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Arrival directions of UHECRs after the end of phase 1 of the Pierre Auger Observatory
Get PDFThe Pierre Auger Observatory is the largest and most important hybrid detector designed to investigate the origin and the nature of Ultra High Energy Cosmic Rays. The observatory has been continuously operated since 2004, and
has achieved a total detection exposure of approximately 122000 km2sryr. During over 18 years of research, the Auger Observatory has collected a huge amount of high-quality data, which gave us knowledge about the origin of the most energetic particles ever observed in the universe. This contribution will present the main and most recent results of the arrival direction studies obtained with the Auger phase 1 dataset, i.e., the one before the installation of the upgrade Auger Prime, currently under completion. These include the searches for possible sources from small to
large scale: studies of dipolar and multipolar anisotropies, the search for excesses of the order of the scale of tens of degrees at the highest energies, and the search for
excesses of the order of the angular resolution (∼ 1◦) to look for neutral particles
Quantifying multi-Institution KB-plan prediction models transferability in breast cancer radiotherapy: A step forward toward benchmark
Get PDFTen Institutes (INST1-INST10) of the MIKAPOCo consortium set
their KB plan prediction models of whole breast irradiation (WBI) delivered with tangential fields (TF), by using RapidPlan (Varian Medical System, Inc.) and following the same criteria of contouring and plan model building and validation. DVH prediction bands of organs at risk (heart, ipsilateral lung, contralateral lung and contralateral breast) were exported on 20 new patients from the same Institutes (two patients each). SD of mean predicted DVHs among institutes was assessed as inter-institute variability. The estimated Principal Component (PC1) was con
sidered for transferability models evaluation. Transferability cross-validation was further investigated in detail on a larger population for the model showing the poor
est transferability (ModelINST6) against one of the models with high transferability (ModelINST3). Results show a limited inter-institute variability of plan prediction
models (1.8% for DVH ipsilateral lung) and a satisfactory inter-institute transferability, excepting one institute, confirmed by the extended analyses on a larger cohort of test patients of INST6 (vs. INST3). These achievements pave the way for generating benchmarks for plan prediction in WBI with potentially relevant large-scale applications
Spectral analysis of lava flows: Temporal and physicochemical effects
Get PDFIn a volcanic context, the spectral response of lava flows depends on several endogenous and exogenous factors, like chemical composition, passing of years and weathering. A deeper knowledge about lava properties can be inferred by investigating their spectral response in satellite images. Here, we compare the spectral response of lava in time, physical, and chemical characteristics, inspecting visible to infrared high spatial resolution ESA Sentinel-2 satellite images of different volcanoes. Our results show increasing and decreasing patterns of the lava spectral response as a function of time and physicochemical composition
An improved AISHa ion source for new clinical protocols, nuclear-physics and material experiments
Get PDFHadrontherapy is a well-known clinical practice to treat an increasing number of oncological pathologies, in particular inoperable or radioresistant cancers, when it is essential to minimize the dose absorbed by healthy tissue, as in pediatrics or brain tumors. Due to its unique peculiarities, the ECR ion sources able to pro- duce multiply charged ion beams with low ripple, high stability and reproducibility, are the most suitable choice for medical applications, but also to nuclear physics and material experiments. In the framework of the INSpIRIT project, in collabo- ration with the Centro Nazionale di Adroterapia Oncologica (CNAO), an improved Advanced Ion Source for Hadrontherapy (AISHa) was assembled in Pavia in order to increase the CNAO potential in the field of experimental and industrial research, particle physics, and with the long-term goal of introducing new ionic species into clinical practice such as helium, oxygen and later also iron and lithium useful for bio-spatial research. The key peculiarity and the experimental results of the AISHa ion source will be presented together with an overview of the INSpIRIT project
Plasmonic optical fiber meta-tip for cancer biomarkers detection
Get PDFSensors based on Lab-On-Tip (LOT) technology, where suitably designed nanostructures are integrated onto the end face of an optical fiber, are of strategic importance especially in medicine and clinical diagnostics, where minia- turization and portability are key characteristics. To improve the performance of LOT biosensors, we proposed the integration of the optical fiber with plasmonic Metasurfaces (Optical fiber meta-tip, OFMT), sensibly enhancing the light-matter interaction. Here we report on the remarkable capabilities of plasmonic OFMTs to perform label-free detection of cancer biomarkers with improved performances with respect to state-of-the-art optical fiber senso
