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The Experiment to Study Thunderstorm High-Energy Radiation (ESTHER) is a small project of the Italian National Institute for Astrophysics (INAF), devoted to the study of high-energy emissions from thunderstorms, such as Terrestrial Gamma-ray Flashes and gamma-ray glows, which will start in 2024. In order to reduce the absorption typically undergone by gamma-ray radiation in the lower layers of the atmosphere and make these events detectable on the ground, the ESTHER set-up will be installed at high altitudes on Mt. Etna (Italy). We carried out a detailed analysis of lightning occurrence in this geographic region in order to test how suitable such a location is for the installation of a detection system to investigate thunderstorms and related emissions. The analysis pointed out a strong clustering of lightning in the proximity of the mountain peak and over the main volcano craters, where the frequent presence of volcanic ashes could increase, under the conditions of humid air typical of thunderstorms, electrical conductivity. An estimate of the gamma-ray absorption in the air undergone by typical TGF radiation allowed us to evaluate the suitability of two possible installation sites suggested for the project. This study represents a preliminary work for ESTHER and serves as a launching pad for future analyses. [ABSTRACT FROM AUTHOR]

Îł -ray astronomy in the energy range from MeV to GeV can provide a unique detection window for Îł -ray bursts and other transient sources, fundamental information on particle acceleration mechanisms, MeV-blazar population studies up to z ∼ 4.5, and a full overview of line emission from cosmic-ray interaction. Silicon-based pair tracking telescopes rely on Îł -ray conversion into an electronâ€"positron pair and its tracking using a stack of silicon strips. The method presented in this work is based on a Rauchâ€"Tungâ€"Striebel smoother. Its internal Kalman filter enables keeping multiple hypotheses about particle tracks and implementing statistically meaningful measurement selection among hits on different planes of the tracker. The algorithm can be easily configured to work with different tracker geometries and mass models. It can be used for the exploitation of data from past and current Îł -ray missions as well as to assess the performances of new pair-tracking telescopes. The proposed method has been validated on Astrorivelatore Gamma a Immagini Leggero data and then used to investigate the performances of both e-ASTROGAM and All-Sky-ASTROGAM telescopes. The algorithm efficiency and its accuracy in estimating both the photon direction and energy were evaluated on Îł -ray events simulated at different energies in the range between 30 MeV and 3 GeV. The point-spread function of each tracker was then compared with its angular resolution limit showing both the expected performances of the instrument and the margin of improvement that could be obtained by optimizing the reconstruction method. [ABSTRACT FROM AUTHOR]

AGILE is a space mission of the Italian Space Agency dedicated to X-ray and gamma-ray astrophysics operating since 2007. Since the discovery of gravitational wave (GW) events by the LIGO-Virgo Collaboration (LVC) announced in February 2016, AGILE is playing a very important role in the search for possible X-ray and gamma-ray counterparts. The large fields of view of the gamma-ray and hard X-ray imagers (2.5 sr and 1 sr, respectively) and the current spinning mode allow AGILE to cover at any moment a very large fraction of the sky. We present here an overview of AGILE observations of GW events during the LVC observing periods O1 and O2 which span the time interval September 2015–August 2017. In particular, we focus on the main characteristics of AGILE observations of the events GW150914, GW170104, and GW170817. The latter event is of great relevance being associated with a "kilonova" counterpart: we establish important physical constraints on the possible γ -ray emission from a magnetar-like remnant in the first ∼ 1000 s following the GW event time. We also present further developments and preliminary results obtained in preparation of the O3 observing run (start in April 2019). AGILE is fully operative in the search for GW event counterparts, and continues to observe the sky in a unique way because of its combination of large field-of-view hard X-ray and gamma-ray detectors. [ABSTRACT FROM AUTHOR]

In this work, a signal-extraction algorithm pertaining to the Cherenkov Telescope Array's real-time-analysis pipeline has been parallelised using SSE, POSIX Threads and CUDA. Because of the observatory's constraints, the online analysis has to be conducted on site, on hardware located at the telescopes, and compels a search for efficient computing solutions to handle the huge amount of measured data. This work is framed in a series of studies which benchmark several algorithms of the real-time-analysis pipeline on different architectures to gain an insight into the suitability and performance of each platform. [ABSTRACT FROM AUTHOR]

