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Tecniche di preparazione istologica di tessuti gonadici e analisi microscopica per la determinazione dello stato di maturità di Engraulis encrasicolus
Get PDFL’ecologia riproduttiva dei pesci, in particolare il potenziale riproduttivo, è determinante per capire la dinamica di popolazione e ai fini dello stock assessment. La politica per la pesca dell’Unione Europea richiede di assicurare uno sfruttamento delle risorse acquatiche viventi realizzato in modo tale da garantire condizioni di sostenibilità dal punto di vista economico, sociale e ambientale. Il monitoraggio delle risorse marine (ex L.41/82, Regolamento 2008/199/CE, L.R. n.66/05) prosegue da più di 30 anni ed è di supporto alla formulazione dei piani gestionali della pesca e dell’acquacoltura, in un’ottica di riduzione degli impatti ambientali e di sostenibilità delle risorse.
L’uso congiunto di informazioni provenienti da statistiche di cattura e da campagne scientifiche in mare permette di analizzare lo stato di sfruttamento, ovvero di stimare i tassi di sfruttamento, i livelli di biomassa dei riproduttori e la risposta delle popolazioni in funzione delle scelte gestionali alternative. L’analisi temporale del rapporto fra cattura e biomassa in mare consente, infatti, di quantificare tassi di sforzo sostenibili e di monitorare l'impatto della pesca per ciascuna specie.
La somma di tutte queste attività, insieme al monitoraggio ambientale della fascia marino - costiera, ha permesso di acquisire una notevole mole di dati utili al monitoraggio e alla valutazione della biodiversità marina, attività che sempre più sta assumendo importanza nell’ambito della salvaguardia e valorizzazione della natura.
Il Report parlerà delle tecnihe istologiche di tessuti gonadici e la loro importanza, (a livello microscopico) sul riconoscimento dello stadio di maturità che determinerà con più dettaglio e precisione la frazione deponente della specie target
The Fermi gamma ray sky: Summary of recent observations
No full textThe Fermi Gamma-ray Space Telescope was launched more than 13 years ago and since then it has dramatically changed our knowledge of the gammaray sky. With more than three billions photons from the whole sky, collected in the
energy range between 20 MeV and more than 300 GeV, and beyond 6,000 detected sources, LAT observations have been crucial to improving our understanding of particle acceleration and gamma-ray production in astrophysical sources. In this review, I will review recent science highlights from the LAT. I will focus on the recent source catalog release, as well as on the main transient phenomena seen with the LAT with multi-wavelength and multi-messenger connection
Heavy-ion physics with the ALICE detector
No full textA selection of recent results from the heavy-ion experiment ALICE at the CERN LHC, chosen to address various stages of the nucleus-nucleus reaction
Lepton flavour universality in τ decays
No full textThe evidence for Lepton Flavour Universality (LFU) violation in semileptonic B-decays has been rising over the past few years. Relying on generic effective field theory (EFT) results, it has been shown that models addressing the
B-anomalies necessarily lead, at one-loop, to deviations from LFU in τ decays at the few per-mil level. Once a (renormalizable) UV model is specified, the leading-log EFT result receives finite corrections from the matching at the UV scale. We discuss such corrections in a motivated class of models for the B-anomalies, based on an extended SU(4) × SU(3) × SU(2) × U(1) gauge sector. In this scenario, we obtain precise predictions for the effective W-boson and Z-boson couplings to leptons in terms of the masses and couplings of the new heavy fields. We confirm a few per-mil
deviation from universality, within reach of future high-precision experiments
A second resonance of the Higgs field: Theoretical motivations and experimental signals
No full textAnalytical arguments and lattice simulations indicate that, beside the known resonance of mass mh = 125 GeV, defined by the quadratic shape of the effective potential at its minimum, the Higgs field could exhibit a second heavier
excitation with mass (MH) theor = 690 ± 10 (stat) ± 20 (sys) GeV. This larger MH would measure the zero-point energy and, differently from mh, would remain finite in units of the weak scale Φ ∼ 246.2 GeV for an ultraviolet cutoff Λs → ∞. In spite of its large mass, however, the heavier state would couple to longitudinal W’s with the same typical strength of the low-mass state at 125 GeV. As such, its total decay width ΓH would be much smaller than the conventional expectation and its main production mechanism at LHC would be through gluon-gluon fusion (ggF). For an experimental check I have thus considered the ATLAS sample of 4-lepton
ggF-like events in the region of invariant mass μ4l = 620–740 GeV (l = e, μ) which extends about ±60 GeV around our central mass value. These data indicate the presence of a new resonance with mass (MH) exp = 660–680 GeV and reproduce, to high accuracy, a characteristic correlation, between resonating peak cross section σR(pp → H → 4l) and the ratio γH = ΓH/MH. This correlation is nearly insensitive
to the precise value of ΓH and mainly determined by the lower mass mh = 125 GeV. Therefore, one could also fit mh from the 4-lepton data in the high-mass range 620– 740 GeV. The result (mh) fit ∼ (125 ± 13) GeV reproduces the direct measurement of the Higgs particle mass and supports the idea that mh and the new (MH) exp are the masses of two different excitations of the same field
Age and crime: Empirical and theoretical approaches of criminal adult onset
