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Non solo Parigi: Giselle e le principali messinscene nei primi anni dal debutto
No full textIl saggio parla di Giselle, celebre balletto romantico, e della sua diffusione in Francia e nelle principali capitali europee nei primi anni del debutto mettendo in rilievo le problematiche relative alla trasmissione della partitura coreica originale
Plasticity-Led (Not First) Evolution: A Matter of Causal Relevance
Get PDFPhenotypic plasticity has long been a phenomenon studied in evolutionary biology, but in recent decades it has attracted renewed interest among biologists. This interest has culminated in the so-called plasticity-led evolution hypothesis, according to which phenotypic plasticity, under certain circumstances, is capable of acting as an evolutionary factor, influencing the direction of adaptive change and promoting the emergence of new phenotypic variation. This article aims to analyze this hypothesis and the controversies it has generated and to bring more clarity to a debate that is often characterized by ambiguity and conceptual confusion. We will show how this debate can best be understood as a debate about the explanatory range of the two rival (but not mutually exclusive) models, plasticity-led evolution and mutation-led evolution, and their ability to explain the origin of phenotypic variation. We will then make use of Woodward’s account of causality in biology to assess the “specific weight” that the causes theorized by plasticity-led evolution can have within evolutionary explanations. To this end, we will analyze one of the best-known cases of plasticity-led evolution in nature, the North American spadefoot toad. Our analysis leads us to conclude that models based on plasticity-led evolution can be regarded as autonomous explanans, irreducible to the action of natural selection on preexisting genetic variation. This is due to the causal role played by environmental stimuli, which is accorded greater significance than in classical approaches. Furthermore, the plasticity-led evolution hypothesis could pave the way for a reassessment of the role of development in evolutionary processes
Strength and Perceived Effort in Repetitive Upper-Limb Tasks: An OCRA Method Analysis of 900 Workers
Get PDFBackground: Work-related musculoskeletal disorders pose a significant burden on the population. The OCRA method plays a key role in assessing the risk associated with repetitive actions of the upper limbs. In this method, muscular force is evaluated based on the rate ofperceived effort (RPE) reported by the worker, which can introduce subjective bias into the assessment. This study aims to determine whether testing the worker's handgrip strength can improve the accuracy of the force assessment in the OCRA method.
Methods: Handgrip strength was measured during the risk assessment process following the OCRA method. Data were divided into specific percentile ranks based on age, gender, height, and handedness.
Results: 903 workers from 43 different Italian companies were surveyed. There was a significant difference in handgrip strength percentiles stratified by report of an RPE > 2 and those without (p = 0.047). Additionally, significant differences were found in perceived effort rates (based on the OCRA method) among workers with different levels ofstratified handgrip strength (dominant hand: p = 0.04, non-dominant hand: p = 0.02).
Conclusions: Workers performing repetitive upper limb actions at various strength levels experience different perceived effort rates during tasks. These findings suggest that measuring handgrip strength is a crucial component of risk assessments using the OCRA method. To date, this study's sample size is among the largest for this evaluation method; we believe these results could be a significant step forward in improving the risk assessment process for biomechanical overload
Opportunities and challenges for the use of human samples in translational cardiovascular research: a scientific statement of the ESC Working Group on Cellular Biology of the Heart, the ESC Working Group on Cardiovascular Surgery, the ESC Council on Basic Cardiovascular Science, the ESC Scientists of Tomorrow, the European Association of Percutaneous Cardiovascular Interventions of the ESC, and the Heart Failure Association of the ESC
No full textAnimal models offer invaluable insights into disease mechanisms but cannot entirely mimic the variability and heterogeneity of human populations, nor the increasing prevalence of multi-morbidity. Consequently, employing human samples—such as whole blood or fractions, valvular and vascular tissues, myocardium, pericardium, or human-derived cells—is essential for enhancing the translational relevance of cardiovascular research. For instance, myocardial tissue slices, which preserve crucial structural and functional characteristics of the human heart, can be used in vitro to examine drug responses. Human blood serves as a rich source of biomarkers, including extracellular vesicles, various types of RNA (miRNA, lncRNA, and circRNAs), circulating inflammatory cells, and endothelial colony-forming cells, facilitating detailed studies of cardiovascular diseases. Primary cardiomyocytes and vascular cells isolated from human tissues are invaluable for mechanistic investigations in vitro. In cases where these are unavailable, human induced pluripotent stem cells serve as effective substitutes, albeit with specific limitations. However, the use of human samples presents challenges such as ethical approvals, tissue procurement and storage, variability in patient genetics and treatment regimens, and the selection of appropriate control samples. Biobanks are central to the efficient use of these scarce and valuable resources. This scientific statement discusses opportunities to implement the use of human samples for cardiovascular research within specific clinical contexts, offers a practical framework for acquiring and utilizing different human materials, and presents examples of human sample applications for specific cardiovascular diseases, providing a valuable resource for clinicians, translational and basic scientists engaged in cardiovascular research
Damping Ratio Estimation of Heavily Damped Structures Using State-Space Modal Responses
Get PDFVibration control systems are extensively utilized in structures to enhance their resilience against earthquakes and wind forces. However, structures with significant damping exhibit atypical damping behaviors, which impose constraints on the effectiveness of traditional modal analysis methods for discerning modal responses and estimating properties. To surmount this challenge, a novel State-Space-Based Modal Decomposition approach is proposed in this study. The State-Space-Based Modal Decomposition technique adeptly extracts modal responses and identifies modal attributes from acquired data of highly damped structures. The approach accurately calculates damping ratios and natural frequencies by scrutinizing the power spectrum within the deconstructed modal response. The validity of this method is confirmed through a numerical simulation with a three-degree-of-freedom system equipped with oil dampers and experimentation of a structure outfitted with a tuned mass damper system. The findings underscore that the transfer function of the modal response in state-space encompasses both displacement and velocity transfer functions. The results demonstrate that precise estimation of modal parameters can be accomplished by suitably evaluating the participation ratio of the two response components
Unveiling ‘subtle violence’ in landscape governance and narratives: the case of the Euganean Hills
No full textThis article explores the connection between landscape and violence
through the case study of the Euganean Hills in Northeastern Italy.
