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Are maternal pelvic floor and bony pelvic dimensions measured by 3D/4D transperineal ultrasound associated with fetal breech presentation?
Get PDFOBJECTIVES In a cohort of nulliparous women at term, the study aimed to: (1) assess the correlation between subpubic arch angle (SPA) and fetal breech presentation, (2) investigate the relationship between pelvic floor dimensions (at rest, during pelvic floor muscle contraction, and maternal pushing) and breech presentation, and (3) examine the prevalence between levator ani muscle co-activation and breech presentation. MATERIALS AND METHODS In this prospective observational study, 124 nulliparous women at term with a single fetus in either cephalic (n=93) or breech (n=31) presentation were recruited. A transabdominal scan was performed to confirm fetal presentation, followed by 3D/4D transperineal ultrasound (TPUS) to measure SPA, anteroposterior diameter (APD) and transverse diameter (TD) of the levator hiatus, and levator ani muscle hiatal area. TPUS measurements were taken at rest, during maximum pelvic floor muscle contraction, and during maximal maternal pushing. We compared maternal and neonatal characteristics and all TPUS measurements between the two groups. Additionally, we compared the prevalence of LAM co-activation between the two groups. RESULTS Women with a breech fetus had a lower BMI compared to those with a cephalic presentation (25.9±3.9 vs 27.8±5.0 kg/m², P=0.03). They also had a narrower SPA (100±9° vs 109±15°, P<0.001), smaller APD during pushing (52±11 mm vs 57±9 mm, P=0.03), and a smaller increase in APD during pushing, both in absolute terms (2.2±4.8 mm vs 5.4±5.9 mm, P<0.01) and proportionally (3.7±9.3% vs 8.7±9.8%, P=0.02). The prevalence of LAM co-activation was more than two-fold higher in women with a breech presentation (32.2% vs 13.9%, P=0.02). CONCLUSION Maternal pelvic characteristics, especially the subpubic arch angle and the ability to relax the pelvic floor during pushing, may significantly influence the incidence of breech presentation in nulliparous women at term
Hidden supermassive black holes in the deep universe
Get PDFThe existence of a large population of hidden active galactic nuclei (AGN), especially at high redshift, raises fundamental questions about their origins, their co-evolution with host galaxies, and their influence on the growth of supermassive black holes (SMBH) across cosmic time. This PhD thesis explores three key aspects of obscured AGN, with particular emphasis on high redshift: selection methods, demographic characterization, and their physical properties. I investigated these topics using a multiwavelength approach, incorporating radio, X-ray, optical, and infrared data, as well as using both photometry and spectroscopy, which is crucial for identifying and understanding these elusive sources. In the first part of this thesis, I focus on how radio observations can be used to identify obscured AGN, especially the highly obscured Compton-thick (CTK) population. I test the effectiveness of radio emission in selecting these sources both from an analytical and observational point of view, finding that with deep continuum radio observations it is possible to unveil much more heavily obscured AGN than what it is possible to do relying only on the X-rays. The thesis further investigates new spectroscopic methods for identifying obscured AGN at high redshift, where the James Webb Space Telescope (JWST) is opening new incredible opportunities for the investigation of these sources. I present three new diagnostic diagrams based on the [OIII]λ4363 auroral line, enabling the identification of AGN even in low-metallicity environments typical of the high-redshift universe, and providing a more effective tool for characterizing AGN in the JWST era. Finally, I describe the selection and the detailed multiwavelength analysis of narrow-line AGN (NLAGN) selected from the JWST CEERS survey, covering the redshifts range 2 < z < 9. I will explore their spectral properties, the effectiveness of the different emission line diagnostics diagrams, and I will provide insights on their X-ray and radio characteristics
Zooming into adolescents' identity: associations with well-being and pathways for change
