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Noise Source Identification for the Unsteady Low-Pressure Turbine Flow Fields
No full textThe article presents a data processing methodology to identify the noise sources in low-pressure turbine (LPT) stages and their relative importance. Scale adaptive simulation (SAS) has been carried out on a geometry reproducing the midspan blade section of an entire LPT stage. The proper orthogonal decomposition (POD) is applied to data matrices constructed with the velocity and the pressure fields in order to distinctly extract the coherent structures responsible for velocity fluctuations and pressure waves (i.e., POD modes from the corresponding kernel), their temporal evolution and energies. The cross-correlation matrices of the pressure modes and the velocity modes reveal the degree of coupling between pressure and velocity oscillations, thus highlighting the modes linked to the same flow phenomena. The results show that the periodic vortex shedding at the stator trailing edge emits strong pressure waves, and the upstream-propagating waves reflect against the adjacent stator suction surface. The POD modes related to the rotor-stator interaction show peak amplitudes at the blade passing frequency and its harmonics and their shapes mimic the potential interaction in the stator domain and the migration of viscous wakes in the rotor domain. The POD modes with lower energy content correspond to the stochastic turbulent structures originated from the turbulent boundary layers as well as those carried by the vane and blade wakes. The biggest noise sources of the current flow fields are identified to be the von Karman vortex street downstream the stator trailing edge and the rotor-stator interaction
Immunotherapy for resectable NSCLC: neoadjuvant/perioperative followed by surgery over surgery followed by adjuvant. Systematic review and meta-analysis with subgroup analyses
No full textBackground: Immunotherapy has rapidly changed the treatment of early-stage non-small-cell lung cancer (NSCLC) in recent years. We aimed to summarize available evidence on the use of immunotherapy in neoadjuvant/perioperative and adjuvant settings for resectable NSCLC and explore some controversial subgroups. Materials and methods: Systematic literature research was carried out for randomized controlled trials of neoadjuvant/perioperative chemo-immunotherapy or adjuvant immunotherapy for resectable NSCLC. Separate meta-analyses for neoadjuvant/perioperative or adjuvant immunotherapy were carried out. Subgroup analyses were also carried out to estimate the effect of immunotherapy according to tumor histology, stage, programmed death-ligand 1 (PD-L1), age, sex and smoking status. Results: Out of 6005 records screened, a total of 11 trials met the inclusion criteria. This pooled analysis showed that patients receiving neoadjuvant or perioperative chemo-immunotherapy had significantly better event-free survival (EFS) compared with those treated with neoadjuvant chemotherapy alone [hazard ratio (HR) 0.58, 95% confidence interval (CI) 0.51-0.66]. Similarly, adjuvant immunotherapy also led to improved outcomes (HR 0.85, 95% CI 0.77-0.94). However, among patients with stage II NSCLC, neoadjuvant/perioperative chemo-immunotherapy demonstrated EFS benefit (HR 0.69, 95% CI 0.54-0.88), while no significant EFS benefit was observed with adjuvant immunotherapy (HR 0.81, 95% CI 0.63-1.05). Similarly, there was an improvement in EFS for patients with squamous-cell carcinoma who received neoadjuvant/perioperative chemo-immunotherapy versus neoadjuvant chemotherapy (HR 0.56, 95% CI 0.45-0.68) and for PD-L1 < 1% (HR 0.77, 95% CI 0.65-0.93), whereas such improvement was not evident with adjuvant immunotherapy (HR 0.93, 95% CI 0.76-1.13 and HR 0.85, 95% CI 0.71-1.01, respectively). Overall survival analysis demonstrated a significant benefit from neoadjuvant/perioperative immunotherapy (HR 0.65, 95% CI 0.53-0.81), but not with adjuvant immunotherapy (HR 0.91, 95% CI 0.76-1.10). Conclusions: Our results indicate that neoadjuvant/perioperative immunotherapy should be considered the standard. This should be preferred over upfront surgery, also in stage II, PD-L1-negative and squamous histology
Charging free fermion quantum batteries
No full textThe performances of many-body quantum batteries strongly depend on the Hamiltonian of the battery, the initial state, and the charging protocol. In this article we derive an analytical expression for the energy stored via a double sudden quantum quench in a large class of quantum systems whose Hamiltonians can be reduced to 2x2 free fermion problems, whose initial state is thermal. Our results apply to conventional two-band electronic systems across all dimensions and quantum spin chains that can be solved through the Jordan-Wigner transformation. In particular, we apply our analytical relation to the quantum Ising chain, to the quantum XY chain, to the cluster Ising and to the long range SSH models. We obtain several results: (i) The strong dependence of the stored energy on the quantum phase diagram of the charging Hamiltonian persists even when the charging starts from a thermal state. Interestingly, in the thermodynamic limit, such a strong dependence manifests itself as non-analyticities of the stored energy corresponding to the quantum phase transition points of the charging Hamiltonian. (ii) The dependence of the stored energy on the parameters of the Hamiltonian can, in the Ising chain case, be drastically reduced by increasing temperature; (iii) Charging the Ising or the XY chain prepared in the ground state of their classical points leads to an amount of stored energy that, within a large parameter range, does not depend on the charging parameters; (iv) The cluster Ising model and the long range SSH model, despite showing quantum phase transitions (QPTs) between states with orders dominated by different interaction ranges, do not exhibit super-extensive, i.e. more than linear in the number of sites, scaling of the charging power
Structural Optimisation of a Cable-Driven Hyper-Redundant Manipulator*
No full textOptimising manipulators for a high payload-to-weight ratio enables them to carry heavier loads while maintaining agility and ease of movement in confined spaces. This paper offers a methodological approach for the structural optimisation of an eight-degree-of-freedom, fully actuated, cable-driven hyper-redundant manipulator. The proposed methodology includes a Gaussian process regression model for predicting unforeseen stresses and load sets. The model was trained using simulation results from structural analysis and new load and stress combinations were generated to account for unforeseen load conditions. The generative design method is then used to generate the optimised geometry. Finally, the extreme value analysis was used for critical load threshold identification, and the generated geometry was structurally verified using the load cases that generate stresses over the derived threshold. The design was then analysed using finite element analysis for its validity. The presented work outlines the possibility of hybrid optimisation techniques for high-performance robotic structures for a wide range of tasks in unpredictable operating conditions
