Acta Orientalia Vilnensia
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The Many Lives of Dark Matter: WIMPs, FIMPs, and EFTs
No full textFrom Weakly Interacting Massive Particle (WIMPs) to Feebly Interacting Massive Particles (FIMPs), the landscape of Dark Matter models has expanded as experimental constraints have evolved. This thesis follows that evolution.
We begin with the standard WIMP paradigm, where increasingly precise experiments have imposed stringent bounds on the simplest realizations. A number of well-motivated extensions, such as models with additional scalar or gauge bosons, are reviewed to illustrate how Dark Matter searches have evolved alongside these constraints.
To address the tightening bounds, we next examine scenarios in which Dark Matter–nucleon scattering arises at loop level. Such loop-suppressed interactions alleviate the tension with direct detection experiments while preserving the thermal relic picture, thus keeping WIMPs viable within a modified framework.
We then turn to the freeze-in mechanism, where Dark Matter is produced through feeble couplings in the early Universe. While these scenarios naturally evade direct searches, their tiny couplings make them almost impossible to test. To open up new possibilities, we explore a non-standard cosmological history with a low reheating temperature. In this setup, viable parameter space emerges with couplings large enough to be experimentally probed, providing a striking contrast with the WIMP case.
Finally, we move beyond specific models to an Effective Field Theory (EFT) approach, where mediators and interactions are organized in a systematic, gauge-invariant framework. This extended EFT captures the essential features of a broad class of ultraviolet completions and provides a model-independent language to confront theory with experiment, offering a versatile tool for future Dark Matter searches
Il danno alla biodiversità dopo la disciplina della Nature Restoration Law
No full textLa recente adozione del Regolamento 2024/1991, c.d. Nature Restoration Law, introducendo obiettivi di ripristino degli ecosistemi degradati, giuridicamente vincolanti per gli Stati, e rafforzando il nesso tra tutela della biodiversità e lotta al cambiamento climatico, sollecita una riflessione sulla fattispecie di danno alle specie e agli habitat naturali protetti di cui alla Direttiva 2004/35 e al d. lgs. 152/2006; in particolare sulle differenze strutturali e funzionali tra il modello di responsabilità ambientale fondato sul principio «chi inquina paga» e la logica di public enforcement insita nel Regolamento, nonché sull’idoneità della disciplina di protezione della biodiversità quale strumento di lotta e di mitigazione degli effetti del cambiamento climatico
The Rising Burden of Childhood Obesity: Prevention Should Start in Primary School
No full textBackground: The increasing rates of childhood obesity (CO) are an ongoing problem. We focused on the adherence to the Mediterranean diet (MD), physical activity, and sleep habits of preschool children in order to investigate the relationship between lifestyle habits and health outcomes through parental perception. Methods: In the context of "EpPOI: Education to prevent CO", we investigated physical activity (PA) and sleep hygiene using an online survey for caregivers. Parents also completed the Mediterranean Diet Quality Index for children and adolescents (Kid-Med) questionnaire. Results: A total of 5.3% of the interviewees achieved a score indicating an adequate adherence to the MD. Additionally, 50.5% of children ate sweets every day, and 80% skipped breakfast. We also found that the parents' perceptions of their children's PA were a predictor of MD adherence, and PA was also positively correlated with fruit consumption [p < 0.034], vegetable consumption [p < 0.015], and fish consumption [p < 0.005]. Conclusions: Parents seem to be oriented towards a healthy lifestyle, but the children's level of adherence to the Mediterranean diet is poor. CO prevention requires a synergic effort that includes an adherence to healthy eating patterns such as the MD and a greater awareness of parents on the importance of adopting a healthy lifestyle at an early age
Develop High-Performance Cu-Based RWGS Catalysts by Controlling Oxide–Oxide Interface
No full textThe high-temperature reverse water–gas shift (RWGS) is an industrially relevant reaction. Cu-based catalysts easily sinter and deactivate under these conditions. We demonstrate that it is possible to obtain high-performance and stable catalysts by modifying the mechanism of action. Cu/CeOx-MgO (denoted as Cu/CexMgy) catalysts were developed in which Cu nanoparticles mostly generate spillover H that migrates to support sites where CO2 is selectively reduced, with the rate controlled by the oxide–oxide CeOx-MgO interface. An optimal Cu/Ce0.05Mg0.95 catalyst (in terms of performance at the lowest possible Ce amount) exhibits a near-equilibrium CO2 conversion with a reaction rate of 516.0 μmol·gcat–1·s–1, near-total selectivity to CO at 600 °C, and a high space-velocity of 300,000 mL·gcat–1·h–1. These are among the top performances in the RWGS reaction. Extensive characterization data have proven that the surface-abundant Ce-[Ov]-Mg sites play a critical role in CO2 adsorption/activation as well as the carrier for the spillover of hydrogen species. The mechanism is substantially different from those indicated for Cu-based catalysts for CO2 hydrogenation. By decoupling H and CO2 activation sites and realizing efficient surface mobility of H-spillover species via an enhanced oxide–oxide interface, it is possible to maintain the overall stability and activity of the catalyst when the Cu nanoparticles sinter at a high temperature (i.e., ≥600 °C)
