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HERD: The High Energy cosmic-Radiation Detector
No full textAn overview of the High Energy cosmic-Radiation (HERD) detector will be presented, as one of the prominent instruments to be installed onboard the upcoming Chinese Space Station (CSS). Primary scientific goals regarding this initiative include: precise measurements of the cosmic-ray (CR) energy spectra and mass composition, at energies up to the PeV range; contributions to high-energy
gamma-ray astronomy and transient studies; as well as indirect searches for Dark Matter (DM) particles via their annihilation/decay to detectable products. HERD is configured to accept incident particles from both its top and four lateral sides. Specifically considering its initial setup, HERD comprises a homogenous calorimeter,
conceived as an octagonal prism of LYSO cubic crystals, subsequently enclosed by layers of silicon trackers and plastic scintillator detectors, thus finalized with the
instrumentation of a transition radiation detector on one of its lateral faces. In that sense, an order of magnitude increase in acceptance (regarding previous missions) is
foreseen, owing to its pioneering design. Continuous updates and beam tests validate HERD’s capabilities, while varying configurations are tested in order to optimize its
performance
Optical design of the Tor Vergata Synoptic Solar Telescope (TSST)
No full textSynoptic full-disk solar telescopes are fundamental instruments for present and future Solar Physics and Space Weather. They are typically used to study and monitor the solar activity by using high temporal cadence observations
at different wavelengths. The TSST (Tor Vergata Synoptic Solar Telescope) is a new synoptic telescope composed of two spectral channels: an Hα (656.3 nm) telescope and a Magneto-Optical Filter (MOF)-based telescope in the potassium (KI D1) absorption spectral line at 769.9 nm. Hα observations are fundamental for the identification of flaring regions. The MOF-based telescope will produce line of sight magnetograms and dopplergrams of the solar photosphere, which are respectively used to study the magnetic field’s geometry in active regions and dynamics of the solar atmosphere. In this work, we present an overview on the TSST and the optical design and characteristics of the MOF-based telescope, whose optical scheme is a double-Keplerian 80 mm refractor with an aberration-free imaging lens
FLASH Therapy: An innovation in radiation therapy
No full textRadiation Therapy (RT) is nowadays the most common methodology to treat cancer cells. The most important requirement is to destroy the tumor and to minimize the damage of the healthy tissues as well as any side effect. In this scenario, an innovative technique has been proposed and already tested: the FLASH Therapy, which uses short pulses of electrons at very high dose rates. It foresees millisecond pulses of radiation (beam on time 40–300 Gy/s). These bursts of radiation are less harmful to healthy
tissues but just as efficient as conventional treatment to inhibit tumor growth. We will discuss the genesis of this methodology, its implementation based on an electron
linear accelerator and its evolution
Microbubble whispering gallery mode resonator as an all-optical platform for the characterisation of photoacoustics contrast agents
No full textThis article presents a microbubble resonator (MBR) as an alloptical ultrasound transducer specialized for the characterisation of photoacoustics (PA) contrast agents. In the presented proof-of-concept experiment, a well-known
contrast agent (gold nanorods, GNRs) was placed within the MBR and acoustic detection was achieved by monitoring an MBR optical resonance, exploiting the MBR mechanical resonances to enhance the transduction mechanism. The read-out signal from the MBR was validated through a numerical simulation and through the reconstruction of the GNRs photostability trend, proving the feasibility of the
characterisation. This work sets the stage for the application of the MBR system to a specific task, taking advantage of its promising features: sensitive PA detection, extremely small volume, ease of integration in a microfluidic circuit, absence of acoustic matching material and scalability
Dosimetry in Space: The shielding effectiveness for the radioprotection of astronauts against 1 GeV protons
No full textThe study of materials suitable for radiation protection of astronauts in space missions is always a topic of fundamental importance. The main aim of any radiation protection program in space is to minimize the crew’s exposure to ionizing radiation. This work concerns the effectiveness of shielding materials against radiation in space conditions, in particular for the Galactic Cosmic Radiation. The study was conducted by developing a simulation tool based on the Geant4 framework. The physics case reported here deals with the interaction of a 1 GeV
proton beam (protons represent about 87% of the GCR flux with the energy spectrum peak around 1 GeV) with a target added with boric acid or gadolinium (Gd) to deplete neutron escaping. Charge, mass and energy distributions of secondary particles generated by the interaction are computed on the basis of different interaction models. It is found that the particles escaping the shielding material and reaching an ionization chamber located in the opposite side of the shield are still mainly protons and neutrons. The added boric acid acts as an effective neutron mitigating material. However, the average dose does not change effectively because of the additional production of alpha particles from the reaction 10B(n, α)