No full textAdolescence is a critical developmental period during which individuals face the essential task of establishing a coherent and stable identity (Erikson, 1968), which is closely linked to their well-being (Karaś & Cieciuch, 2018). This dissertation adopts a multi-dimensional approach to examine the interplay between identity processes in key developmental domains and various dimensions of well-being. Chapter 1 outlines the theoretical framework and studies included. Chapters 2-7 present empirical research divided into two sections: Section A explores identity and well-being through four longitudinal studies, while Section B investigates identity changes in naturalistic and experimental contexts, including a mixed-methods study on study abroad experiences and a meta-analysis on psychosocial interventions. In Section A, Chapter 2 examines reciprocal associations between identity in educational and interpersonal domains and multiple well-being dimensions, including subjective, psychological, and social well-being, as well as physical health perception. Chapter 3 explores links between identity and sleep/wake cycle problems, while Chapter 4 considers the role of chronotype in influencing educational identity. Chapter 5 investigates how identity motives satisfaction is associated with subjective well-being, shedding light on underlying mechanisms. Section B focuses on identity changes. Chapter 6, using a mixed-methods design, examines how study abroad experiences shape identity development. Chapter 7 systematically reviews studies on psychosocial interventions promoting educational and professional identity. Finally, Chapter 8 summarizes findings, discussing theoretical and practical implications. Overall, this dissertation highlights the complexity of the interplay between identity and well-being, as well as the transformative role of meaningful experiences and targeted interventions, underscoring the need to support adolescents in this crucial developmental phase, helping them to develop a solid identity and enhance their well-being.L'adolescenza è un periodo di sviluppo cruciale in cui gli individui affrontano il compito essenziale di costruire un’identità coerente e stabile (Erikson, 1968), che è strettamente legata al loro benessere (Karaś & Cieciuch, 2018). Questa tesi adotta un approccio multidimensionale per esaminare l'interazione tra i processi identitari in ambiti di sviluppo chiave e diverse dimensioni del benessere. Il Capitolo 1 presenta il quadro teorico e gli studi inclusi. I Capitoli 2-7 riportano una serie di studi empirici suddivisi in due sezioni: la Sezione A esplora la relazione tra identità e benessere attraverso quattro studi longitudinali, mentre la Sezione B analizza i cambiamenti identitari in contesti naturalistici e sperimental. Nella Sezione A, il Capitolo 2 esamina le associazioni reciproche tra i processi identitari nei domini educativo e interpersonale e le diverse dimensioni del benessere, tra cui il benessere soggettivo, psicologico e sociale, oltre alla percezione della salute fisica. Il Capitolo 3 esplora i legami tra identità e problematiche legate al ciclo sonno-veglia, mentre il Capitolo 4 analizza il ruolo del cronotipo nell’influenzare l’identità educativa. Il Capitolo 5 indaga l’associazione tra la soddisfazione dei motivi identitari e il benessere soggettivo, approfondendo i meccanismi sottostanti. La Sezione B si concentra sui cambiamenti identitari. Il Capitolo 6, con un approccio mixed-methods, analizza come le esperienze di studio all'estero influenzino lo sviluppo identitario. Il Capitolo 7 esamina sistematicamente gli interventi psicosociali volti a promuovere l'identità educativa e professionale. Infine, il Capitolo 8 sintetizza i risultati, discutendone le implicazioni teoriche e pratiche. Nel complesso, questa tesi evidenzia la complessità del rapporto tra identità e benessere, nonché il ruolo trasformativo delle esperienze significative e degli interventi mirati, sottolineando la necessità di supportare gli adolescenti in questa fase cruciale dello sviluppo per aiutarli a costruire un’identità solida e migliorare il loro benessere
Inclusive seeds: a multi-informant approach to disentangle the development of attitudes toward migrant integration policies and the psychosocial adjustment of native Italian and migrant adolescents.
No full textUnderstanding how adolescents develop positive attitudes toward migrant integration policies is crucial to fostering social cohesion and well-being. This process does not occur in isolation, nor do individual characteristics solely determine it. Instead, it is shaped by various contexts, ranging from the most proximal to the most distal, in which adolescents are embedded. Moreover, studying inclusive orientations should not be limited to the majority ethnic group but should also consider minorities, as both actively participate and have to adjust to contemporary multicultural societies. In light of this, the present dissertation examined the influence of micro- (i.e., family and school) and macro- (i.e., municipality) contexts on the development of inclusive attitudes and the psychosocial adjustment of native Italian and migrant adolescents. Chapter 1 introduced the theoretical framework based on ecological systems theory, while Chapter 2 presented the Attitudes toward Migrant Integration Policies (AMIP) scale, assessing individual and generational differences. Chapter 3 explored the role of the family, highlighting that fathers played a crucial role in shaping majority and minority adolescents' inclusive orientations. Focusing on the school context, Chapters 4 and 5 showed how personal development and the school diversity climate impacted adolescents' inclusiveness and psychosocial adaptation. Regardless of the youth's ethnic background, stable educational identity fostered positive attitudes toward migrant integration policies, while equal treatment by teachers enhanced their adjustment. Chapter 6 examined the impact of ethnic and cultural diversity at the municipal level, showing that a highly diverse context could negatively affect adolescents, both with and without a migrant background, depending on their intergroup experiences. Finally, Chapter 7 summarized key findings, discussing theoretical and practical implications, emphasizing the importance of an ecological approach to fostering adolescent inclusiveness and psychosocial adaptation
Understanding business model sustainability in food production systems through Life Cycle Thinking
Get PDFThe sustainability of global food systems represents a critical challenge across developed and developing countries, considering its long-term environmental, economic and societal impacts. Business models (BM) play a vital role in shaping the food system and provide opportunities for boosting sustainability in food production. Socio-economic impacts are more complex to be assessed through quantitative measures; therefore, methods for social sustainability assessment need to be further explored for a reliable quantification of socio-economic impacts. Life Cycle Thinking (LCT) is adopted to investigate the sustainability of BM in food systems in different global regions, and can be combined with additional methodologies to encompass the complexity of socio-economic drivers and impacts in food system sustainability. This work seeks to address the following research questions: (1) How can LCT be applied to assess the sustainability performance of BM in food production? (2) How can BM be designed to foster sustainable practices in agricultural production? (3) What are the main socio-economic factors that are connected to the sustainability of food BM in different regional contexts? Three scientific works (the thesis’ chapters) collaborate to address these questions transversally. First, an assessment framework is developed to assess social handprints generated by City Region Food System initiatives on stakeholders’ well-being. Second, a case study of a horticultural farmers’ cooperative in Costa Rica drove the analysis of life cycle environmental and economic costs connected to agroecological practices to improve the cooperative’s BM sustainability. Third, Costa Rican coffee farmers were reached to understand the psychosocial and behavioural factors driving the adoption of sustainable agricultural practices in coffee production, and to unveil a social impact pathway towards farmers’ well-being based on statistical modelling. Together, these studies allow to examine the subject of sustainable BM from diverse perspectives, offering valuable implications for enhancing the socio-economic sustainability of agricultural practices
Integrated antenna technologies and wireless power transfer solutions for space and communications systems
Get PDFThis thesis centers on advancing integrated antenna technologies and wireless power transfer (WPT) systems, with a primary emphasis on space applications and additional relevance to communication. The research presents an inventive approach that integrates transparent antennas with photovoltaic (PV) panels, enabling satellites to simultaneously capture solar energy and transmit power wirelessly. This dual-function design optimizes surface utility—an essential factor for small satellites where space and weight constraints are paramount. Transparent antennas are designed using conductive mesh patterns that ensure a high level of optical transparency while maintaining strong electromagnetic performance. By optimizing antenna geometry and adjusting key parameters, such as eliminating horizontal lines to improve transparency, the study achieves a balance between transparency and antenna efficiency. The research also includes a broad investigation into the role of the solar panel’s top metal contacts, which are crucial to the performance of both the solar panel and the antenna. A central focus of this thesis is the exploration of WPT for CubeSats. By assessing power transfer networks between larger satellites and CubeSat swarms, the research demonstrates how coordinated power sharing can extend mission longevity. A key contribution is the design of a highly efficient Class-E amplifier-based inverter, which converts solar-generated power into high-frequency signals for wireless transmission. This efficient system is essential for space applications, where energy resources are limited. The design is carefully optimized to integrate seamlessly with the transparent antenna array, enabling effective wireless energy transfer with minimal losses. The findings have significant implications beyond space, particularly in terrestrial communication systems, where WPT can support the growing demand for energy-efficient solutions. By addressing key challenges in antenna transparency, solar panel integration, and efficient power conversion, this thesis contributes to the advancement of next-generation energy systems for both space-based and terrestrial applications
Emilia-Romagna coastal sediment modelling and depositional patterns
Get PDFCoastal erosion is a global problem that is projected to worsen in the context of climate change, thus prompting interest in the development of tools for predicting the coastal response to various climate scenarios. The Emilia-Romagna coastline is a case in point, and the present thesis aims to design a sediment transport model that represents the sediment dispersal patterns and the erosion and deposition patterns of the area. The numerical model used is SHYFEM-MPI, which uses a finite element method and works on unstructured triangular grids. The model offers a sediment transport module, that works with multiple sediment classes. Five distinct grain sizes are used in this thesis. To ascertain the most suitable model configuration, a sensitivity analysis was conducted. The findings revealed that the horizontal diffusion coefficient exerts minimal influence on sediment transport, and the most effective method for describing sediment transport is the Van Rijn method. A one-year simulation was conducted for the year 2019. The model demonstrated competence in depicting the along-shore sediment transport, which is the predominant transport pathway, albeit with lower concentrations than measured ones. This discrepancy is hypothesised to be attributable to an absence of sediment boundary conditions at the open boundary. Furthermore, during the flood event, the model exhibited a plume geometry that was analogous to the observed one. Following a year-long simulation period, the model exhibited erosion and deposition patterns analogous to the observed ones, and the grain size pattern began to mirror the local pattern. This thesis signifies the initial attempt to utilise a finite element model with multiple sediment classes on the Emilia-Romagna coast. The most significant challenge was the paucity of sediment data. To enhance this model further, it is recommended to take turbidity and discharge measurements at river mouths, and couple SHYFEM-MPI with a third-generation wave model
Measurement of (anti)helium production in pp collisions with ALICE at the LHC
Get PDFThe formation of light (anti)nuclei in high-energy hadronic collisions remains an open question under active theoretical and experimental investigation. An equal amount of matter and antimatter is produced at the LHC energies, enabling the investigation of (anti)nuclei formation mechanisms across several collision systems. However, with respect to simple nucleons, production rates for bound states are suppressed by about a factor 1000 in small systems for every added nucleon. For this reason, the currently available measurements are limited by large statistical uncertainties and poor granularity, warranting new studies focusing on the heavier states as helium-3 and antihelium-3, a fundamental proving ground to test statistical hadronisation and coalescence models. This work discusses the production of (anti)helium-3 in pp collisions at √s = 13.6 TeV. The measurement is carried out using data collected by ALICE in 2022, using the first pp collisions of the Run 3 of LHC. Thanks to this wealth of data, the yield of helium-3 and antihelium-3 is measured with unprecedented granularity, improving on the statistical precision with respect to results in literature by more than a factor 10. The challenges faced for the measurement with the new ALICE detector are detailed in this thesis. The results of this thesis contribute to clarifying the formation mechanisms of light antinuclei, providing a precise constrain for production models, paving the road for future measurements that will, in the longer term, be used as input to the modelling for the production of cosmic antinuclei for indirect dark matter searches
Extremos labores. Enduring traces of the pastoral tradition in contemporary european poetry (1933–2003).
