GUIDELINES FOR A DIGITAL REINTERPRETATION OF ARCHITECTURAL RESTORATION WORK: REALITY-BASED MODELS AND REVERSE MODELLING TECHNIQUES APPLIED TO THE ARCHITECTURAL DECORATION OF THE TEATRO MARITTIMO, VILLA ADRIANA

The Maritime Theatre is one of the iconic buildings of Hadrian's Villa, Tivoli. The state of conservation of the theatre is not only the result of weathering over time, but also due to restoration work carried out during the Fifties of the past century. Although this anastylosis process had the virtue of partially restoring a few of the fragments of the compound's original image, it now reveals diverse inconsistencies and genuine errors in the reassembling of the fragments. This study aims at carrying out a digital reinterpretation of the restoration of the architectural fragments in relation to the architectural order, with particular reference to the miscellaneous decoration of the frieze of the Teatro Marittimo (vestibule and atrium). Over the course of the last few years the Teatro Marittimo has been the target of numerous surveying campaigns using digital methodology (laser scanner and photogrammetry SfM/MVS). Starting with the study of the remains of the opus caementicium on the ground, it is possible to identify surfaces which are then used in the model for subsequent cross sections, so as to achieve the best fitting circumferences to use as reference points to put the fragments back into place

AN OPTIMISED WORKFLOW FOR THE INTERACTIVE EXPERIENCE WITH CULTURAL HERITAGE THROUGH REALITY-BASED 3D MODELS: CASES STUDY IN ARCHAEOLOGICAL AND URBAN COMPLEXES

The paper compares two workflows for the achievement of 3D models aimed at in-depth studies on the geometric features of Cultural Heritage artefacts and their dissemination. The purpose is the outlining of pros and cons of different techniques coming from entertainment and video games industry, starting from highly reliable 3D documentation of cultural assets, i.e. architectural/archaeological/urban sites. Two different possible applications are described: (i) procedural modelling used for understanding and visualising reconstruction hypotheses of the vaulted pavilions at Hadrian’s Villa, Tivoli, Rome; (ii) optimisation of 3D high-detailed models, as input files, turned into visual reliable and highly portable assets for game-engines. The first case study is focussed on creating a flexible model for evalueting reconstruction hypotheses and supplying restorers with useful hints for shape completion of ruined pavilions. The second case study makes available detailed digital contents for storytelling historical and cultural events in an attractive way, as in the case of the urban explorative model of Chiuro, a small town in northern Italy

VEGETATION LANDSCAPE MANAGEMENT OF “NATURAL RESERVE OF CHIARONE”, MASSACIUCCOLI LAKE BASIN (TUSCANY, IT)

The Massaciuccoli Lake is located in NW of Tuscany (Italy) (43°50’N 10°19’E) and it is integral part of the Regional Park of San Rossore, Migliarino and Massaciuccoli. This endorheic lake and the surrounding marshlands, with over 2,000 hectares of surface, form the largest retrodunal wetland of Tuscany. Over the last century this ecological system has undergone profound changes both because of land drainage, both because of the industrial and agricultural development of the surrounding areas that have heavily polluted lake, whose waters are still affected by serious eutrophication and ecological degradation. In order to preserve the great natural value of the lake in 1979, with the birth of the regional protected area, was established in the marshy area around the village of Massaciuccoli, the "Natural Reserve of Chiarone"(100 ha). Since 1985 the association LIPU (Italian League for Bird Protection) has obtained the management of the reserve, and its activity is directed to purposes of environmental education, environmental restoration, monitoring and conservation of specific habitats. This report shows the results of several years of investigation on the main vegetational types and their diachronic tranformations, the presence and distribution of endemic/rare/protected species, the changes on the structure of floating islands of peats and the main actions of conservation and management of these wetlands. The vegetation landscape is mainly formed by a mosaic of Phragmitetum australis Gams 1927, Cladietum marisci (Allorge 1922) Zobrist 1935, Typhetum angustifoliae Pignatti 1953, Myriophyllo-Nupharetum Koch 1926, and a large spread of microwoods of hygrophilous phanerophytes as Alnus glutinosa, Frangula alnus, Salix sp.pl. A particular aspect of this lake environment are the "aggallati", floating islands of peat incurred by intertwining rhizomes of straws. Above these peatlands often develop communities of Sphagnum sp.pl, Osmunda regalis L. and Thelypteris palustris Schott (Fig.1). The monitoring of these environments has highlighted the importance of ongoing management, in relation to the maintenance of certain habitats, through periodic cuttings, such as Sphagnum bogs, the control of exotic fauna such as Myocastor coypus, particularly damaging for Cladietum meadows and the special maintenance of the islands, whose structural peculiarity has lately been severely damaged catastrophic weather event

