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The Reasons to Get Vaccinated: A Cross-Sectional Study on HPV Vaccination Adherence in a Northern Italian University
No full textBackground/Objectives: Human papillomavirus (HPV) represents a major public health challenge due to its high prevalence and the complications arising from infection. The aim of the study was to investigate the reasons for adherence to the HPV vaccination campaign offered by the University of Milan to its students. Methods: A questionnaire, distributed via QR code, was utilized to investigate the motivations behind participation in the vaccination campaign, as well as the characteristics of the population participating in the vaccination campaign carried out at the University of Milan. Concurrently, a comprehensive analysis of the characteristics of students was also carried out at the vaccination sites where it was conducted, categorizing them into university hospitals and university campuses. Results: A comparison of vaccination sites revealed a significant disparity between hospitals and universities with regard to gender, age, and faculty. A higher average age (25 versus 24 years) and a higher prevalence of females (53.9% versus 51.1%) were observed in hospitals. The findings of the regression model demonstrate that demographic factors exert an influence on only two reasons for participation, with male gender proving a predictive factor for the response option entitled “It is a responsibility towards one’s partner(s)”. Furthermore, enrolment in a course of study has been found to correlate positively with the response option entitled “I have been convinced by advertising campaigns/friends/acquaintances”. Conclusions: A vaccination campaign implemented within educational institutions is a fundamental strategy for enhancing vaccination uptake rates among young population. Conversely, the utilization of health promotion interventions, such as pre-vaccination promotional campaigns, does not seem to be a pivotal factor in enhancing uptake
MONITORING PHONON DYNAMICS IN QUANTUM MATERIALS BY TIME-RESOLVED SPONTANEOUS RAMAN SCATTERING
No full textThis thesis collects the results of my work as doctoral student of the Ph.D. School in Physics, Astrophysics and Applied Physics at Università degli Studi di Milano, that has been carried out since October 2022 at the Istituto Officina dei Materiali of the Consiglio Nazionale delle Ricerche (IOM-CNR) and within the framework of Nanoscale Foundries and Fine Analysis (NFFA) facility.
My research activity has been devoted to the study of phonon dynamics in photoexcited quantum materials, employing time-resolved spontaneous Raman spectroscopy (TRRS) as the primary experimental approach. Among ultrafast spectroscopies, TRRS provides unique access to phonons and other low-energy excitations in systems impulsively
driven into transient non-equilibrium states, allowing mode-specific monitoring of their population dynamics. This makes TRRS particularly powerful for investigating electron-phonon and phonon-phonon couplings, as well as the evolution of crystal symmetries after photoexcitation. Motivated by the broad span of applications of this
technique and by its complementarity with other ultrafast spectroscopies targeting electronic, lattice or spin degrees of freedom, a dedicated TRRS setup was developed at the NFFA-SPRINT laboratory, hosted in the premises of the FERMI@Elettra facility (Elettra-Sincrotrone Trieste).
This booklet thus summarizes my work for the commissioning and characterization of the new setup, and presents the results from three case studies addressing the properties of semiconductors, 2D chalcogenides and a strong correlated oxide. In a first experiment, the phonon relaxation dynamics of silicon is investigated. The possibility of tuning the phonon-phonon anharmonic interaction is explored by varying the external temperature and the excitation density. Furthermore, the photodoping dynamics is directly monitored via a Fano interference effect between electronic and phononic Raman scattering. A second experiment, targeting bulk and single-layer MoS2, reveals a photodoping-induced phonon frequency renormalization and a long-lived excitation anisotropy in the phonon subsystem, dictated by mode symmetries and inaccessible under equilibrium conditions. In a third experiment, TRRS is employed to monitor the evolution of the lattice symmetry of magnetite and the phonon-specific energy flow while triggering a photoinduced Verwey phase transition
Zooming into the water snow line: High-resolution water observations of the HL Tau disk
No full textContext. Water is one of the central molecules for the formation and habitability of planets. In particular, the region where water freezes out, the water snow line, could be a favorable location for planets to form in protoplanetary disks.
