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Emdb: yet another db for the stratigraphic record
Get PDFThe collection of stratigraphic data has been done for years with offline tools like the Microsoft Access software, which was considered a user-friendly tool with the ability to print standardised context sheets (like the Italian ministerial US sheets) directly and without the need for technical expertise. It is well known to the scientific community the limitation inherent in this type of approach: the data is not shared online and is not easy to be collaboratively edited; the data is locked within a proprietary format with repercussions on medium- to long-term preservation; and it is not immediately possible to integrate the data with other projects due to a lack of precise reference standard. Despite these issues, the offline approach remained viable in a whole range of situations where it is necessary to have a fast and easy-to-manage database. This contribution starts from the hypothesis that an offline standardised and encapsulated tool in an open format (such as SQLite, LibreOffice Base or MySQL), editable with open source software, can offer additional solution because it is easy to use and disseminate in the form of a free, downloadable template. EMdb aims to collect and manage not only stratigraphic data but also reconstructive unit sheets to cover the need to analyse, interpret and validate scientific hypotheses in the field
Balancing between biases and interpretation. A predictive model of prehistoric Scania, Sweden
Get PDFSouthern Sweden, and especially the area around Malmo in southwestern Scania, is perhaps one of the most archaeologically investigated areas in the world. Our knowledge of the local Prehistory has greatly increased in the past decades although it is also the product of centuries of agricultural practices, urban expansion and a relatively early (18th-19th c.) interest for prehistoric monuments (e.g. burial mounds and megaliths). However, despite the deluging amount of available information (over 50,000 ancient sites recorded in Scania), their distribution is not homogeneous and archaeologists are restlessly trying to explain this pattern and its underlying causes. In addition, post-depositional factors (infrastructure works, agricultural practices, etc.) heavily affect site distribution and preservation, blurring the global interpretation. The aim of this paper is to reduce the impact of post-depositional factors on our interpretations on site distribution. In addition, the results can be used as a starting point for further and more elaborate analyses (spatial statistics and simulations). All the models presented here were computed in a reproducible way, relying on FOSS and open data only, in order to allow anyone interested to replicate the model and adapt it to their own purposes and study regions
From legacy data to survey planning? The relationship between landscape and waterscape in Southern Tuscany during the Upper Palaeolithic: towards a predicitive-postdictive approach
Get PDFDuring the Upper Palaeolithic, Southern Tuscany was strongly affected by geomorphological changes that significantly altered its coastal seaboard. In particular, during the Last Glacial Maximum, the sea reached a level below 100 meters. As a result of this, the prehistoric coastland included also the present Tuscan Archipelago, in particular the Islands of Elba and Pianosa, assuming a different layout during MIS3 and MIS2. In this context, the process of prehistoric occupation took place, according to different needs and criteria. The present work explores the possibility of investigating the dynamic relationship between the prehistoric landscape and waterscape by a predictive-postdictive approach. Alongside the simulation of coastal changes, the study makes use of legacy data, taking into account those derived from artefact surface scatters collected over the past decades by various research groups. The latter provide further evidence of the prehistoric occupation process. In this scenario it is crucial to highlight areas that potentially still retain some relict features of the Palaeolithic landscape. These are examined in order to better understand settlement strategies taking place during the Upper Palaeolithic and, at the same time, to investigate the relationship between inland and coastal sites in a diachronic perspective. Although still ongoing, preliminary results provide new elements for the planning of future field surveys
Calibration of XENON1T with 37Ar diffused inside the detector
Get PDFThe XENON project, located at INFN Laboratori Nazionali del
Gran Sasso, aims to directly detect dark matter particles, through the interaction with xenon atoms inside a dual-phase Time Projection Chamber. At the end of the last XENON1T science run, in 2018, a low-energy calibration with an internal 37Ar source was performed for the first time. 37Ar decays by electron capture, with 35-days half-life, emitting photons and electrons which generate two mono energetic signals, at 2.82keV (K-shell) and 0.27keV (L-shell). The final results of the calibration confirm that the behaviour of the detector is well-understood. Additionally, it was proven that cryogenic distillation efficiently removed 37Ar and, therefore, this source can be used for calibrations in multi-tonne xenon detectors