Some results and problems for anisotropic random walks on the plane

This is an expository paper on the asymptotic results concerning path behaviour of the anisotropic random walk on the two-dimensional square lattice Z^2. In recent years Mikl\'os and the authors of the present paper investigated the properties of this random walk concerning strong approximations, local times and range. We give a survey of these results together with some further problems.Comment: 20 page

Random walks on combs

We develop techniques to obtain rigorous bounds on the behaviour of random walks on combs. Using these bounds we calculate exactly the spectral dimension of random combs with infinite teeth at random positions or teeth with random but finite length. We also calculate exactly the spectral dimension of some fixed non-translationally invariant combs. We relate the spectral dimension to the critical exponent of the mass of the two-point function for random walks on random combs, and compute mean displacements as a function of walk duration. We prove that the mean first passage time is generally infinite for combs with anomalous spectral dimension.Comment: 42 pages, 4 figure

Modelli digitali 3D per documentare, conoscere ed analizzare l’architettura e la costruzione nel mondo antico: l’esempio della Sala Ottagonale delle Piccole Terme di Villa Adriana

For its unique features and size, the Hadrian’s Villa site has always been the object of studies and investigations. Italian and foreign institutions, as well as research organizations, are working together with the common purpose of understanding and protecting the universally recognized ensemble of buildings and works of art, belonging to the World Heritage List since 1999. Within this interdisciplinary framework, over the past decade, new technologies for digital documentation in the field of cultural heritage have gained more importance with respect to the traditional field of architectural/archaeological surveying. Through expeditious surveying (with no physical contact with the object and different measurement resolutions) several 3D reality-based models were created in the last years, with special regards to the Villa’s pavilions characterized by more complex and daring shapes. The aim was a better understanding of specific problems in those cases where archaeological investigation methods may take advantage of a correct and complete digital surveying of elevations in general and in particular of vaulted spaces, intrados and extrados surfaces. 3D digital models of complex roofing, as shown in the case study of the Small Baths, provide additional advantages concerning the use of finite elements analysis (FEA). Both the digital models (current state of conservation and reconstruction hypothesis) underwent to an accurate stress analysis that enables further achievements for site conservation and management and for ancient constructive and designing techniques

Random walks on graphs: ideas, techniques and results

Random walks on graphs are widely used in all sciences to describe a great variety of phenomena where dynamical random processes are affected by topology. In recent years, relevant mathematical results have been obtained in this field, and new ideas have been introduced, which can be fruitfully extended to different areas and disciplines. Here we aim at giving a brief but comprehensive perspective of these progresses, with a particular emphasis on physical aspects.Comment: LateX file, 34 pages, 13 jpeg figures, Topical Revie

RISC-mediated control of selected chromatin regulators stabilizes ground state pluripotency of mouse embryonic stem cells.

BACKGROUND: Embryonic stem cells are intrinsically unstable and differentiate spontaneously if they are not shielded from external stimuli. Although the nature of such instability is still controversial, growing evidence suggests that protein translation control may play a crucial role. RESULTS: We performed an integrated analysis of RNA and proteins at the transition between naïve embryonic stem cells and cells primed to differentiate. During this transition, mRNAs coding for chromatin regulators are specifically released from translational inhibition mediated by RNA-induced silencing complex (RISC). This suggests that, prior to differentiation, the propensity of embryonic stem cells to change their epigenetic status is hampered by RNA interference. The expression of these chromatin regulators is reinstated following acute inactivation of RISC and it correlates with loss of stemness markers and activation of early cell differentiation markers in treated embryonic stem cells. CONCLUSIONS: We propose that RISC-mediated inhibition of specific sets of chromatin regulators is a primary mechanism for preserving embryonic stem cell pluripotency while inhibiting the onset of embryonic developmental programs.This work was funded by: FIRB RBAP10L8TY (MIUR), Fondazione Roma and PAINCAGE FP7 Collaborative Project number 603191 (RB,MD); Flagship Project InterOmics PB.05 and MIUR-PRIN-2012 (FC); Wellcome Trust Core Grant reference 092096 and Cancer Research UK Grant Reference C6946/A14492 (LP); CRUK-Cambridge Institute Core Grant reference C14303/A17197 (DB)

Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV

The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8  TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum