Scientific Open-access Literature Archive and Repository
Not a member yet
16397 research outputs found
Sort by
La valorizzazione dei musei locali attraverso Wikipedia: il progetto MedAniene
Get PDFThe aim of this contribution is to explain workflows, methodologies and impact of the MedAniene Project, that was realised through the collaborative use of Wiki platforms and coordinated by the APS ArcheoFOSS. The project involved creating or modifying Wikipedia pages for the museums of the Aniene Valley, uploading images to the Wikimedia Commons repository and structuring relational information in the Wikidata system. The goal of the work was to improve the communication and increase the visibility of those museums by providing the public with open access scientific explanations and implementing data relationships through several heuristic systems which are available to the digital audience. Building such an informative apparatus offers the opportunity to learn about shared digital cultural heritage, increasing awareness in external users and in communities. It is now possible to analyse data on views, accesses and clicks on contents and evaluate the impact of specific activities in terms of audience targeting and engagement. Indeed, this work proposes a methodology for the establishment of a digital, open and collaborative communication space, improving the connection between cultural entities and communities
Reconstruction of Epipaleolithic settlement and climatic refugiain the Zagros Mountains during the Last Glacial Maximum (LGM)
Get PDFThe Iranian Plateau is an important geographical unit located in a key potential region for the Pleistocene population dispersals across Eurasia. Despite its important location and a long history of archaeological investigations, the Epipaleolithic sites distribution pattern and connectivity remained less explored compared to the Middle and Upper Paleolithic periods. In this study we used ecological niche modelling (Generalized Linear Models, Generalized Additive Models, Generalized Boosting Models, Maximum Entropy Modelling and Random Forest), together with corridor mapping methods, to reconstruct the Epipaleolithic settlements and their connectivity in the Zagros Mountains. We showed that the central parts and the western slopes of the Zagros Mountains were the most suitable areas for Epipaleolithic settlement during the Last Glacial Maximum (LGM). Topographic complexity was the most important variable in shaping Epipaleolithic settlement distribution with a positive association. The niche model and corridors maps developed for the Epipaleolithic humans show areas potentially suitable for the presence of Epipaleolithic settlements but no site has been discovered in this area so far. Thus, these areas are having high priority for future field excavations
Food, distance and power. Modeling a multi-factor protoÂhistoric landscape in the Po plain
Get PDFThe paper illustrates the creation and integration of the environment as a multilevel landscape in AMPBV Simulator, a spatial Agent-Based Model (ABM) developed in NetLogo programming language. The model was conceived with the aim of investigating, through a simulative approach, the events and the circumstances (both anthropic and environmental) that presumably led, between the end of the Late Bronze Age, in the 12th cent. BC, and the beginning of the Final Bronze Age, the protohistoric communities of the Southern Verona plain (known as the Northern Terramare polity) from a climatic phase of maximum development and articulation to an anti-climatic phase of sudden collapse. The study context is an interesting application for an investigation through ABM, both because of the complexity of the case scenario, in which several interrelated actors and factors must have played an important role, and because of the availability of a number of geographical and archaeological data providing both a term of comparison and an excellent information base. With the development of an artificial environment and by modeling processes potentially critical for the fate of the Terramare system, the aim is, on the one hand, to give such a complex study case a new tool for historical analysis and, on the other hand, to experiment Agent-Based Modeling and assess its potential as a methodology for archaeological investigation in the Po Plain
A predictive model to investigate the agro-pastoral exploitation of ancient landscapes
Get PDFThanks to the reconstruction of agro-pastoral land use of a territory, it is possible to obtain much information, both of an ecological nature, and about the populations. By the reconstruction of these dimensions of a community it is possible to understand not only the aspects linked to the exploitation of a territory, the subsistence and demography of a given group, but also more generally the group’s social organization itself. With a series of GIS tools, capable of applying the FAO’s land evaluation techniques, it has been possible to generate a predictive raster model of the landscape with the degree of agro-pastoral suitability inside each cell. Thanks to this model, the agro-pastoral exploitation of a territory can be simulated, calculating the food production of each settlement, as well as the consequent demography maximum sustainability. Thanks to the identification of specialized productions sites and of settlements capable of producing a ‘surplus’, or vice versa ‘not-self-sufficient’, it will be possible to articulate socio-political models, hypothesizing exchange networks or relationships between the different sites. The text illustrates in detail the structure and functioning of the developed model, as well as its applications in the archaeological context of the ‘Ager Tarquiniorum’ during the Final Bronze Age
Laser based detection of 14CO2 in radioactive waste
Get PDFA laser based spectroscopic technology, named SCAR (Saturatedabsorption CAvity Ring-down), has been demonstrated for accurate radiocarbon (14C) determination in carbon dioxide. In particular, different materials from nuclear power plants, e.g., concrete and graphite, were burnt and the combustionproduced carbon dioxide was analyzed to asses the amount of 14C, a key species for