Aims. We aimed to spatially resolve the water emission in the HL Tau disk using high-resolution ALMA observations of the H2O 183 GHz line (Eu = 205 K). We compared the spatially resolved H2O emission with that of H13CO+, a chemical tracer of the water snow line, to observationally test their anticorrelation. In addition, we aimed to quantify the fraction of the water reservoir hidden by optically thick dust at ALMA wavelengths versus far- and mid-IR wavelengths.
Methods. We used high-resolution ALMA observations to spatially resolve the H2O 31,3–22,0 line at 183 GHz, H13CO+ J = 2–1, and the SO 44–33 transition in the HL Tau disk. A rotational diagram analysis was used to characterize the water reservoir seen with ALMA and compare it to the reservoir visible at mid- and far-IR wavelengths.
Results. We find that the H2O 183 GHz line has a compact central component and a diffuse component that is seen out to ∼75 au. A radially resolved rotational diagram shows that the excitation temperature of the water is ∼350 K, independent of radius. The steep drop in the water brightness temperature outside the central beam of the observations where the emission is optically thick is consistent with the water snow line being located inside the central beam (≲6 au) at the height probed by the observations. Comparing the ALMA lines to those seen at shorter wavelengths shows that only 0.02–2% of the water reservoir is visible at mid- and far-IR wavelengths due to optically thick dust hiding the emission, whereas 35–70% is visible with ALMA. An anticorrelation between the H2O and H13 CO+ emission is found, but it is likely caused by optically thick dust hiding the H13CO+ emission in the disk center. Finally, we see SO emission tracing the disk and, for the first time in SO, a molecular outflow and the infalling streamer out to ∼2′′. The velocity structure hints at a possible connection between the SO and the H2O emission.
Conclusions. Spatially resolved observations of H2O lines at (sub)millimeter wavelengths provide valuable constraints on the location of the water snow line while probing the bulk of the gas-phase reservoirs
Association of Single-Nucleotide Polymorphisms in Sweet Taste Perception and Intake Genes with Primary Ciliary Dyskinesia and Its Clinical Phenotypes
No full textPrimary ciliary dyskinesia (PCD) is a congenital motile ciliopathy causing impaired mucociliary clearance and characterized by recurrent respiratory infections affecting both the upper and lower airways. Several genes involved in taste perception pathways are expressed in extraoral tissues and have recently emerged as regulators of airway immune responses. This study aimed to (1) analyze potential correlations between PCD clinical manifestations and (2) investigate whether genetic variants within sweet signaling genes (SweetG) could be associated with PCD features. A total of 17 SNPs in nine SweetG were tested for differences in allele frequency between patients and the gnomAD European reference population using a binomial test. Regression models were used to evaluate associations between SweetG-SNPs and clinical features of patients. A cohort of 34 patients (10–69 years, 44.1% male) was included in the study. Regarding (1), a moderate/high correlation was identified among the clinical manifestations of the pathologies. Regarding (2), the minor alleles of rs5415 (SLC2A4 gene) and rs838133 (FGF21 gene) were less frequent in patients than in the reference population (p < 0.05). In addition, rs5415 and rs838133 were associated with the presence of chronic rhinosinusitis and situs inversus, respectively (p < 0.05). This study reveals associations between SweetG-SNPs and PCD as well as its specific clinical features, suggesting a potential link between sweet signaling pathways and PCD clinical variability. Although larger multicenter studies are warranted to validate these findings, they represent a promising area of research that can enhance our understanding of PCD and elucidate the genetic basis of clinical manifestations associated with the disease
Serum Neurofilament Light Chain and Glial Fibrillary Acidic Protein as Differential Biomarkers of Response to Dimethyl Fumarate and Ocrelizumab in Multiple Sclerosis
No full textMultiple sclerosis (MS) is a chronic inflammatory and neurodegenerative disease. Quantify-
ing neuronal damage is a critical step for patient care. Neurofilament light chain (sNfL) and
glial fibrillary acidic protein (sGFAP) are the most promising serum biomarkers reflecting
neuronal damage and astroglial activation, respectively. This study analyzed sNfL and sG-
FAP in 177 MS patients and 71 healthy controls (HCs) using SIMOA technology, classifying
patients as responders (Rs) or non-responders (NRs) based on “No Evidence of Disease
Activity 3” (NEDA-3) status during two years of treatment. Longitudinal analyses were per-
formed for Dimethyl fumarate (DMF) and Ocrelizumab (OCRE) treatment. Biomarker–age
correlation analysis in HCs confirmed correlation between both NfL and GFAP, with age
and cut-off values specific for age decades being calculated. Both biomarkers were higher in
MS patients compared to HCs. sNfL showed a significant increase in NR patients overall. In
contrast, sGFAP was elevated in the low-to-moderate-efficacy treatment agents (LETAs) NR
group and also in the DMF NR subgroup, suggesting that it monitors persistent astrogliosis.
