186698 research outputs found
Sort by
Leveraging Additive Manufacturing in Industry to Create Enhanced-Performance Components
No full textAM technology enables the production of complex structures layer-by-layer, thus transforming traditional manufacturing methods and offering unprecedented design freedom and material efficiency. This research aims to bridge the gap between AM's theoretical capabilities and practical applications in the robotic and industrial fields, where AM can reduce mechanical complexity, optimise performance, and increase part reliability. In particular, the potential of additive manufacturing (AM) in robotics is explored, focusing on two key innovations: monolithic mechanisms with compliant joints and non-planar additive manufacturing.
Monolithic mechanisms, manufactured as single, integrated parts, eliminate the need for assembly and increase the durability of robotic components. Compliant joints within these mechanisms enable movement through elastic deformation of the part itself, enhancing their robustness and reducing the need for maintenance.
Non-planar AM further contributes to this field by allowing 3D layer paths, minimising the staircase effect and enhancing the surface quality and practical performances.
First, this thesis provides a detailed review of the current state of monolithic mechanisms with compliant joints and the advances in non-planar additive manufacturing.
In pursuit of practical applications, this work presents the design and development of two additively manufactured monolithic robotic components: a compliant joint gripper and a robot with delta kinematics. These designs showcase the benefits of AM in producing simple, efficient, and lightweight components tailored for industrial applications.
Furthermore, the thesis introduces an innovative slicing algorithm for non-planar AM designed for desktop machines. This new slicing methodology optimises layer orientation along curved paths, improving part surface finish through slices from the intersection with the model to be printed to accurately reproduce the model top surfaces while avoiding collisions.
By integrating advanced design and manufacturing techniques, this thesis demonstrates AM's transformative impact on robotic design, potentially redefining standards in high-performance, customised parts in robotic and industrial fields
The Effectiveness and Complication Rate of Resorbable Biopolymers in Oral Surgery: A Systematic Review
No full textSearch for same-charge top-quark pair production in pp collisions at sqrt(s) = 13 TeV with the ATLAS detector
No full textA search for the production of top-quark pairs with the same electric charge (tt or (tt) over bar) is presented. The analysis uses proton-proton collision data at root s = 13 TeV, recorded by the ATLAS detector at the Large Hadron Collider, corresponding to an integrated luminosity of 140 fb(-1). Events with two same-charge leptons and at least two b-tagged jets are selected. Neural networks are employed to define two selections sensitive to additional couplings beyond the Standard Model that would enhance the production rate of same-sign top-quark pairs. No significant signal is observed, leading to an upper limit on the total production cross-section of same-sign top-quark pairs of 1.6 fb at 95% confidence level. Corresponding limits on the three Wilson coefficients associated with the O-tu((1)), O-Qu((1)), and O-Qu((8)) operators in the Standard Model Effective Field Theory framework are derived
Lipidomic Transitions and Neurodevelopmental Implications in Preterm Neonates Born Before 32 Weeks Gestational Age: A Prospective, Single-Center Study Integrated with Brain MRI Data
No full textAbstract
Background: Prematurity is a major cause of neonatal morbidity and mortality, with infants born before 32 weeks of gestation at high risk for neurological and metabolic complications. Lipids play a fundamental role in neonatal development, particularly in brain maturation, pulmonary function, and energy metabolism, yet lipidomic alterations in preterm neonates remain largely unexplored.
Objectives: This study aimed to characterize lipidomic transitions in preterm neonates (<32 weeks gestation) and investigate their associations with key clinical outcomes, including brain injury and mechanical ventilation. We hypothesized that specific lipidomic profiles could serve as potential biomarkers for neonatal complications and neurodevelopmental trajectories.
Methods: A prospective, single-center study was conducted at IRCCS Giannina Gaslini Hospital, enrolling preterm neonates (24+0 to 31+6 weeks gestation). Lipidomic profiling was performed at five time points from birth to term-equivalent age (TEA), integrating liquid chromatography-mass spectrometry (LC-MS) and Weighted Gene Co-expression Network Analysis (WGCNA) to identify lipid clusters associated with neonatal morbidities. Pathway enrichment analysis was conducted using MetaboAnalyst.