nuclear decommissioning. The SCAR technology has demonstrated a performance equivalent or better to AMS and it is ready for further studies and deployment in nuclear waste management areas
Measurements of radioactivity in the environment for radiation protection purposes
Get PDFMeasurements of radioactivity in the environment, according to Article 35 of the Euratom Treaty, are routinely carried out by regulatory bodies and operators in charge. These activities are performed both locally and nationally, in order to assess effective doses to the population. In this context, therefore, it is necessary not only to determine the component due to external irradiation, but also to evaluate the deposit and accumulation of radioactivity in the environment that can reach the public via inhalation or ingestion. The contribution presents a brief description of the aspects regarding programs of monitoring and evaluation of the radioactivity in the environment, in particular the environmental matrices to be monitored, the analyses to be carried out, the related reporting levels as well as the features concerning the influence of the climate on the variations of dose rate values. Finally, a focus on some radiometric measurements performed over the last forty years in the environmental monitoring activities carried out in the ENEA Casaccia Research Center (Rome), in which two nuclear research facilities are currently operating, is presented
Nanosecond dynamics in few-layer and heterojunction transition metal dichalcogenides from liquid phase exfoliation
Get PDFThe lifetimes of photogenerated charge carriers must be long enough to guarantee high efficiency of light harvesting devices. Two-dimensional transition metal dichalcogenides (TMDs) are promising materials due to their intense lightmatter interaction. Liquid phase exfoliation is a low-cost, versatile, scalable method able to produce polydisperse nanosheets in the form of inks. Here, we use nanosecond transient absorption spectroscopy to investigate the charge carrier dynamics in MoS2, WS2, and heterojunctions (HJs) of the two. We observe that the HJ stacking order does not affect the dynamics. We find that in thicker and larger flakes of the single material the carrier lifetime is significantly longer than even in HJs,
due to different electronic contributions from nanosheet basal plane and edges. We conclude that there is no need for additional complexity in stacking two TMDs, and transport properties are enhanced in thicker and larger flakes. Our findings can be exploited for device fabrication
Radiobiological model for β-emitter radiopharmaceutical therapy in dynamic cell cultures in the framework of the ISOLPHARM project
Get PDFIn medical physics and radiobiology, the most common method to probe the efficacy of radiation therapy approaches in vitro is the cell survival trial. Recently, the traditional procedure for external beams has been extended by some
groups to targeted radionuclides. In parallel, the bioengineering state of the art allows for the use of 3D tissue-mimicking scaffolds to obtain realistic cell cultures in dynamic conditions. The aim of this study is to implement a mathematical model for the assessment of β-emitting radiopharmaceuticals, considering their molecular kinetics in vitro and how it affects the radiation delivery to cells. The molecular transitions will be assumed to fulfill the definition of Markov processes, while the cell survival will depend on the DNA damage, in competition with a logistic growth. The solutions of the resulting differential system will be evaluated by means of numerical examples. This work belongs to the framework of the ISOLPHARM project, headed
by INFN-LNL, which has the aim of developing innovative radiopharmaceuticals exploiting the Isotope Separation On-Line (ISOL) at the SPES facility
Magnetic properties of thick synthetic antiferromagnets with different ferromagnetic layers
Get PDFSynthetic antiferromagnets (SAF) are versatile magnetic structures consisting of two ferromagnetic thin films with antiparallel magnetization, separated by a thin non-magnetic spacer. They are used in modern spintronics as building blocks of spintronic devices for data storage applications, computing, and as magnetic-field sensors. More recently, they have been proposed as media for efficient skyrmions and spin-waves propagation, and for spin-torque oscillators.
Tailoring their properties is therefore of fundamental importance for the development of novel nanomaterials. In this work, the magnetic properties of different types of SAFs are investigated via vibrating sample magnetometry, by changing the thickness of the layers. Importantly, while a decrease of the saturation and interlayer exchange coupling field for thicker systems is present, the desired antiferromagnetic coupling at remanence is still robust. These results suggest that by modulating the thickness of the layers, it is possible to finely engineer the SAF magnetic properties even in tens of nm-thick SAFs, enabling a new degree of freedom in the design and development of novel magnetic nanodevices
Studying ultrafast carrier diffusion in spatially heterogeneous samples with transient holographic microscopy
Get PDFTransient absorption microscopy enables the observation of ultra fast excited-state dynamics with spatial resolution. Conventional implementations are technologically limited to small fields of view around a single diffraction-limited
spot, offering no statistical information on the photophysics of the sample. We recently used off-axis holography to demonstrate an all-optical lock-in camera enabling widefield transient imaging at arbitrary repetition rate. Here, we use a structured excitation pattern comprised of hundreds of diffraction-limited spots as an effective way to study diffusion of carriers in semiconductors, whilst probing the sample’s heterogeneity over an area of (≈60μm2), more than 100 times larger than current techniques. We envision that this technique can be used to provide a much more complete picture of photophysical processes in heterogeneous samples