Haidinger's brushes: Perceiving the polarization of light via an entoptic phenomenon
Get PDFEntoptic phenomena are visual artifacts arising from the interaction of light with the specific physical structure of the eye. Among the most famous ones, the phenomenon of Haidinger’s brushes consists in the perception of a subtle bow tie in the presence of linearly polarized light, and it is originated by the peculiar spa- tial distribution of dichroic carotenoid molecules forming a sort of embedded radial polarizer in the macula. We have developed a compact versatile optical setup for the psychophysical analysis of the perceptual threshold of this entoptic effect. The tests on a group of 113 healthy individuals under conditions of maximum contrast (blue light) reveal the human capability to perceive an average polarization degree around 16%. The same analysis in white light suggests a polarization sensitivity around 55%. The developed prototype outlines a new platform to train the user in the perception of polarization and can help infer the physiological conditions of macular pigments in the fovea
Foreword
Get PDFThis volume contains 16 papers presented at a conference held in Udine on 25 and 26 November 2022. These papers offer good insight on basic issues in physics education such as: i) the development of educational paths; ii) laboratory activities and their integration into teaching/learning paths; iii) active learning in higher education; iv) teacher education and community building; v) the contribution for teaching/learning activities of the history of physics; vi) informal education and interinstitutional collaboration among schools, museums and universities for the learning of physics. The SIF considers education in physics very important and has always devoted great effort in promoting it. Consequently, the SIF is very grateful to the editor of this volume. The papers here collected will surely encourage who works in the educational system to be always innovative in methodologies and contents
An intuitive introduction to the evolution of physical systems
Get PDFWe outline a unified introduction to the general problem of dynamics intended for a high-school students audience. The attempt consists in circumventing the lack of mathematical knowledge with the use of 1) geometric diagrams, 2) a
discretized version of the equations of motion and 3) a simplified form of computation and analysis of their solutions. The aim is to allow students to approach theoretical features as well as computational aspects of the evolution equations through the use of spreadsheets, a work environment students are usually familiar with and an ideal
tool for an intuitive approach to recursive algorithms. The proposal was presented to an audience composed of students of University courses of Physics teaching and to high-school Science teachers
An approach to research-based design of teaching-learning sequences in the context of physics education: Theoretical frameworks, pedagogical methods, and examples of Data Analysis
Get PDFIn this paper we discuss an example of the research approaches practiced at the University of Palermo Physics Education Research Group (UoP-PERG). Particularly, we discuss the design and development with groups of high
school students of two Teaching-Learning Sequences (TLSs) on surface phenomena in liquids, and the data collection and analysis methods. In the introduction, we briefly discuss the educational reconstruction model, that we use as a theoretical framework for the designing of the TLSs, and a pedagogical methodology that in the last years has gained consensus among educators, i.e., active learning. Some
considerations on active learning pedagogical and cognitive psychology foundations are also made. The main aim of the TLSs is to improve students’ learning of surface phenomena, a topic that is quite relevant in Physics and other scientific and technical fields. We provide a research-based, conceptual scheme of what we mean by “improvement of students’ learning”, and present the TLSs phases, that
are based on the well-known inquiry- and investigation-based learning approaches, that are science-specific applications of the general idea of active learning. Then, we describe some methods we use in our researches to collect and give an example of the data analysis needed to study the progression of student learning, with respect to the conceptual scheme provided, and of some of the results obtained
Real-world phenomena as useful tools in physics teaching
Get PDFDelightful real-world phenomena may capture the attention of students and may trigger their curiosity. The rolling of a food can on a conveyor belt in a grocery store, the observation of the optimal angle in a shotput contest or of
the way a sprinter runs, the appearance of a coloured line on a CD or a DVD under white light, the spectacular dance of sun glints on the shallow waters by the seashore are all phenomena which can be proposed to high-school or undergraduate college students in the “engagement” phase of a lecture in which the Inquiry-Based Learning approach is used. In this work we propose these examples along with a brief justification, based on elementary physics principles, of the observed phenomena