Get PDFCette thèse explore persistance de la tradition pastorale dans la poésie européenne du XXe siècle, en se concentrant sur ce que l'on définit ici comme des « survivances fortes » du genre entre 1933 et 2003. L’étude retrace l’entrelacement fondamental de la réflexion métapoétique, de l’intertextualité et des tensions sociohistoriques au sein du mode pastoral. Loin d’être une forme littéraire naïve ou escapiste, la thèse soutient que la pastorale a, depuis l’Antiquité, servi de moyen pour affronter les fractures personnelles et politiques, en particulier lors de périodes de bouleversements historiques. La première partie de la thèse reconstruit le développement diachronique de la tradition pastorale européenne, depuis Théocrite et Virgile jusqu’à la Renaissance et ses transformations ultérieures. Elle examine ensuite les cadres critiques et théoriques — en particulier ceux de Thomas Hubbard, Paul Alpers, Leo Marx et Terry Gifford — utilisés pour définir et analyser cette tradition. L’approche méthodologique adoptée est de type fonctionnaliste et repose sur l’identification de deux fonctions clés dans les pastorales modernes : la fonction métapoétique (réflexions sur la poésie elle-même) et la fonction sociohistorique (engagement avec les contextes historiques et culturels). La seconde partie de la thèse est consacrée à l’analyse textuelle de poèmes de W.H. Auden, Louis MacNeice, Miklós Radnóti, Czesław Miłosz, Andrea Zanzotto et Philippe Beck. Ces poètes, à l’image du Gallus virgilien, apparaissent comme des figures scindées, qui réinvestissent le mode bucolique non pour fuir la modernité mais pour en affronter les complexités — guerre, mutations technologiques, crise écologique — à travers l’allégorie, le dialogue avec les prédécesseurs et l’innovation formelle. La thèse montre ainsi comment la tradition pastorale, que l’on croyait révolue, se révèle être une forme poétique résiliente et adaptable dans le monde contemporain.This dissertation investigates the enduring vitality of the pastoral tradition in 20th-century European poetry, focusing on what are here defined as "strong survivals" of the genre between 1933 and 2003. The study traces the foundational interplay of metapoetic reflection, intertextuality, and sociohistorical tension within the pastoral mode. Far from being an escapist or naïve literary form, the thesis argues that pastoral has served, since antiquity, as a vehicle for negotiating personal and political fracture, especially in times of historical upheaval. The first part of the dissertation reconstructs the diachronic development of the European pastoral tradition, from Theocritus and Virgil to the Renaissance and its later transformations. It then examines the critical and theoretical frameworks — particularly those of Thomas Hubbard, Paul Alpers, Leo Marx, and Terry Gifford — used to define and analyze the tradition. Central to the methodology is a functionalist approach that identifies two key dimensions in modern pastorals: the metapoetic (reflections on poetry itself) and the sociohistorical (engagement with historical and cultural contexts). The second part consists of textual analyses of poems by W.H. Auden, Louis MacNeice, Miklós Radnóti, Czesław Miłosz, Andrea Zanzotto, Philippe Beck. These poets, like Virgil’s Gallus, are seen as divided figures who reappropriate the bucolic mode not to escape modernity but to confront its complexities — war, technological change, ecological crisis —through allegory, dialogue with literary forebears, and formal innovation. Ultimately, the thesis shows how the pastoral tradition, once thought obsolete, proves to be a resilient and adaptable mode for poetic thought in the contemporary world
How does Corporate Sociopolitical Activism (CSA) affect consumers' intention to buy or boycott a brand? A self-congruity and moral balancing perspective
Get PDFCorporate Sociopolitical Activism (CSA) has gained momentum as brands increasingly take public stances on polarizing sociopolitical issues. This dissertation investigated how aligned and misaligned CSA influences consumers' intentions to buy or boycott a brand, relying on self-congruity and moral balancing perspectives. The research examined the emotional and psychological processes that underlie these consumer reactions through three studies. The first study used a bibliometric analysis to map the intellectual structure of CSA research, identifying influential contributors, thematic trends, and future directions. The second study investigated how CSA alignment impacts purchase intentions through consumer-brand identification and self-enhancement, moderated by brand CSA motivations. The third study analyzes boycott intentions, focusing on the mediating role of self-conscious emotions, including pride and guilt, and the moderating effects of moral judgment and self-brand overlap. Our findings indicate the dual CSA role in shaping boycotting and buycotting intentions by highlighting the role of psychological and emotional involvement, the alignment with consumer values, and the motivation behind the CSA activities. This dissertation contributes to the knowledge of the risks and rewards of CSA and provides theoretical and managerial implications by combining bibliometric research with psychological and emotional perspectives