Operational atlas of exposed mortars and conglomerates for interventions on the widespread architectural heritage

When it comes to Science Heritage, the availability of refined investigation techniques, an advanced knowledge of the characteristics of materials, the current technological capacity and the synergy of specialised operators, coordinated into multidisciplinary teams, guarantee, with the support of cutting-edge tools, excellent results for every conservative operation applied to monumental buildings of acknowledged interest. On the contrary, there are still strong limits to the likelihood that this excellence will reverberate on the multitude of interventions performed on widespread architectural heritage. The research project underway envisages the preparation of an operational atlas of reference for exposed mortars and conglomerates, based on the historical and technological knowledge of materials (particularly those available locally) complete with experimental data on constitution and performance, which is useful to support the development of compatible maintenance and conservation procedures

From scan-to-BIM to a structural finite elements model of built heritage for dynamic simulation

The progress in information technology allows an innovative transformation of practices commonly involved in the engineering and construction field, especially in relation to the existing architectural heritage’s control and management activities. The proposed methodology takes advantage of an integrated 3D metric survey as a basis for an HBIM (Historic Building Information Modelling) model to be exploited for the definition of a Finite Elements Model (FEM). This paper aims to show the applicability of a digital process, stemmed from the integration in Rhinoceros 3D of a BIM structural model, leading to the dynamic simulation of the analytical FEM through PRO_SAP® (a PROfessional Structural Analysis Program). The described workflow investigates the interoperability issues, along with the difficulties in the Scan-to-HBIM processes, demonstrating how HBIM models can anyhow support operations aimed at maintaining and preserving existing historical assets, also from a structural point of view, even if with still persistent criticalities

Extended LaSalle's invariance principle for full-range cellular neural networks

In several relevant applications to the solution of signal processing tasks in real time, a cellular neural network (CNN) is required to be convergent, that is, each solution should tend toward some equilibrium point. The paper develops a Lyapunov method, which is based on a generalized version of LaSalle's invariance principle, for studying convergence and stability of the differential inclusions modeling the dynamics of the full-range (FR) model of CNNs. The applicability of the method is demonstrated by obtaining a rigorous proof of convergence for symmetric FR-CNNs. The proof, which is a direct consequence of the fact that a symmetric FR-CNN admits a strict Lyapunov function, is much more simple than the corresponding proof of convergence for symmetric standard CNNs

Digital image correlation applied to lime-based mortars: Shrinkage tests for durability evaluations in restoration works.

Repair mortars applied to architectural heritage buildings for preservation, maintenance, restoration, and strengthening must be carefully studied regarding the many different compatibility issues. In the case of repair interventions, two closely related aspects are especially important: the mortar composition, and the method of its application, which can strongly influence the shrinkage phenomena during the setting and hardening phases. The aim of present experimental research is to set-up a procedure by Digital Imaging Correlation (DIC) technique to deepen shrinkage phenomena in lime-based mortars, thus comparing many different materials, wrongly considered to be similar in behaviour. The technique enable not only shrinkage measurement accuracy higher than standard tests, but also to understand its mechanisms of evolution over time, by evaluating locally strain stress before micro-crack appearing. The interpretation of a large number of test results represents a significant contribution to the development of operational tools to address material selection in specific contexts

Soft gluon resummation of Drell-Yan rapidity distributions: theory and phenomenology

We examine critically the theoretical underpinnings and phenomenological implications of soft gluon (threshold) resummation of rapidity distributions at a hadron collider, taking Drell-Yan production at the Tevatron and the LHC as a reference test case. First, we show that in perturbative QCD soft gluon resummation is necessary whenever the partonic (rather the hadronic) center-of-mass energy is close enough to threshold, and we provide tools to assess when resummation is relevant for a given process. Then, we compare different prescriptions for handling the divergent nature of the series of resummed perturbative corrections, specifically the minimal and Borel prescriptions. We assess the intrinsic ambiguities of resummed results, both due to the asymptotic nature of their perturbative expansion, and to the treatment of subleading terms. Turning to phenomenology, we introduce a fast and accurate method for the implementation of resummation with the minimal and Borel prescriptions using an expansion on a basis of Chebyshev polynomials. We then present results for W and Z production as well as both high- and low-mass dilepton pairs at the LHC, and show that soft gluon resummation effects are generally comparable in size to NNLO corrections, but sometimes affected by substantial ambiguities.Comment: 75 pages, 34 figures, pdflate

Malte e conglomerati a vista: verso un atlante dinamico

The report sets out the main objectives and presents the first specific results of an experimental research on the general theme of mortars and conglomerates for historic and traditional buildings; the work is developed by a research group of the Polytechnic of Turin, and grafted on the results of an experimental research on local aggregates based mortars for historical buildings. The ongoing study will coordinate in particular in-depth studies aimed at the mechanical and performance characterization of innovative materials. One of the main objectives of this line of research is the following: - to define a reference ‘atlas’, compared to many mixtures of mortars and conglomerates, for restoration, recovery, and maintenance of historic buildings, - to encourage (in particular for small yard sites) the use of local materials with a 'short supply chain', compatible and installed with traditional techniques and methods, - to enhance methods of choice oriented towards the circular economy (respecting their values of historical and technological testimony and significant stratifications). The research is also based on experimental data by laboratory tests and by some sites of historic buildings, also with the support of the Superintendence for the architectural heritage of Piedmont and companies producing material

Health technology assessment of pathogen reduction technologies applied to plasma for clinical use