Radar-Based Deep Learning for Gait Smoothness Estimation: A Feasibility Study
No full textThis study investigates the feasibility of using radar-based deep learning models to estimate gait smoothness, a key biomechanical parameter associated with motor control and rehabilitation outcomes. Traditional gait assessment methods, such as optoelectronic motion capture and wearable sensors, are often costly, intrusive, or require controlled environments. Radar-based approaches offer a promising alternative by enabling contactless, continuous monitoring of human movement. In this study, sixty healthy participants walked on a treadmill at three different speeds (2, 4, and 6 km/h) while their three-dimensional body center-of-mass (BCoM) velocity was recorded using an optoelectronic system, which served as the ground truth for smoothness estimation. Simultaneously, micro-Doppler radar signals were acquired and processed into spectrograms representing movement dynamics. Nine convolutional neural networks were trained to predict BCoM smoothness from radar-derived decibel-intensity matrices, with a dedicated model for each combination of walking speed and movement component (anteroposterior, mediolateral, and craniocaudal). The models achieved mean absolute percentage errors below 10% in most conditions, except for the anteroposterior component at 6 km/h, where error rates reached 14.4%. These findings suggest that radar-based deep learning can effectively estimate gait smoothness, particularly at lower walking speeds, and holds potential for real-world applications in clinical gait assessment and rehabilitation monitoring. Despite promising results, challenges remain regarding model generalization, especially at higher speeds where gait variability increases. Future research should explore more advanced deep learning architectures, such as residual networks or attention-based models, and extend the approach to clinical populations with neurological or musculoskeletal disorders. If validated in diverse conditions, radar-based smoothness estimation could provide a novel, unobtrusive tool for assessing gait quality in both clinical and everyday settings
Severe Diabetic Ketoacidosis in Children with Type 1 Diabetes: Ongoing Challenges in Care
No full textDiabetic ketoacidosis is the most common acute complication in children and adolescents with type 1 diabetes, and contributes significantly to morbidity, mortality, and healthcare burden. This review aims to explore the multifaceted aspects of severe diabetic ketoacidosis in pediatric age, including its epidemiology, pathogenesis, risk factors, complications and emphasizing advances in prevention strategies. Incidence rates vary due to influences from geographic, socioeconomic, cultural and demographic factors. Pathogenesis is linked to insulin deficiency and an excess of counter-regulatory hormones, which disrupt glucose, protein, and lipid metabolism, causing hyperglycemia, ketosis, acidosis, dehydration, and electrolyte imbalances. According to the International Society for Pediatric and Adolescent Diabetes guidelines, severe diabetic ketoacidosis is characterized by a pH < 7.1 or bicarbonate < 5 mmol/L. This condition can lead to a wide range of life-threatening complications, including cerebral edema that represents the leading cause of death. Several prevention strategies, including awareness campaigns, early diagnosis of diabetes, regular monitoring and management, effective insulin therapy, education, access to healthcare and technological assistance, may contribute to reduce the risk of severe diabetic ketoacidosis episodes in children and adolescents
Bordering as the Breaking Force of Border Subjects
