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Study on the homogeneity of large-size LYSO:Ce crystals for the HEPD-02 electromagnetic calorimeter
Get PDFLYSO:Ce crystals are known for their high light output, good
energy resolution, compact size and radiation hardness, making them ideal for high-energy physics experiments and medical imaging. These properties also make LYSO:Ce crystals suitable for space-based astroparticle physics experiments. Therefore, the LIMADOU collaboration selected this material to develop a compact electromagnetic calorimeter with 9 LYSO:Ce crystals of 5 × 5 × 4cm3 for the High Energy Physics Detector HEPD-01 mounted on the CSES satellite about 5 five years ago. Now, a second payload HEPD-02 is being constructed with 6 LYSO:Ce samples of 15×5×2.5cm3 fabricated by Filar OptoMaterials, enabling the development of a calorimeter with LYSO:Ce crystals two times larger in volume than the previous one. Since the growing process of crystals of this size requires new techniques for the company, an extensive experimental campaign is necessary to determine the properties of the samples. To this end, the INFN-TIFPA group, involved in the LIMADOU collaboration, has conducted a thorough study of 16 crystals. This paper summarises the main results of this characterization
The NUSES space mission
Get PDFNUSES is a pathfinder project for innovative satellite-borne particle detectors dedicated to the study of cosmic radiation, astrophysical neutrinos, Sun-Earth environment, space weather and magnetosphere-ionosphere-lithosphere
coupling. The satellite will host two payloads, named ZIR´ E and TERZINA. The ZIR´ E instrument will measure the fluxes of low-energy cosmic-ray protons, light nuclei, electrons, positrons and gamma rays with energies up to a few hundreds of MeV. TERZINA will test innovative techniques for the detection of astrophysical neutrino signals, looking at the Cherenkov light produced by the extensive air showers generated in the atmosphere. In the following, scientific objectives and features of the NUSES project will be presented
Elucidating efflux inhibition and avoidance in Pseudomonas aeruginosa
Get PDFAntibiotic resistance is a major threat to public health. Gramnegative pathogens, such as Pseudomonas aeruginosa, are of particular concern. One of the first bacterial defence mechanisms is the active export of drugs out of the cell, mainly mediated by resistance-nodulation-division (RND) efflux pumps. The major RND efflux pump of P. aeruginosa is MexAB-OprM, in which the inner membrane transporter MexB is responsible for the recognition and binding of compounds. Due to the difficulty of producing co-crystals,computational methods are crucial to gaining insights into the interactions between compounds and MexB. We exploited multi-copy molecular dynamics simulations to investigate the binding of peptidomimetics compounds to MexB. Based on microbiology studies, this series was shown to include efflux substrates, inhibitors, and avoiders. The detailed analysis of protein-ligand interactions (both direct and water-mediated) revealed characteristic patterns for each class of compounds, highlighting significant differences. Our results outline molecular-level information that could help the rational design of new inhibitors and new antibiotics less susceptible to the efflux mechanism
Intracavity intensity noise suppression in the inverse Compton scattering source BriXSinO exploiting carrier-envelope offset manipulation
Get PDFWe report on a technique that exploits the control of the carrier- envelope offset to suppress the frequency-to-intensity noise conversion in the lock- ing of a mode-locking laser against a high-finesse optical enhancement resonator. A proper combination of the laser carrier-envelope offset and the resonator finesse allows the improvement of the signal-to-noise ratio of the optical intensity trapped into the optical resonator. In this paper, we show the application of this technique in the laser system of the inverse Compton scattering source BriXSinO, currently under development in Milan, Italy, demonstrating the possibility of achieving an intracavity intensity noise reduction of a factor of 20
The effects of reiterated cell photo-stimulation with an azobenzene
Get PDFOptical stimulation of living cells is an innovative and success- ful tool, having a significant impact on neuroscience. A recently synthesized am- phiphilic azobenzene, named Ziapin2, has been developed exploiting a non-covalent approach for targeting the membrane and achieving cell photostimulation. Here, we investigate, using both experimental data and mathematical modelling, the effect of repetitive light stimulation on the cell response. We discuss some possible explana- tions for the drop in the stimulation efficiency in reiterated stimulation processes
Teleoptometry: State of the art and future perspectives
