Archeologia e Web 2.0. Verità e dinamiche di potere nell’era digitale

The development of new media for use as tools to collect, register and create data has opened innovative and original mediascapes where several forces are involved in an effort to provide a historical explanation of the past. Augmented reality is not a simple virtual object but is also a historical fact, which has modified the offline world. The huge amount of data poured into cyberspace have multiplied the actors involved in the construction of historical and archaeological interpretations and produced different discourses in competition with each other about the past. The ‘democratization’ of knowledge conveyed by the web has opened new semantic spaces and challenged the old rules about authority of knowledge. Today, archaeology must deal with the logic inherent in these new rhetoric spaces and with its particular way of making discourse about the past through the web

Effect of Poisson ratio on cellular structure formation

Mechanically active cells in soft media act as force dipoles. The resulting elastic interactions are long-ranged and favor the formation of strings. We show analytically that due to screening, the effective interaction between strings decays exponentially, with a decay length determined only by geometry. Both for disordered and ordered arrangements of cells, we predict novel phase transitions from paraelastic to ferroelastic and anti-ferroelastic phases as a function of Poisson ratio.Comment: 4 pages, Revtex, 4 Postscript figures include

Exploring efficient imperative handover mechanisms for heterogeneous wireless networks

The Next Generation Internet will provide ubiquitous computing by the seamless operation of heterogeneous wireless networks. It will also provide support for quality-ofservice, QoS, fostering new classes of applications and will havea built-in multi-level security environment. A key requirement of this new infrastructure will be support for efficient vertical handover. Y-Comm is a new architecture that will meet the challenge of this new environment. This paper explores the design of efficient imperative handover mechanisms using the Y-Comm Framework. It first looks at different types of handovers, then examines the Y-Comm Framework and shows how Y-Comm maps unto current mobile infrastructure. It then explores support for different handover mechanisms using Y-Comm. Finally, it highlights the development of a new testbed to further investigate the proposed mechanisms

A QoS framework for heterogeneous networking

In order for next generation networks to support effective handover procedures, there is a need for defining QoS signaling mechanisms that guarantee the provision of point- to- point as well as network level QoS. This paper proposes a QoS signaling mechanism to be implemented by the Y-Comm architecture as a potential 4G framework. The proposed mechanism requires certain level of cooperation among network elements; therefore, it proposes some functional modules/ interfaces to be run on different network entities. As showed in the paper, the proposed mechanism could be implemented in different scenarios such as initial registration and connection, and also in the case of handover

Information for handover management in heterogeneous networks: data representation,languages and integrated platforms

Due to the convergence of radio, television, telephony and Internet areas, the mobility of users, the ubiquity of services, and the development of new technologies to unify access provision, the interaction between providers and users will be required for access on demand in heterogeneous environments. This interaction should allow, in addition to seamless handovers, the negotiation based on technical requirements and user's desires during handover decision processes. The central part of the information being exchanged between the access provider's attachment points and user's devices should be a uniform and common structure that models the handover management information, in terms of what the information represents their semantic meanings and relationships. This work presents a set of ontologies, for this purpose, employed during handover decision processes, in integrated networking platforms for access on demand. A case study is presented, which demonstrates how a service could be integrated in two different platforms for such environment

The combination of liver stiffness measurement and NAFLD fibrosis score improves the noninvasive diagnostic accuracy for severe liver fibrosis in patients with nonalcoholic fatty liver disease.

BACKGROUND & AIMS: The accuracy of noninvasive tools for the diagnosis of severe fibrosis in patients with nonalcoholic fatty liver disease(NAFLD) in clinical practice is still limited. We aimed at assessing the diagnostic performance of combined noninvasive tools in two independent cohorts of Italian NAFLD patients. METHODS: We analysed data from 321 Italian patients(179 Sicilian-training cohort, and 142 northern Italy-validation cohort) with an histological diagnosis of NAFLD. Severe fibrosis was defined as fibrosis ≥ F3 according to Kleiner classification. The APRI, AST/ALT, BARD, FIB-4, and NFS scores were calculated according to published algorithms. Liver stiffness measurement(LSM) was performed by FibroScan. Cut-off points of LSM, NFS and FIB-4 for rule-in or rule-out F3-F4 fibrosis were calculated by the reported formulas. RESULTS: In the Sicilian cohort AUCs of LSM, NFS, FIB-4, LSM plus NFS, LSM plus FIB-4, and NFS plus FIB-4 were 0.857, 0.803, 0.790, 0.878, 0.888 and 0.807, respectively, while in the northern Italy cohort the corresponding AUCs were 0.848, 0.730, 0.703, 0.844, 0.850, and 0.733 respectively. In the training cohort, the combination of LSM plus NFS was the best performing strategy, providing false positive, false negative and uncertainty area rates of 0%,1.1% and 48% respectively. Similar results were obtained in the validation cohort with false positive, false negative and uncertainty area rates of 0%,7.3% and 40.8%. CONCLUSIONS: The combination of LSM with NFS, two complementary, easy-to-perform, and widely available tools, is able to accurately diagnose or exclude the presence of severe liver fibrosis, also reducing of about 50-60% the number of needed diagnostic liver biopsies