We present a novel open-source 3D-printable dexterous anthropomorphic robotic hand specifically designed to reproduce Sign Languages' hand poses for deaf and deafblind users. We improved the InMoov hand, enhancing dexterity by adding abduction/adduction degrees of freedom of three fingers (thumb, index and middle fingers) and a three-degrees-of-freedom parallel spherical joint wrist. A systematic kinematic analysis is provided. The proposed robotic hand is validated in the framework of the PARLOMA project. PARLOMA aims at developing a telecommunication system for deaf-blind people, enabling remote transmission of signs from tactile Sign Languages. Both hardware and software are provided online to promote further improvements from the community. [ABSTRACT FROM AUTHOR]

Background: Phytoplasmas are bacterial plant pathogens (class Mollicutes), transmitted by phloem feeding leafhoppers, planthoppers and psyllids in a persistent/propagative manner. Transmission of phytoplasmas is under the control of behavioral, environmental and geographical factors, but molecular interactions between membrane proteins of phytoplasma and vectors may also be involved. The aim of the work was to provide experimental evidence that in vivo interaction between phytoplasma antigenic membrane protein (Amp) and vector proteins has a role in the transmission process. In doing so, we also investigated the topology of the interaction at the gut epithelium and at the salivary glands, the two barriers encountered by the phytoplasma during vector colonization. Methods: Experiments were performed on the 'Candidatus Phytoplasma asteris' chrysanthemum yellows strain (CYP), and the two leafhopper vectors Macrosteles quadripunctulatus Kirschbaum and Euscelidius variegatus Kirschbaum. To specifically address the interaction of CYP Amp at the gut epithelium barrier, insects were artificially fed with media containing either the recombinant phytoplasma protein Amp, or the antibody (A416) or both, and transmission, acquisition and inoculation efficiencies were measured. An abdominal microinjection protocol was employed to specifically address the interaction of CYP Amp at the salivary gland barrier. Phytoplasma suspension was added with Amp or A416 or both, injected into healthy E. variegatus adults and then infection and inoculation efficiencies were measured. An internalization assay was developed, consisting of dissected salivary glands from healthy E. variegatus exposed to phytoplasma suspension alone or together with A416 antibody. The organs were then either observed in confocal microscopy or subjected to DNA extraction and phytoplasma quantification by qPCR, to visualize and quantify possible differences among treatments in localization/presence/number of CYP cells. Results: Artificial feeding and abdominal microinjection protocols were developed to address the two barriers separately. The in vivo interactions between Amp of 'Candidatus Phytoplasma asteris' Chrysanthemum yellows strain (CYP) and vector proteins were studied by evaluating their effects on phytoplasma transmission by Euscelidius variegatus and Macrosteles quadripunctulatus leafhoppers. An internalization assay was developed, consisting of dissected salivary glands from healthy E. variegatus exposed to phytoplasma suspension alone or together with anti- Amp antibody. To visualize possible differences among treatments in localization/presence of CYP cells, the organs were observed in confocal microscopy. Pre-feeding of E. variegatus and M. quadripunctulatus on anti-Amp antibody resulted in a significant decrease of acquisition efficiencies in both species. Inoculation efficiency of microinjected E. variegatus with CYP suspension and anti-Amp antibody was significantly reduced compared to that of the control with phytoplasma suspension only. The possibility that this was due to reduced infection efficiency or antibody-mediated inhibition of phytoplasma multiplication was ruled out. These results provided the first indirect proof of the role of Amp in the transmission process. Conclusion: Protocols were developed to assess the in vivo role of the phytoplasma native major antigenic membrane protein in two phases of the vector transmission process: movement through the midgut epithelium and colonization of the salivary glands. These methods will be useful also to characterize other phytoplasma-vector combinations. Results indicated for the first time that native CYP Amp is involved in vivo in specific crossing of the gut epithelium and salivary gland colonization during early phases of vector infection. [ABSTRACT FROM AUTHOR]