Drawing from a political approach to landscape, the authors analyse
overt forms of violence imprinted on the landscape as well as more
subtle manifestations of violence embedded in institutional practices,
narratives, and participatory processes in landscape governance. The
study sheds light on how ‘subtle violence’ can be perpetuated through
the trivialisation of landscape concepts, the instrumentalization of landscapes
for tourism purposes, and the lack of genuine public participation.
By unveiling these subtle forms of violence, the article calls for a more
democratic and inclusive landscape governance that recognises the right
to landscape and fosters spatial justice. The findings have implications
for rethinking the role of institutional actors and processes in shaping
just and sustainable landscapes
Expert Strategies: Skull Base Reconstruction—Global Perspectives, Insights, and Algorithms through a Mixed Methods Approach
No full textObjective: There is limited consensus on endoscopic skull base surgery (ESBS) reconstruction principles. This study aims to generate comprehensive themes regarding ESBS reconstruction by pooling the experiences of ESBS experts, with comparison to a literature review of current published evidence. Methods: Structured qualitative interviews of ESBS experts regarding postoperative management and reconstruction of various defect locations were conducted. Results: A total of 68 experts comprising 40 academic teams across 13 countries with an average of 18 years of ESBS experience were included. We propose 10 stepwise algorithms for common skull base reconstruction scenarios based on these expert interviews. When available, the nasoseptal flap is used for all high_flow cerebrospinal leak defects. Multilayered reconstruction is favored at all anatomical subsites with increasing number of layers for increasing defect size and complexity. Heterogeneity exists in terms of inlay technique and materials, free grafting versus various pedicled flap options for low-flow defects or in the absence of a nasal septum, nasal packing, tissue sealant, lumbar drain use, and postoperative management. Commonalities and discrepancies between experts were summarized. Conclusion: Skull base reconstruction and post-ESBS management is highly complex with a wide variety of practice patterns and expert strategies. Further research of higher quality evidence is warranted to identify optimal management patterns, though the current work aims to inform surgeons on these controversial areas by drawing from numerous experiences
Voci per Nievo. Un dizionario tematico
No full textVoci per Nievo è un dizionario tematico che dà conto dei molteplici aspetti dell’opera e della personalità di uno scrittore straordinario e all’eccezionale contesto storico in cui operò. Noto soprattutto per il capolavoro delle Confessioni d’un Italiano, Ippolito Nievo (1831-61) fu infatti autore anche di poesie e novelle, pièce teatrali e pamphlet politici, articoli giornalistici e divertissement filosofici, lettere e traduzioni, e altresì assoluto protagonista del Risorgimento, in una vita tanto breve quanto intensa che lo vide partecipare alla Spedizione dei Mille e assumerne il ruolo di Vice-Intendente alle Finanze.
Da Almanacchi a Venezie, il dizionario annovera 28 “voci”, intese nel duplice significato di lemmi di accesso al mondo nieviano e di plurali espressioni dei diversi punti di vista di chi le ha redatte, in un dialogo tra metodi e approcci che converge in un tributo di (ri)conoscenza ad un autore amato.
Voci per Nievo è il risultato finale del Progetto di Ricerca di Interesse Nazionale 2017 “Ippolito Nievo e la cultura letteraria del Risorgimento: contesti, paradigmi, riscritture (1850-1870)”, che ha visto la felice collaborazione delle unità di ricerca delle università di Udine (Silvia Contarini, Principal Investigator), Padova (Attilio Motta), Perugia (Simone Casini e Sandro Gentili) e Verona (Alessandra Zangrandi), allargandosi per quest’opera a studiose e studiosi di altre università e istituzioni culturali italiane ed estere
Analysis of hydraulic loss of the pump-jet with accelerating and decelerating ducts via entropy generation theory
No full textPump-jets serve as critical propulsion systems for underwater vehicles, directly impacting navigation safety and energy efficiency. Traditional pressure-drop analysis methods, while widely adopted, exhibit limitations in spatially resolving localized energy dissipation mechanisms. This study implements entropy generation theory to systematically evaluate irreversible energy losses in pump-jet, with particular emphasis on quantifying the spatial distribution and magnitude of hydraulic losses. Through rigorous numerical investigations of accelerating and decelerating duct configurations with varying camber and attack angles, comparative analyses of energy characteristics are conducted across distinct pump-jet components. The results demonstrate that entropy generation theory proves advantageous when assessing the energy characteristics of pump-jet. Compared to accelerating duct pump-jet, the stator and pre-stator of decelerating duct pump-jet absorb a larger share of hydraulic losses, demonstrating superior hydrodynamic performance. Flow characteristics reveal that the variation of f and alpha leads to the significant influence on the entropy production in the flow field, while the instability mechanism of impeller and stator trailing vortices also share prominent diversity. Thus, f and alpha can serve as core parameters to distinguish between accelerating and decelerating ducts. Selecting appropriate parameters based on different operating conditions can significantly enhance performance and safety. Overall, this study provides thermomechanical guidelines for performance optimization through strategic geometric parameter selection under diverse operational conditions