Longitudinal analysis showed that both biomarkers decreased during DMF treatment after
one year. During OCRE treatment, sNfL rapidly reduced to HC levels within one year,
while sGFAP decreased only after two years. This highlights that OCRE acts differently on
the pathological processes linked to the two biomarkers
A Molecular and Functional Investigation of the Anabolic Effect of an Essential Amino Acids’ Blend Which Is Active In Vitro in Supporting Muscle Function
No full textBackground/Objectives: Essential amino acids’ (EAAs) biological effects depend on both
gastrointestinal stability and intestinal bioavailability. A commercially available EAA blend
has previously shown to be highly bioaccessible and able to inhibit the DPP-IV enzyme
both directly and at a cellular level following simulated digestion in vitro. In light with this
consideration, the present study aimed to evaluate the intestinal in vitro bioavailability of
GAF subjected to INFOGEST digestion (iGAF) and to investigate the metabolic effects of its
bioavailable fraction on muscle cells using an integrated Caco-2/C2C12 co-culture model.
Methods: Differentiated Caco-2 cell lines were treated with iGAF, and amino acid transport
was quantified by ion-exchange chromatography. The basolateral fraction containing
bioavailable EAAs was used to treat differentiated C2C12 myotubes for 24 h. Western
blot analyses were performed to assess the activation of anabolic and metabolic pathways,
including mTOR, Akt, GSK3, AMPK and GLUT-4. Results: More than 50% of each EAA
present in iGAF crossed the Caco-2 monolayer, with BCAAs and phenylalanine particularly
enriched in the basolateral fraction. Exposure of C2C12 myotubes to the bioavailable
iGAF stimulated mTORC1 activation and increased the phosphorylation of Akt and GSK3,
indicating an enhanced anabolic response. At a cellular level, iGAF also elevated the
p-AMPK/AMPK ratio, suggesting activation of energy-sensing pathways. Moreover,
GLUT4 protein levels and glucose uptake were significantly increased. Conclusions: The
study focuses exclusively on a cellular model, and results suggested that iGAF is highly
bioavailable in vitro and that its absorbed fraction activates key anabolic and metabolic
pathways of skeletal muscle cells, enhancing both protein synthesis signaling and glucose
utilization in vitro
EXPLORING UNPRECEDENT SYNTHETIC ROUTES FOR CHIRAL AMINO DERIVATIVES
No full textThis PhD thesis focuses on the development of unprecedented synthetic strategies for the preparation of chiral amino derivatives through the integration of photoredox catalysis, organocatalysis, transition-metal catalysis, and continuous-flow chemistry. The work explores the synthetic potential of light-driven processes to access reactive open-shell intermediates under mild and sustainable conditions, enabling transformations that are difficult or inaccessible using conventional two-electron pathways.
A major part of this research is devoted to the generation and exploitation of nitrogen-centered radicals, with particular emphasis on nitrogen lactam radicals. Novel precursors and activation strategies were developed to access these intermediates under visible-light photoredox conditions. Their reactivity was investigated in asymmetric organophotoredox processes, leading to the enantioselective α-functionalization of aldehydes. This methodology enables the direct construction of C–N bonds with high stereocontrol and was successfully applied to the synthesis of pharmaceutically relevant compounds, including a key intermediate of levetiracetam.