Get PDFTeleoptometry is a branch of telehealth that makes it possible to provide optometric assistance even when the operator and patient cannot meet in person. It became dramatically popular throughout the Covid-19 pandemic. In the last years, several online platforms have been proposed, expanding what op- tometrists can do remotely. Important areas of future developing of teleoptometry are capture and archive images to be shared with other eye care practitioners for further reference and follow-up via virtual meetings or dedicated apps. Teleoptom- etry is likely to continue to expand its role not only for the management of ocular diseases in rural areas, but also for comprehensive eye examinations. We feel that teleoptometry can be a valuable support of customary in-person services, still we definitely expect that it cannot replace them
Peer learning in higher education: An example of practices
Get PDFNowadays, academic institutions face the challenges of an increas- ing number of student enrolments as well as dropouts. An important factor which allows predicting learner dropout is the number of university educational credits gained across the first term in the first academic year. Since active methods en- hance students’ learning more than traditional lectures, a possible effect of their implementation in an academic course might be an increase in the pass rate in final examinations, thus contributing to moderate the learners’ dropouts. In this perspec- tive, a case study was implemented to examine whether integrating peer learning into traditional physics lectures through the use of technology may have positive effects on student learning in large size classes. This study aimed at 1) outlining how this educational method was implemented in the context of an academic physics course at Politecnico di Milano, and 2) illustrating some preliminary results regarding the final achievement of the students involved in this teaching methodology
History teaches: Some educational projects based on the history of physics
Get PDFWe present some projects carried out in recent years and aimed at students of different levels (from high school to university), where we have adopted well-defined historical paths. The basic aim is to allow the students involved to develop appropriate physical reasoning skills, without the preventive request of a good standard preparation of the topics covered. The lines of action which were common to the various projects were intended to encourage the students to: 1) think like the given scientist of the past who is the object of the project, building step by step proper knowledge and reasoning; 2) work like that scientist, performing the original experiments; 3) deduce just as that scientist did concerning the subject matter; 4) present the results of their activity (including Physics demonstrations) to other students and, in general, to the general public, in order to test their ability to communicate what they have learned and discovered. These educational goals have always been accompanied by the desire to carry out historically consistent activities, based on the awareness of the key role that the history of physics can play in promoting scientific understanding at a deep level, even without requiring particular mathematical knowledge or advanced preparation. The enthusiasm of the students involved in the various projects, especially in demonstrating the result of their work to other students or in public events, as well as the prompt involvement of the aforementioned public (lacking adequate preparation or specific knowledge in the proposed activity), undoubtedly testify in favor of the success of the work presented here
Criminalità e cyberspazio, alcune riflessioni in materia di cybercriminalità
Get PDFLo sviluppo tecnologico avvenuto negli ultimi anni ha trasformato la società in uno “spazio iperconnesso” determinando terreno fertile per la proliferazione di nuove forme di criminalità. In questo articolo si vogliono delineare gli aspetti salienti della criminalità nel cyberspazio attraverso un approccio socio-criminologico con un’analisi del quadro teorico di riferimento ed uno sguardo alla normativa nazionale ed europea. Saranno poi presentate alcune riflessioni in merito agli attori coinvolti in questi nuovi scenari, evidenziando la necessità di dover elevare gli standard di sicurezza e di scambio informativo ma anche di consapevolezza e conoscenza degli strumenti e delle tecnologie da parte di chi quotidianamente ne fa largo utilizzo
The Harris Matrix Data Package specification and the new init command of the Python hmdp tool
Get PDFThis paper presents an update to an earlier proposal for a standardized open format for archaeological stratigraphy data, the Harris Matrix Data Package, and the accompanying software tool implementation. The update is two-fold: firstly, it aims at a clear separation between data format and the software tool, particularly by defining the data format in more detail and independently from the software used to create or analyze it; secondly, it introduces a new software feature that allows the creation of a new data package from scratch. A third issue that was identified is the lack of tools for converting existing data to and from the Harris Matrix Data Package, but this issue is not dealt with in this paper