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Lo studio della struttura interna del nucleone e' un tema di grande rilevanza in fisica adronica. Negli ultimi anni e' stato intrapreso un grande sforzo, sia dal punto di vista teorico che sperimentale, per ottenere una descrizione completa della struttura del nucleone al di la' dell'approccio collineare in Cromodinamica Quantistica, dove i gradi di liberta' trasversi non vengono considerati. D'altronde, sempre piu' risultati sperimentali non possono essere spiegati senza ricorrere al momento trasverso del partone $k_{T}$, al suo spin trasverso $s_{T}$ e alla loro correlazione con il nucleone. Nel formalismo dipendente dal momento trasverso (TMD), la struttura del nucleone e' descritta da otto funzioni di distribuzione partonica (TMD PDFs), che emergono come generalizzazione delle tre PDF collineari (densita', elicita' e trasversita'). La nostra conoscenza di queste funzioni e' molto limitata. Di particolare interesse e' la funzione di Boer-Mulders $h_{1}^{\perp}$, che descrive la correlazione fra il momento trasverso e lo spin trasverso di un partone in un nucleone non polarizzato. Lo scopo di questa Tesi e' contribuire alla comprensione della struttura del nucleone mediante lo studio di due osservabili TMD accessibili nella diffusione semi-inclusiva profondamente inelastica (SIDIS) di leptoni di alta energia su protoni non polarizzati, ossia le distribuzioni di momento trasverso e le ampiezze delle modulazioni nell'angolo azimutale (o asimmetries azimutali) degli adroni nello stato finale. Queste forniscono informazioni importanti sul momento trasverso dei partoni e sulla funzione di Boer-Mulders. In questa Tesi e' riassunto il lavoro fatto lunga tale linea di ricerca durante il dottorato, consistito nell'analisi completa di parte dei dati raccolti a COMPASS nel 2016. COMPASS e' un esperimento a bersaglio fisso, situato al CERN, che utilizza un fascio di muoni di 160 GeV e, nell'anno considerato, un bersaglio di idrogeno liquido. La qualita' dei dati, la stabilita' dei rivelatori e la consistenza dei dati ricostruiti sono state studiate in modo approfondito, in parallelo alla implementazione e validazione delle simulazioni Monte Carlo, necessarie per la correzione per l'accettanza e per la stima della contaminazione da processi diffrattivi. E' stata condotta un'analisi dei possibili effetti sistematici e del loro contributo all'incertezza complessiva delle misure. Le varie dipendenze cinematiche sono state trattate in dettaglio e dei risultati, confrontati con quelli gia' ottenuti in misure precedenti a COMPASS, e' stata condotta un'analisi fenomenologica. Questa Tesi e' cosi' organizzata. La struttura del nucleone nell'approccio TMD e' introdotta nel Capitolo 1, con particolare attenzione al processo SIDIS e alle osservabili ad esso associate. Il Capitolo 2 e' dedicato alla descrizione dell'esperimento COMPASS e del setup sperimentale per la presa dati del 2016. Il Capitolo 3 e' dedicato all'analisi dei dati, in termini di selezione degli eventi DIS, degli adroni prodotti nel SIDIS e delle correzioni per l'accettanza. La procedura per l'estrazione delle distribuzioni in momento trasverso e delle asimmetrie azimutali, la stima delle incertezze sistematiche ad esse associate, i risultati e la loro interpretazione sono presentati nei Capitoli 4 e 5. Il Capitolo 6 tratta della produzione diffrattiva dei mesoni vettoriali, con particolare attenzione al mesone $\rho^0$ e alla distribuzione angolare dei suoi prodotti di decadimento. Le conclusioni sono tratte nel Capitolo 7. The study of the internal structure of the nucleon is a hot topic in hadron physics. In recent years, a huge effort has been undertaken, both on the theoretical and on the experimental side, to provide a comprehensive description of the nucleon structure beyond the collinear Quantum Chromo Dynamics (QCD) approach, where all transverse degrees of freedom are assumed negligible. As a matter of fact, many experimental results can not be explained without considering the parton transverse momentum $k_{T}$, its transverse spin $s_{T}$ and the way how they correlate with the nucleon. In the recently developed QCD formalism, the nucleon structure is described by eight Transverse-Momentum-Dependent (TMD) Parton Distribution Functions (PDFs), which are generalizations of the three collinear ones (number density, helicity and transversity). To a large extent, our knowledge of these functions is still very poor. The aim of this Thesis is to contribute to the understanding of the nucleon structure through the study of two observables accessible in Semi-Inclusive Deep Inelastic Scattering (SIDIS) of high energy leptons off unpolarized protons: the transverse-momentum distributions and the amplitudes of the modulations in the azimuthal angle of the final state hadrons, the latter referred to as "azimuthal asymmetries". They give relevant information on the transverse momentum of the partons inside the nucleon and on the Boer-Mulders TMD PDF. This Thesis summarizes the work done in this direction during the Ph.D., which consisted in a complete analysis of part of the data collected in 2016 in COMPASS, a fixed target experiment at the CERN SPS using 160 GeV/$c$ $\mu^+$ and $\mu^-$ beams and a liquid hydrogen target. The data quality and the detector stability have been investigated, as well as the stability and the consistency of the reconstructed data. A significant effort has been put in the validation of the Monte Carlo simulations, necessary for the evaluation of the acceptance of the spectrometer and to estimate the contamination to the SIDIS sample by the hadrons produced in the decay of diffractively produced vector mesons (particularly $\rho^0$ and $\phi$), which give strong contributions both to the transverse-momentum distributions and to the azimuthal asymmetries of the inclusive hadrons. This diffractive process had also to be studied in detail and implemented in dedicated Monte Carlo simulations, reducing the systematic uncertainties affecting previous measurements. Other systematic effects have also been investigated, and the corresponding systematic uncertainties evaluated. A deep inspection of the various kinematic dependences has been performed. A phenomenological analysis of the new results is also presented, with a comparison of the current COMPASS findings with the previous ones obtained on a deuteron target. \\ This Thesis is organized as follows. In Chapter 1 the transverse-momentum-dependent structure of the nucleon is introduced, with a focus on the SIDIS process and the related observables. The second Chapter is dedicated to the description of the COMPASS experiment with details on the 2016 setup. The third Chapter is devoted to the data analysis, with a description of the selection of the DIS events and of the hadron samples and of the acceptance corrections. The procedure for the extraction of the transverse-momentum distributions and of the azimuthal asymmetries, the estimation of their systematic uncertainties, the results and their interpretation are presented in Chapter 4 and 5 respectively. Chapter 6 hosts a study of the exclusive diffractive vector meson production, with a focus on the $\rho^0$ vector meson. The conclusions are given in Chapter 7.