The thesis also explores metallaphotoredox catalysis as a powerful platform for complexity-building reactions. In particular, deoxygenative arylation strategies were applied to the synthesis of dopamine-like compounds, both in batch and continuous-flow conditions, demonstrating the advantages of flow chemistry in terms of efficiency, scalability, and reaction control.
Additional studies include asymmetric reductions and functional group manipulations carried out in collaboration with industry, as well as research activities conducted during an international research stay at the university of Cologne, covering asymmetric epoxidation and the development of novel cross-linking reagents for protein structure analysis.
Overall, this work highlights the versatility of dual catalytic strategies and photochemical approaches for the sustainable synthesis of chiral nitrogen-containing molecules, offering new tools and perspectives for modern synthetic organic chemistry
Light-Driven Stereoselective Aryl Bisenone Cycloaddition: A Metal-Free Strategy for the Construction of Functionalized Pyrrolidines and Tetrahydrofurans
No full textIn this study, we report an exploratory study on the reductive cyclization of nitrogen- and oxygen-containing aryl bisenones, enabling the efficient synthesis of highly functionalized pyrrolidines and tetrahydrofurans under visible light irradiation. The transformation proceeds through a photocatalytic cyclization promoted by catalytic amounts of Eosin Y, with Schreiner's thiourea and Hantzsch ester acting as mediators under visible green light irradiation. The transformation is stereoselective and affords the five-membered heterocycle as a single, trans isomer. Moreover, the introduction of chiral oxazolidinone auxiliaries onto aryl bisenone precursors allowed the formation of chiral, highly substituted trans pyrrolidines and tetrahydrofurans in good yields, although with modest stereoselectivities
Measurement of the top-quark Yukawa coupling from tt production in the lepton+jets final state using pp collisions at √s = 13 TeV with the ATLAS detector
No full textThe top-quark Yukawa coupling is extracted from the distribution of the top-quark pair () invariant mass in proton-proton collisions using 140 fb−1 of data at TeV collected in 2015–2018 by the ATLAS experiment at the Large Hadron Collider. In the region near the production threshold, the invariant mass spectrum is sensitive to electroweak virtual corrections, including contributions from Higgs boson exchange, thereby providing sensitivity to the top-quark Yukawa coupling. This is the first measurement in ATLAS that aims to obtain this coupling exploiting this approach. The system is reconstructed in the single-lepton final state, requiring exactly one isolated electron or muon and at least four jets with at least two identified as originating from b-quarks. The measured Yukawa coupling is found to be in good agreement with the Standard Model prediction. An upper limit on the top-quark Yukawa coupling strength of Yt < 2.1 relative to the Standard Model prediction is observed at 95% confidence level, consistent with the expected sensitivity
UV-C Irradiation Effectiveness on Mpox-Virus-Contaminated Surfaces
No full textIntroduction: Mpox virus (MpoxV), an emerging zoonotic pathogen, has recently caused global concern due to increasing outbreaks beyond its traditional endemic regions. While transmission primarily occurs via close contact, fomites are also suspected of contributing. This study aims to evaluate the effectiveness of UV-C irradiation on MpoxV-contaminated surfaces. Methods: the virucidal activity of UV-C (254 nm) irradiation on MpoxV applied to plastic, glass, and stainless-steel surfaces was assessed. Using a viral stock of 2.49 × 105 TCID50/mL, the samples were exposed to increasing UV-C doses. Viral titers were quantified through TCID50 and plaque assays. Results: A UV-C dose of 6.34 mJ/cm2 achieved a >2-log reduction of viral load, below the detection limit (31.6 TCID50/mL), on all tested surfaces. EC90 values were determined as 3.33 mJ/cm2 (plastic), 0.81 mJ/cm2 (stainless steel), and 1.98 mJ/cm2 (glass). No viable virus was detectable post-treatment at these doses on plastic and stainless steel while the titer was significantly reduced on glass. Conclusions: UV-C irradiation at low doses effectively inactivated MpoxV on various fomites. These findings support UV-C as a rapid and effective environmental disinfection strategy in healthcare and community settings to prevent indirect transmission of MpoxV