No full textBorder Studies scholars have long since considered borders neither as given entities nor merely as markers and maintainers of state sovereignty. They have shifted their perspective from the static notion of a border to a procedural understanding of the bordering as a process of relations between power and people (Pijpers, Van der Velde, Van Houtum, Van Naerssen, Vaughan-Williams). Beyond their function as demarcations that delineate distinct territories, they consider borders as disciplinary mechanisms of power as they are erected specifically to restrict undesirable classes of humans (Geddes, Häkli, Mountz). This paper aims to elaborate on the role of borders in everyday life and how of bordering, drawing upon Judith Butler’s thought. Based on Foucauldian concept of governmentality, Butler shows how norms operate to decide the question of who will be a human subject. The other against which the human is made by norms is a border subject, i.e. the inhuman, the beyond the human, the less than human, the border that secures the human in its ostensible reality. The power of norms is performative, as it homogenizes and excludes the non-conforming. However, the performativity is aporetic. On the one hand, performative power is a disciplining exercise that normalizes, configuring the normative standard, on the basis of which subjects are either recognised as normal or categorised as abnormal. On the other hand, considering that the performative efficacy of a norm depends on being repeated, an unconventional repetition can act as a breaking force, as a process involving performative bottom-up negotiations conducted by those who inhabit the borderland or are born crossing the normative border. These weak individuals at the borderline perform work that does and undoes the meaning of the borders, which can thus be accounted for in their double-function as both markers of belonging and places of becoming (Brambilla)
Pre-Silicon Accurate SPICE Modeling of Trench MOSFETs via Advanced TCAD Simulations and Dynamic Validation
No full textThis work presents a novel and fully virtual flow for extracting the SPICE model of a power MOSFET, starting exclusively from TCAD simulations. Unlike traditional approaches that rely on experimental silicon data, our methodology enables designers to optimize the device performance and extract accurate electrical parameters before any physical prototyping is required. By leveraging advanced TCAD tools, we generate a realistic device structure and obtain all the key electrical characteristics, which are then used for precise SPICE model extraction and macromodel integration. The extracted model is dynamically validated using a gate-charge test performed identically in both the TCAD and SPICE environments, demonstrating excellent agreement with less than a 2% error in the charge quantities, Qgs and Qgd. This approach proves that initial silicon prototyping can be confidently bypassed, and it is highly innovative because it enables designers to achieve highly faithful device simulations before hardware fabrication. This significantly reduces the need for costly and time-consuming prototyping and design re-spins, accelerating the development process while enhancing the accuracy in terms of the transient and dynamic characteristics of MOSFETs designed for specific applications; in our case, for an e-fuse to be integrated into a more complex system
Proprietà protettive e antivirali dell'estratto di tegumento di mandorla in cellule U937: dalla riduzione dello stress ossidativo alla modulazione dell'infezione da parte di HSV-1.
No full textAlmond skin, rich in polyphenols, is increasingly studied for its antioxidant and antiviral
properties. Recent research has highlighted its potential as a functional ingredient in healthrelated
applications. The aim of this thesis was to evaluate the antioxidant and antiviral
effects of almond skin extract (ASE) obtained from the Sicilian cultivar "Fascionello" and to
investigate the underlying molecular mechanisms using an in vitro model of human
monocytic U937 cells.
In the first phase, in vitro studies confirmed the antioxidant properties of ASE. Data
demonstrated that ASE pretreatment significantly inhibits intracellular ROS production and
protects cells from apoptosis induced by oxidative stress.
In a second experimental phase, three different storage conditions were tested to identify
potential changes in the polyphenolic profile and antioxidant activity of almond skin over
time. The goal was to establish an optimal storage protocol to preserve its bioactivity. Results
showed that the antioxidant activity of ASE is retained when stored at 4°C in the dark for up
to six months after harvesting, while other conditions led to a progressive decline in efficacy.
Lastly, the antiviral effects of almond skin polyphenols were investigated as a function of
dose and time to identify the phases and molecular mechanisms through which these
compounds interfere with the herpes simplex virus type 1 (HSV-1) life cycle. The studies
revealed that ASE pretreatment effectively inhibits HSV-1 replication in U937 cells by
interfering with the viral entry phase. This likely involves modulation of the host cell receptor
HVEM, critical for membrane fusion and viral penetration.
In conclusion, the results of this thesis provide robust evidence supporting the antioxidant
and antiviral properties of almond skin. When optimally stored to preserve its bioactive
compounds, this by-product can serve as a valuable resource for pharmaceutical and
nutraceutical applications. Moreover, valorizing Avola almond by-products promotes a
circular economy model, facilitating optimal management of the agri-food industry waste
and contributing to environmental sustainability