Although existing clinical evidence shows that the transfusion of blood components is becoming increasingly safe, the risk of transmission of known and unknown pathogens, new pathogens or re-emerging pathogens still persists. Pathogen reduction technologies may offer a new approach to increase blood safety. The study is the output of collaboration between the Italian National Blood Centre and the Post-Graduate School of Health Economics and Management, Catholic University of the Sacred Heart, Rome, Italy. A large, multidisciplinary team was created and divided into six groups, each of which addressed one or more HTA domains.Plasma treated with amotosalen + UV light, riboflavin + UV light, methylene blue or a solvent/detergent process was compared to fresh-frozen plasma with regards to current use, technical features, effectiveness, safety, economic and organisational impact, and ethical, social and legal implications. The available evidence is not sufficient to state which of the techniques compared is superior in terms of efficacy, safety and cost-effectiveness. Evidence on efficacy is only available for the solvent/detergent method, which proved to be non-inferior to untreated fresh-frozen plasma in the treatment of a wide range of congenital and acquired bleeding disorders. With regards to safety, the solvent/detergent technique apparently has the most favourable risk-benefit profile. Further research is needed to provide a comprehensive overview of the cost-effectiveness profile of the different pathogen-reduction techniques. The wide heterogeneity of results and the lack of comparative evidence are reasons why more comparative studies need to be performed

Changes in high-intensity precipitation on the northern Apennines (Italy) as revealed by multidisciplinary data over the last 9000 years

Several record-breaking precipitation events have struck the mountainous area of the Emilia-Romagna region (northern Apennines, Italy) over the last 10 years. As a consequence, severe geomorphological processes such as debris avalanches and debris flows, shallow landslides, and over-bank flooding have affected the territory, causing severe damage to human-made structures. The unusual intensity of these phenomena prompted an investigation into their frequency in the past, beyond instrumental time. In the quest for an understanding of whether these phenomena are unprecedented in the region, peat bog and lake deposits were analyzed to infer the frequency of extreme precipitation events that may have occurred in the past. We present the results of a dedicated field campaign performed in summer 2017 at Lake Moo in the northern Apennines, a 0.15 km(2) peat bog located at an altitude of 1130 m a.s.l. During the extreme precipitation event of 13-14 September 2015, several debris flows generated by small streams affected the Lake Moo plain. In such a small drainage basin (<2 km(2)), high-density floods can be triggered only by high-intensity precipitation events. The sedimentary succession (ca. 13 m thick) was studied through the drilling of two cores and one trench. The sequence, characterized by clusters of coarse-grained alluvial deposits interbedded with organic-rich silty clays and peat layers, was analyzed by combining sedimentological, pollen, microanthracological and pedological data with radiocarbon dating (AMS C-14) in an innovative multidisciplinary approach for this area. Original data acquired during the field campaign were also correlated with other specific paleoclimatic proxies available in the literature for the northern Apennines area. We discover that the increase in extreme paleoflooding, associated with coarse-grained deposits similar to the ones observed recently, correlates well with the warm phases of the Holocene Thermal Maximum and with the ongoing warming trend observed that started at the beginning of the last century

Valutazione della vulnerabilità sismica della chiesa di sant’Agostino ad Amatrice tramite analisi multitemporali

La chiesa di Sant’Agostino ad Amatrice è divenuta il simbolo dei tanti beni architettonici gravemente danneggiati dalla lunga sequenza sismica del 2016- 2017, che progressivamente l’ha portata ad un crollo quasi totale. La ricerca multidisciplinare ha avuto la finalità di interpretare il danneggiamento della chiesa, prima in forma di gravi lesioni e poi definitivamente di collasso, correlando in modo interdisciplinare un insieme di dati eterogenei. I modelli digitali derivati dai rilievi 3D realizzati seguendo i progressivi danneggiamenti, gli studi storici delle lesioni emerse in seguito ad altri importanti eventi sismici del passato, lo studio e l’analisi critica dei precedenti lavori di consolidamento, i risultati della microzonazione sismica per la definizione della risposta sismica locale dell’edificio, i risultati delle prove diagnostiche eseguite in situ sulle strutture murarie e la modellazione agli elementi finiti del comportamento dinamico dell’edificio sono discussi in forma integrata

Actigraphic Sensors Describe Stroke Severity in the Acute Phase: Implementing Multi-Parametric Monitoring in Stroke Unit

: Actigraphy is a tool used to describe limb motor activity. Some actigraphic parameters, namely Motor Activity (MA) and Asymmetry Index (AR), correlate with stroke severity. However, a long-lasting actigraphic monitoring was never performed previously. We hypothesized that MA and AR can describe different clinical conditions during the evolution of the acute phase of stroke. We conducted a multicenter study and enrolled 69 stroke patients. NIHSS was assessed every hour and upper limbs' motor activity was continuously recorded. We calculated MA and AR in the first hour after admission, after a significant clinical change (NIHSS ± 4) or at discharge. In a control group of 17 subjects, we calculated MA and AR normative values. We defined the best model to predict clinical status with multiple linear regression and identified actigraphic cut-off values to discriminate minor from major stroke (NIHSS ≥ 5) and NIHSS 5-9 from NIHSS ≥ 10. The AR cut-off value to discriminate between minor and major stroke (namely NIHSS ≥ 5) is 27% (sensitivity = 83%, specificity = 76% (AUC 0.86 p &lt; 0.001), PPV = 89%, NPV = 42%). However, the combination of AR and MA of the non-paretic arm is the best model to predict NIHSS score (R2: 0.482, F: 54.13), discriminating minor from major stroke (sensitivity = 89%, specificity = 82%, PPV = 92%, NPV = 75%). The AR cut-off value of 53% identifies very severe stroke patients (NIHSS ≥ 10) (sensitivity = 82%, specificity = 74% (AUC 0.86 p &lt; 0.001), PPV = 73%, NPV = 82%). Actigraphic parameters can reliably describe the overall severity of stroke patients with motor symptoms, supporting the addition of a wearable actigraphic system to the multi-parametric monitoring in stroke units