NATO Science for Peace and Security (SPS) project “BioPhyMeTRE”: “Novel biological and physical methods for triage in radiological and nuclear (R/N) emergencies”
No full textIn case of Radiological and Nuclear (R/N) emergencies, the early knowledge on the individual radiation absorbed dose is of paramount importance for sorting out unaffected subjects from those requiring medical intervention. Retrospective dosimetry by using biological and physical methods aims to prioritize the selection of over-exposed individuals for a rapid triage-dose assessment. In this
context, the BioPhyMeTRE project focuses on the validation of innovative biological and physical methods allowing a rapid screening/triage of potential victims, by using inexpensive and user-friendly analytical procedures and devices. The biological method combines the two most standardized biodosimetry methods into a single one and the physical technique concerns the use of a low-cost, portable mini photo-luminescence reader for the individual dose assessment by using personal objects that civilians wear or carry every day. Next to the experimental work, the project includes training for the transfer of knowledge and skills among the partners, inter-laboratory exercises for the validation of the analytical procedures and disseminations of the results. The preliminary results of these activities are here reported
Geografia delle emozioni primarie e degli atteggiamenti durante il distanziamento sociale ai tempi del covid-19 in Italia
Get PDFThe global health emergency, due to the spread of covid-19, has led Italy and many national governments to uptake containment measures, such as the implementation of nationwide lockdowns. This political response has resulted in a sudden restriction of physical interactions within social, parental and friendship networks, and in the unexpected intensification of proximity among cohabitants. This unprecedented event has paved the way for the study of the psychosocial effects of the lockdown, starting from economic and relational aspects. It also has brought back to light the classical theories of social sciences and, in particular, the importance of concepts such as identity, community and social networks.
The paper describes some of the results of the first survey by the cnr irpps musa-covid-19 Observatory; the analysis, in this case, has been carried out through the use of a multivariate data analysis technique. The results show
that, during the first phase of lockdown, in particular in the Southern regions
of Italy, risks related to job and income have had minor impact on the perception of primary negative emotions rather than the other variables on relational dynamics, such as the family atmosphere
Epigrafia urbana. Comunicazione plurilingue sui muri di Roma (in tempo di COVID)
Get PDFIn Rome street artists were deeply involved in the representation of the Coronavirus pandemic and in the different aspects of the lockdown. They touched and themed several sensitive issues, such as the rules of social distancing and protective devices, the role of healthcare personnel, fake news, the relationship between human beings and nature and animals. They also examined human feelings and emotions, in particular the sense of worry and isolation along with the positive of resilience, solidarity and hope.
The paper presents a selection of the richness of street art in Rome during
the pandemic aiming to identify works by different authors and styles; this research is related to the project cnr Urban epigraphy. Multilingual communication on the walls of Rome
Places of life and death: Spatial distribution and visibility of juvenile residents who were victims of homicide in Porto Alegre (Brazil)
Get PDFThe paper aims to develop a spatial representation of homicides that occurred in Porto Alegre between the years 2015 and 2018. Based on data from the Mortality Information System (SIM), organized by the Municipal Health Department, the paper traces the profile of the victims - regarding age, gender, and race - and analyses the spatial distribution of the homicides in the city. Thus, it was possible to reaffirm the idea that homicides mainly victimize young black males. The age curve demonstrates the increase of victims aged between 15 and 19 years old, which was not a reality a decade ago. Also, the race and gender curves demonstrate a proportional decrease of white victims, and a slight increase in female representation. Finally, regarding the life and death places of the murdered youth, the concentration of events still occurs in the Rubem Berta, Restinga, Santa Tereza, Sarandi, and Lomba do Pinheiro neighborhoods
Long-term Positivity to SARS-CoV-2: A Clinical Case of COVID-19 with Persistent Evidence of Infection
Get PDFIn December 2019, an outbreak of a new coronavirus (SARS-CoV-2) was reported in Hubei province in China. The disease has since spread worldwide and the World Health Organization declared it a pandemic on 11 March 2020. We describe the case of a 65-year-old woman who clinically recovered from COVID-19 but showed persistent infection with SARS-CoV-2 for 51 days