L'importanza di un approccio multidisciplinare coordinato nelle indagini sui monumenti dell'antichità

An in-depth preliminary knowledge of a cultural heritage is necessary to protect and preserve the cultural heritage itself. For this purpose, today we can use a lot of methodologies developed by scholars of different disciplines: archaeologists, historians of Art, architects, engineers, biologists, chemists, physicists. Also two other new disciplines, Archaeoastronomy and Analysis of the geometries, can complete and integrate this knowledge. This work collects the results of the investigation on geometrical and numerical schemes and associated length units and on orientation and astronomical meaning of some artefact belonging to different eras: the hypogeal Neo-Pytagorean Basilica at Porta Maggiore in Roma and the Mithraea in Ostia Antica

The orientation of the Mithraea in Ostia Antica

We conducted an investigation on the orientations and geometrical content of the Mithraea of Ostia Antica. A geometrical CAD study based on the most reliable plans from the Archives of the Sovrintendenza Speciale per il Colosseo, il MNR e l’Area Archeologica di Roma – Ostia Antica, aside with the identification of geometrical and numerical schemes and associated length units, allowed us to identify the axes of the Mithraea. Then the orientations of the axes were measured on field by means of a professional compass with ± 0.5° uncertainty. The distribution of these measured azimuths follows the topography of the city. On the contrary, the Decumanus, the main street of the town, presents an indubitable orientation toward the Winter Solstice Sunset. This was ascertained by measuring the coordinates of four significant points along the street with the help of a palmar Trimble GPS which averages 100 measures per point. The exceptional density of Mithraea in Ostia led us to suppose that a symbolic cosmic-solar value is to be searched in the orientation as a whole of the town itself, founded half a millennium before the first presence of Mithraism in Rome. The Decumanus could be considered the very holder of this symbolic value with its orientation toward the Winter Solstice Sunset, possibly making of Ostia a very special place for Mithraicism

A New Fast Silicon Photomultiplier Photometer

The realization of low-cost instruments with high technical performance is a goal which deserves some efforts in an epoch of fast technological developments: indeed such instruments can be easily reproduced and therefore allow to open new research programs in several Observatories. We realized a fast optical photometer based on the SiPM technology, using commercially available modules. Using low-cost components we have developed a custom electronic chain to extract the signal produced by a commercial MPPC module produced by Hamamatsu, in order to obtain sub millisecond sampling of the light curve of astronomical sources, typically pulsars. In the early February 2011 we observed the Crab Pulsar at the Cassini telescope with our prototype photometer, deriving its period, power spectrum and shape of its light curve in very good agreement with the results obtained in the past with other instruments.Comment: Accepted for Publications of the Astronomical Society of Pacific (PASP), 8 pages, 8 figure

SiFAP: A New Fast Astronomical Photometer

A fast photometer based on SiPM technology was developed and tested at the University of Rome "La Sapienza" and at the Bologna Observatory. In this paper we present the improvements applied to our instrument, concerning new cooled sensors, a new version of the electronics and an upgraded control timing software

SiFAP: A New Fast Astronomical Photometer

A fast photometer based on SiPM technology was developed and tested at the University of Rome "La Sapienza" and at the Bologna Observatory. In this paper we present the improvements applied to our instrument, concerning new cooled sensors, a new version of the electronics and an upgraded control timing software

Sensitivity and specificity of in vivo COVID-19 screening by detection dogs: Results of the C19-Screendog multicenter study

Trained dogs can recognize the volatile organic compounds contained in biological samples of patients with COVID-19 infection. We assessed the sensitivity and specificity of in vivo SARS-CoV- 2 screening by trained dogs. We recruited five dog-handler dyads. In the operant conditioning phase, the dogs were taught to distinguish between positive and negative sweat samples collected from volunteers’ underarms in polymeric tubes. The conditioning was validated by tests involving 16 positive and 48 negative samples held or worn in such a way that the samples were invisible to the dog and handler. In the screening phase the dogs were led by their handlers to a drive-through facility for in vivo screening of volunteers who had just received a nasopharyngeal swab from nursing staff. Each volunteer who had already swabbed was subsequently tested by two dogs, whose responses were recorded as positive, negative, or inconclusive. The dogs’ behavior was constantly monitored for attentiveness and wellbeing. All the dogs passed the conditioning phase, their responses showing a sensitivity of 83-100% and a specificity of 94-100%. The in vivo screening phase involved 1251 subjects, of whom 205 had a COVID-19 positive swab and two dogs per each subject to be screened. Screeningsensitivity and specificity were respectively 91.6-97.6% and 96.3-100% when only one dog was involved, whereas combined screening by two dogs provided a higher sensitivity. Dog wellbeing was also analysed: monitoring of stress and fatigue suggested that the screening activity did not adversely impact the dogs’ wellbeing. This work, by screening a large number of subjects, strengthen recent findings that trained dogs can discriminate between COVID-19 infected and healthy human subjects and introduce two novel research aspects: i) assessement of signs of fatigue and stress in dogs during training and testing, and ii) combining screening by two dogs to improve detection sensitivity and specificity. Using some precautions to reduce the risk of infection and spillover, in vivo COVID-19 screening by a dog-handler dyad can be suitable to quickly screen large numbers of people: it is rapid, non- invasiveand economical, since it does not involve actual sampling, lab resources or waste management, and is suitable to screen large numbers of people

New bright carbon stars found in the DFBS

Carbon-rich stars (C stars) of Population II, such as CH giants, can provide direct information on the role of low-to-intermediate-mass stars of the Halo in early Galactic evolution. Moreover, accurate knowledge of the CH stellar population is a critical requirement for building up scenarios for early Galactic chemical evolution

OXYGEN AND CARBON RICH COOL STARS IN THE CEPHEUS REGION: CLASSIFICATION OF SELECTED OBJECTS FROM KP2001 CATALOGUE. I

We present moderate resolution CCD spectra and R photometry for seven KP2001 stars. We revised the spectral classification of the stars in the range lambda lambda 4000-8700 angstrom. Our photometric data confirmed the behavior of the light curves downloaded from the NSVS (Northern Sky Variability Survey) database. For KP2001-32, presented as a Mira-type variable in NSVS, we estimated absolute bolometric M(b) and K-band M(K) magnitudes as well as the distance using the period-luminosity relations. We also estimated the mass loss rate using the calibration relations between mass loss rate and K - [12] index. From the position in infrared color-color diagrams, we confirmed the photometric classification of KP2001-221 as a semiregular variable, based on the light curve of the NSVS database. For the N-type carbon star KP2001-77 we estimated distance and absolute magnitude M(K) using different calibration methods. For the remaining four objects we derived the absolute magnitudes and distances using our CCD spectra and published JHK(S) magnitudes. We discuss the nature of these objects on the basis of the obtained results

The Latest Version of SiFAP: Beyond Microsecond Time Scale Photometry of Variable Objects

Technical improvements of the Silicon Fast optical Astronomical Photometer (SiFAP) allow the instrumentation to integrate photons coming from the target in time windows down to 20μs. Further hardware improvement has been implemented to tag the Time of Arrival (ToA) of each single photon. In addition, a new commercial GPS unit has replaced the older commercial unit improving time resolution. The latest version of SiFAP has been calibrated to check photometric sensitivity and linearity through observations of several standard stars. SiFAP has been also successfully tested by observing the HZ/Her X-1 Binary System estimating the spin period of the pulsar (Her X-1). Our results have been then compared to data available in literature