized markets for final goods and labor by means of random matching protocols. The model replicates several macroeconomic phenomena regularly observed in the data, with aggregate features emerging from the localized interactions of individual entities. The model is then used as a computational laboratory to run an experiment on the role of fiscal policy in increasing macroeconomic performance