Study of the spatiotemporal learning of dynamic positron emission tomography data for the improvement of diagnostic accuracy in breast cancer
Get PDFThis article is based on the talk delivered on 12 September 2022, in the Medical Physics section of the 108th National Congress of the Italian Physical Society (Milan). This work addresses the challenge of improving PET diagnostic accuracy through an alternative approach based on the analysis of time signal intensity patterns extracted from dynamic PET tissue time activity curves with a deep learning model. Our framework outperforms the discriminative potential of the
classical SUV analysis, paving the way for more accurate dynamic PET-based lesion discrimination without additional acquisition time or invasive procedures. The full study has been published in IEEE Trans. Radiat. Plasma Med. Sci., 7 (2023) 630, with the title Spatiotemporal learning of dynamic positron emission tomography data improves diagnostic accuracy in breast cancer
Visual performance with an extended depth of focus contact lens for myopia control and corneal topography in assessing lens centration
Get PDFIncreasing in myopia prevalence worldwide led to develop control strategies to slow down myopia progression. One option is represented by extended depth of focus (EDOF) contact lens (CL) to control retinal defocus. Decentration in EDOF CLs can decrease the quality of vision. This study was carried out to evaluate accuracy and repeatability of the centration assessment of EDOF CLs using corneal topography; data in term of visual performance with EDOF CLs were also collected. For each EDOF CL, a topography over the CL and a slit lamp (SL) digital picture were taken. For the SL images, a software was used to assess the position of the lens; for the topography acquisitions, the position was detected using a qualitative procedure, by two observers and repeated after 15 days. Visual acuity (VA), was evaluated at high contrast. After the analysis, the accuracy of the topographical assessment with respect to SL assessment resulted good. Intra- and inter-observer reliability of the measurement were good, but the clinical experience of the observer affected the repeatability of the method. VA with EDOF CLs was significantly lower compared to spectacles
The discovery of some articles of Italian physicists in a journal directed in 1948 by Giovanni Polvani
Get PDFIn the period after the Second World War, Giovanni Polvani directed a journal entitled IL FILOMATE. Rivista di Scienze matematiche, Fisiche e Natu- rali, which was published exclusively in 1948 for only a few issues by Dott. Carlo Marzorati publishing house in Milan. Inside this journal, it was possible to find some papers written by the following Italian physicists: Giovanni Polvani himself, Giuseppe Cocconi, Vanna Tongiorgi, Nello Carrara, Carlo Salvetti, Luigi Puccianti, Bruno Ferretti, Augusto Occhialini, and Giorgio Valle. These papers dealt with various physics subjects such as, among others, cosmic rays, radar, and electrical conduction in gases
Alfabeto fotografico
Get PDFThe contribution presents the photographic alphabet made up of 21 photographs taken by Vittorio Tulli in Ny-Ålesund with commentary and captions by anthropologist Paola Atzeni. The alphabet is part of the traveling exhibition “4,404 km: Soil and Subsoil”, which has the metaphor of the voyage of discovery as a common thread. Beginning with a glimpse into the depths and darkness, then moving towards the horizons of knowledge, represented by the North Pole, the exhibition explores the possibilities and limits of knowledge
Tuning electronic and magnetic properties of ultrathin and bulk magnetic oxides by adsorption of organic molecules
Get PDFBy using the Hubbard-corrected density functional theory (DFT+U), we investigate the surface of bulk transition metal monooxides, studying the interaction with adsorbed molecules with/without intrinsic magnetic charac ter. For the paradigmatic case of pentacene/NiO(001), we see that interaction only moderately affects the surface ground state magnetization. Conversely, ultrathin magnetic layers appear controllable by the adsorption of an organic layer, as we see by our DFT investigation for the interface formed by a C60 molecular layer on a two-dimensional Cr4O5 layer supported on Fe(001). There, the local hybridization
between the electronic states of C60 and Cr4O5 is able to modify the magnetic coupling of the Cr atoms: molecules turn the ferromagnetic intra-layer coupling into an antiferromagnetic one; further patterning of the substrate spin polarization can be achieved by controlling the molecular adsorption site
Dielectric multilayers for broadband optical rotation enhancement
Get PDFWedesign a simple dielectric multilayer capable of sustaining broadband superchiral surface waves. We show that the platform can produce large optical chirality enhancements in a wavelength range of hundreds of nanometers. We finally demonstrate that these properties result in the enhancement of the optical rotation signal well above two orders of magnitude, thus extending surface-enhanced chiral
spectroscopies beyond the traditionally addressed circular dichroism signals