This paper analyzes the relationships between self-congruity, functional congruity, satisfaction, sport event involvement and behavioral intentions of triathlon sport travellers. The moderating effect of different training experiences is assessed in allowing these relations. 885 data were collected among triathletes participating to international triathlon competitions. A theoretical model has been developed and tested using Structural Equation Modelling (SEM). The majority of hypotheses are empirically confirmed. Regarding the moderation hypothesis, a multi-group SEM has been estimated (considering high-intensity and low-intensity sport training as moderators). Some differences between the two groups are highlighted, remarking the need to develop differential marketing strategies in active sport tourism., tourismos, Vol. 14 No. 1 (2019)

The amplitude of the modulations in the azimuthal angle distribution (azimuthal asymmetries) of hadrons produced in the semi-inclusive deep inelastic scattering on an unpolarized nucleon carries information on the intrinsic transverse momentum of the quark and on the Boer-Mulders parton distribution function. Using the data collected with a 160 GeV muon beam scattering off a liquid-hydrogen target, the COMPASS Collaboration has recently measured the azimuthal asymmetries $A^{\mathrm{cos} φ_h}_{UU}, A^{\mathrm{cos}2φ_h}_{UU}$ and $A^{\mathrm{cos}φ_h}_{LU}$ of charged hadrons. The preliminary results shown here confirm the strong kinematic dependencies observed in previous measurements.

Background: The reasons behind low adherence to the Mediterranean diet (Med-diet) are still not entirely known. We aimed to evaluate the effect of biological (i.e., sex-related) and psycho-socio-cultural (i.e., gender-related) factors on Med-diet adherence. Methods: Baseline Med-diet adherence was measured using a self-administered questionnaire among adults with ischemic heart disease (IHD) from the EVA (Endocrine Vascular Disease Approach) study. A multivariable analysis was performed to estimate the effect of sex- and gender-related factors (i.e., identity, roles, relations, and institutionalized gender) on low adherence. Results: Among 366 participants (66 ± 11 years, 31% women), 81 (22%) adults with low adherence demonstrated higher rates of diabetes, no smoking habit, lower male BSRI (Bem Sex Role Inventory) (median (IQR) 4.8 (4.1 to 5.5) vs. 5.1 (4.5 to 5.6) and p = 0.048), and higher Perceived Stress Scale 10 items (PSS-10) (median (IQR) 19 (11 to 23) vs. 15 (11 to 20) and p = 0.07) scores than those with medium-high adherence. In the multivariable analysis, only active smoking (odds ratio, OR = 2.10, 95% confidence interval, CI 1.14 to 3.85 and p = 0.017), PPS-10 (OR = 1.04, 95% CI 1.00 to 1.08, and p = 0.038) and male BSRI scores (OR = 0.70, 95% CI 0.52 to 0.95, and p = 0.021) were independently associated with low adherence. Conclusions: Male personality traits and perceived stress (i.e., gender identity) were associated with low Med-diet adherence regardless of the sex, age, and comorbidities. Therefore, gender-sensitive interventions should be explored to improve adherence in IHD.