Results: After quality control, 81 out of 103 neonates were included in the analysis. Key findings showed that diacylglycerols (DG), phosphatidylcholines, lysophosphatidylcholines, sphingomyelins, and triglycerides were enriched in neonates with germinal matrix-intraventricular hemorrhage (GMH-IVH) (r = 0.22, p = 0.001). DG levels had a weak but significant negative correlation with mechanical ventilation (r = -0.21, p = 0.001). A metabolic trajectory was observed from birth (T0) to term-equivalent age (TEA), shifting from an oxidative state at birth to a more regulated, neuroprotective environment at TEA. The increase in oligodendrocyte differentiation pathways from 32 weeks of gestation onward highlights accelerated myelination within the central nervous system.
Conclusion: This study highlights lipidomic changes in preterm neonates, particularly regarding brain injury and mechanical ventilation, suggesting metabolic adaptations tied to vascular stability, neuroinflammation, and pulmonary function. The lipid profile shift from placental dependence to endogenous regulation emphasizes the roles of beta-oxidation, sphingolipid metabolism, and myelination. Optimizing nutrition, including lipid supplementation and metabolic support, may improve neurodevelopmental outcomes. Integrating lipidomics into neonatal care could enhance biomarker discovery and targeted interventions, ultimately improving long-term outcomes for preterm infants
Projective synthesis of planar compliant mechanisms
No full textIn this paper, a novel method for the synthesis of planar compliant mechanisms, based on projective geometry, is presented. The projective synthesis method exploits the antiprojective polarity in the weighted projective plane, enabling the extension of single-point to single-body relations. The method consists of a top-down procedure that, starting from the load–displacement requirements, defines the elastic suspension as a system of substructures in series and parallel arrangements, according to the prescribed topology. The geometric decomposition intrinsically guarantees positive definiteness of the kinetostatic relations at any level. Multiple solutions to the synthesis problem can be generated. The method has been implemented to the synthesis of compliant mechanisms with open and closed chains, and numerical simulations have been performed to validate the theoretical model
Neuroradiologic, Clinical, and Genetic Characterization of Cerebellar Heterotopia: A Pediatric Multicentric Study.
No full text
Long-Acting Antibiotics: New Opportunities Beyond Acute Bacterial Skin and Skin Structure Infections (ABSSSIs)!
No full text: Currently, two long-acting antibiotics are available: oritavancin (ORI) and dalbavancin (DBV) [...]
Sesterterpenoids: sources, structural diversity, biological activity, and data management
No full textReviewing the literature published up to October 2024.Sesterterpenoids are one of the most chemically diverse and biologically promising subgroup of terpenoids, the largest family of secondary metabolites. The present review article summarizes more than seven decades of studies on isolation and characterization of more than 1600 structurally novel sesterterpenoids, supplemented by biological, pharmacological, ecological, and geographic distribution data. All the information have been implemented in eight tables available on the web and a relational database https://sesterterpenoids.unige.net/. The interface has two sections, one open to the public for reading only and the other, protected by an authentication mechanism, for timely updating of published results
Seismic fragility assessment of existing masonry buildings in aggregate located in Zagreb
No full textThe historic center of Zagreb's Lower Town presents a moderate seismic hazard but high exposure and vulnerability. This vulnerability was also demonstrated by the earthquake that struck Zagreb on March 22, 2020 (ML=5.5), which led to significant socio-economic repercussions and damage to the historic buildings. The paper analyses the residential buildings in Zagreb's historic downtown and aims to develop tools useful for urban-scale seismic risk assessment. To this end, the seismic response of unreinforced masonry (URM) buildings in aggregate representing the city's construction was numerically analyzed using the equivalent frame approach implemented in Tremuri software. Special attention was given to evaluating the aggregate effect by analyzing the Structural Unit (SU) both in isolation and aggregate configurations. Another aspect analyzed is the evaluation of out-of-plane (OOP) mechanisms and how they impact the development of global fragility curves. The analysis of local mechanisms was carried out using the rigid block model assumptions, with seismic input from accelerograms derived from the 3D model. For this purpose, a detailed analysis was conducted on the structure's dynamic response variation with increasing damage and on the related floor spectra. For the reference building, it was found that the aggregate effect is beneficial for the single SU, while the OOP mechanisms lead to a considerable setback of the fragility curves due to the reduced in-plane (IP) vulnerability of the building, and thus the lack of a filtering effect by the structure