Investigating Port Spatiality: Tools for a Spatial Approach to Port Clusters
No full textToday, half of European port managing bodies administer two or more ports. Contemporary port‐city territories are increasingly shaped by processes of “spatial clustering,” which call for a reassessment of the tools used to investigate and design these areas. Port clusterization refers to the administrative aggregation of two or more ports into clusters, a phenomenon that has the potential to affect port spatiality by defining a new spatial typology of ports, characterized by polycentricity and territorial extension. Despite the absence of established theories and tools for analysing such extended spaces, the rise of port clusters is giving way to new governance models for optimizing coastal areas and specializing land–sea infrastructures. This article, part of the EU‐funded PULSE (The Port‐clUster LandScapE) project, examines the impacts of port clusterization by introducing the concept of “port‐cluster landscapes”—whose investigation contributes to developing a spatial and design‐based approach to ports. In this context, the port‐cluster landscape emerges as a spatial typology of interconnected ports and overlapping flow systems. Methodologically, the article outlines the tools formulated to study two Italian port clusters, including multi‐level maps and the Indicator System, a set of 12 spatial indicators conceived within the framework of the project and being applied to these cases. Ultimately, the article explores port spatiality, highlighting the need for new regional collaborations and spatial reconceptualization, which can be fostered through transformative design projects in the context of port clusterization
La Mère Marie Marguerite Balland (1612-1707), fondatrice du monastère de la Visitation de Modène (1669) et directrice de conscience de Maria Beatrice d’Este, reine d'Angleterre
No full textLa Mère Marie Marguerite Balland (1612-1707), fondatrice du monastère de la Visitation de Modène (1669) et directrice de conscience de Maria Beatrice d’Este, reine d'Angleterre, est une figure de proue dans le panorama féminin de l’époque de la Contre-Réforme. L’article reconstruit l’envergure de cette moniale ainsi que ses rapports avec la maison d’Este à travers des écrits qui la concernent (quelques pages tirées des Années Saintes, quelques lettres et surtout les deux biographies qui lui sont consacrées – l’une en français et l’autre en italien). Ces ouvrages biographiques sont fondés sur « le di lei memorie manoscritte », des textes fort probablement cachés à l’intérieur des archives du monastère visitandin de Modène, un riche et vaste réservoir de documents encore largement à explorer
Mechanical Characterization and Modeling of Glass Fiber-Reinforced Polyamide Built by Additive Manufacturing
No full textAdditive manufacturing (AM) is an emerging technology with the greatest potential impact on many engineering applications. Among the AM technologies, material extrusion is particularly interesting for plastic components due to its versatility and cost-effectiveness. There is, however, a limited knowledge of design methods to predict the mechanical strength of parts built by material extrusion. The materials are polymers, sometimes also reinforced, and deposited in layers like in laminated composites. Therefore, the mechanical behavior and strength can be characterized and modeled with methods already known for composite materials. Such tools are the classical lamination theory (CLT) and the failure criteria for composites. This paper addresses an analysis of a composite material made of long-fiber glass in a polyamide matrix built by additive manufacturing; in this relatively new technique, a continuous fiber is inserted between layers of polyamide deposited from a wire with a fused filament fabrication (FFF) 3D printer. The mechanical behavior was studied from tensile tests that were carried out to demonstrate the feasibility of modeling with the mentioned tools, and the material properties for predicting the stiffness and strength of components built with that technique were identified. The results show that the classical models for the mechanical behavior of composite materials are well-suited for this material to predict the influence of the main building parameters
Carotid artery atherosclerosis: mechanisms of instability and clinical implications
No full textCardiovascular disease remains a prominent cause of disability and premature death worldwide. Within this spectrum, carotid artery atherosclerosis is a complex and multifaceted condition, and a prominent precursor of acute ischaemic stroke and other cardiovascular events. The intricate interplay among inflammation, oxidative stress, endothelial dysfunction, lipid metabolism, and immune responses participates in the development of lesions, leading to luminal stenosis and potential plaque instability. Even non-stenotic plaques can precipitate a sudden cerebrovascular event, regardless of the degree of luminal encroachment. In this context, carotid imaging modalities have proved their efficacy in providing in vivo characterization of plaque features, contributing substantially to patient risk stratification and clinical management. This review emphasizes the importance of identifying high-risk individuals by use of current imaging modalities, biomarkers, and risk stratification tools. Such approaches inform early intervention and the implementation of personalized therapeutic strategies, ultimately enhancing patient outcomes in the realm of cardiovascular disease management
Le relazioni transatlantiche tra continuità e cambiamento: le crisi degli anni Settanta
No full textThis article deals with the relations between Europe and the United States during the 1970’s, demonstrating that they were characterized by moments of intense tensions, disagreements, and crises, reflecting the existence of different perspectives between the two sides of the Atlantic on economic and monetary issues, as well as on the process of détente and the Middle East. It will investigate the consequences of these transatlantic disagreements on the European integration process, showing that it was also thanks to the debate and confrontation with the United States, that the European Community made a qualitative leap, in its identity dimension, as demonstrated by the Declaration on European Identity adopted at the Copenhagen Summit in December 1973