Get PDFAccording to the age-crime curve, prevalence in crime displays an increase over the period from the late childhood to adolescence, a peak towards the end of adolescence and a downward trend afterwards during adulthood. In this context, the highest rate of desistance is observed towards the end of adolescence and the beginning of adulthood regardless of the time of antisocial or criminal onset. However, research experience has highlighted the existence of offenders who appear to engage in crime for the first-time during adulthood. The present analysis focuses on the empirical experience regarding the dimensions of the phenomenon as well as the factors associated with its occurrence. At the same time, particular reference will be made to the theoretical approaches to the phenomenon in an attempt to identify the process whose starting point is placed in minority and, during the period of transition to adulthood, leads to criminal onset and a criminal career
Preface
Get PDFIn Italy there are several physics education research (PER) groups with great and internationally recognized value, contributing to the international PER community with
publications in indexed journals and books, participating in prestigious editorial committees, and the boards of important international bodies, like European Physical Society -Physics Education Division (EPS-PED), European Scientific Education Research Association (ESERA), International Physics Education Research Group (GIREP), Multimedia Physics Teaching and Learning (MPTL). One of the 27 prestigious medals of the International Commission on Physics Education (ICPE-IUPAP) was awarded in 2018 to a
member of the Italian PER groups. However, this value is poorly exploited and supported in Italian Physics Departments, where the Italian PER community work. As a
matter of fact, the Italian PER is funded only with European or regional projects, but not through national funding plan
Research activities on radioactive waste management and on the back-end of the nuclear fuel cycle performed by the Joint Research Centre of the European Commission
Get PDFThe Euratom Research and Training Programme contributes, within its portfolio of activities, to establish and improve the scientific basis of knowledge for the safe management of spent nuclear fuel and radioactive waste. This includes
research and innovation activities undertaken by the Joint Research Centre (or JRC, the European Commission’s science and knowledge service) in its laboratories. This paper provides an overview and some highlights of the Joint Research Centre (JRC) activities which are dedicated to the safety of spent fuel and high level radioactive waste forms. The fields of experimental and modelling research address various stages of spent fuel management after discharge from the reactor core: cooling in the spent fuel pool; handling, transport, extended interim storage and retrieval
thereafter; disposal in a deep geological repository and long term behaviour of the spent fuel/waste form after disposal. The safety of the “back-end” of nuclear fuel
cycles which include U-Pu recycling and/or a “fully closed” cycle with minor actinides separation and transmutation is also a major area of research. Both normal operation and accident scenarios, which cause fuel degradation/melting, are investigated. Possible applications for legacy waste management, decommissioning, and safeguards are considered. The relevance of the research is linked to the possibility
of investigating “real” spent fuel and highly radioactive compounds using JRC’s research infrastructure, which includes hot cells and shielded facilities, and state of
the art experimental methods that are (in some cases) rare or even unique. The activities are performed in collaboration with partners and/or in the context of international initiatives. Opportunities and perspectives for enhanced cooperation, including access and sharing of infrastructure are being developed
The MICADO project and its possible upgrades
Get PDFThe radiologic characterization is a very important step in dealing with materials and waste streams generated during operational and decommissioning phases of nuclear installations. Its goal is to determine the waste package radiologic content differenting between materials that can be released from regulatory con- trol and those that require further treatment and conditioning to become a stable waste form suitable for future storage and final disposal, according to its classifica- tion. Characterization is also needed in the pre-disposal stages of radioactive waste management to demonstrate compliance with the waste acceptance criteria of the storage facilities. This work presents the strategies developed and implemented by the MICADO EU project for an in-depth and accurate waste characterization and investigation of the different radioactive waste packages considered. It presents its goals, the methods developed and the technologies used contributing to the improve- ment of the safety. Special emphasis will also be given to complementary approaches highlighting the usability of the technologies and the digitalization and accessibility of the data
Top-quark pair cross-section at √s = 13.6 TeV with the ATLAS experiment
Get PDFThe ATLAS detector started collecting data in 2022 at the centreof-mass energy √s = 13.6 TeV. In this report, an analysis of proton-proton collision data collected in August 2022 by the ATLAS detector at the LHC is shown. The analysis aim is to measure the top-quark pair production cross-section and its ratio to the Z boson production cross-section. Some of the first plots showing a comparison between Run 3 data and predictions in the eμ final state are presented