Geometry and Stability of a Double-shell Dome in Four Building Phases: The Case Study of Santa Maria Alla Sanita in Naples

This research work provides a stability study for a double masonry dome during its construction process and, a consideration of the possible effects that the procedure followed for building the structure has on its current mechanical behaviour. In particular, the analysis is carried out on the Baroque dome of Santa Maria alla Sanita in Naples, a relatively small dome with a span of 12 m. The main contribution of the paper consists of making a hypothesis about the different phases of construction and demonstrating that the dome was in equilibrium during these different phases. This aspect has been rarely considered when analysing historical structures. The theoretical framework assumed refers to Limit Analysis in which the masonry is modelled as composed of rigid-unilateral material. To assess the stability of the dome, the study proposes an equilibrium analysis performed both graphically and analytically, by using the graphic statics and the membrane analysis. The results obtained from the two methods are also compared, at each stage of construction. Besides the classical graphical methodology based on the slicing technique, the membrane equilibrium solution provides a wider repertoire of equilibrium states, since it allows for biaxial stress fields and is here implemented with a new method for which the surface and the stress potential are both approximated through simplicial surfaces based on the same triangulation. This more refined analysis confirms the results obtained through graphic statics giving wider geometrical safety margins and a more detailed interpretation of the non-axisymmetric loading case

Graphical and Analytical Quantitative Comparison in the Domes Assessment: The Case of San Francesco di Paola

(1) Methods for checking the condition of monumental masonry structures can still be considered understudied. Among the different approaches available in the literature, the graphical ones have a special role, due to their simplicity and effectiveness. (2) In this work, a 2D method (Thrust Line Analysis (TLA)), the Modified Thrust Line Method (MTLM), and the 3D Membrane Equilibrium Analysis (MEA) method are compared. All methods have the same starting concept: no tensile strength, no sliding between the stone blocks, infinite compressive strength. (3) The methods are compared in terms of stress distribution (for the same—or similar—thrust line), and in terms of the Geometrical Safety Factor ensured. (4) The work shows that these theories if properly conveyed in a scientific methodology (as many authors are doing currently and have done in the past) demonstrate the effectiveness and the advantages of graphical methods for simple structures

Considerations about the static response of masonry domes: a comparison between limit analysis and finite element method

Masonry domes constitute a large part of the international architectural heritage. The issue of its conservation has long been a challenge both for architects and engineers. To limit any problems related to degradation, arising from structural damage or external factors, historical buildings are continuously restored and strengthened. Reliable tools are therefore needed to assess their structural safety. The present work discusses how modern methods can be used to understand ancient structures addressing the comparison between different methods of structural analysis, exploring the range of applications of limit analysis and finite element analysis in the stability assessment of masonry domes, focusing on the pros and cons of each approach. By applying equilibrium approaches and deformation-based models (finite element method), this paper provides two demonstration examples to compare the utility of each of them within a longstanding debate on the most proper way to evaluate traditional structures in masonry

Considerations about the static response of masonry domes: a comparison between limit analysis and finite element method

Masonry domes constitute a large part of the international architectural heritage. The issue of its conservation has long been a challenge both for architects and engineers. To limit any problems related to degradation, arising from structural damage or external factors, historical buildings are continuously restored and strengthened. Reliable tools are therefore needed to assess their structural safety. The present work discusses how modern methods can be used to understand ancient structures addressing the comparison between different methods of structural analysis, exploring the range of applications of limit analysis and finite element analysis in the stability assessment of masonry domes, focusing on the pros and cons of each approach. By applying equilibrium approaches and deformation-based models (finite element method), this paper provides two demonstration examples to compare the utility of each of them within a longstanding debate on the most proper way to evaluate traditional structures in masonry

A novel telomerase activity and microRNA-21 upregulation identified in a family with palmoplantar keratoderma

Palmoplantar keratoderma is a set of skin diseases with hyperkeratotic thickening of palms and soles which are characteristic of these heterogeneous group of keratinization disorders. Various genetic mutations, autosomal dominant or recessive, have been identified which may triggerpalmoplantar keratoderma, as KRT9 (Keratin 9), KRT1 (Keratin1), AQP5 (Aquaporin), SERPINB 7 (serine protease inhibitor). The identification of causal mutations is extremely important for the correct diagnosis. Here, we report the case of a family affected from Palmoplantar keratoderma caused by autosomal dominant KRT1 mutations (Unna-Thost disease). Telomerase activation and hTERT expression take a part in the process of cell proliferation and inflammation and microRNAs, as microRNA-21, are emerging as drivers in the regulation of telomerase activity. Here, the patients underwent KRT1 analysis genetic sequence, telomerase activity and miR-21 expression. Beside histopathology assay was performed. The patients presented thickening of the skin on soles of the feet and the palms of the hands, KRT1mutations and showed high expression levels of hTERT and hTR, the gene encoding for the telomeric subunits, and miR-21 (fold change > 1.5 and p value = 0.043), explicating the aberrant proliferation of epidermal layer and the inflammatory state characterizing palmoplantar keratoderma

Exploring Circulating Long Non-Coding RNAs in Mild Cognitive Impairment Patients’ Blood

Mild cognitive impairment (MCI) is a transitional clinical stage prior to dementia. Patients with amnestic MCI have a high risk of progression toward Alzheimer’s disease. Both amnestic mild cognitive impairment and sporadic Alzheimer’s disease are multifactorial disorders consequential from a multifaceted cross-talk among molecular and biological processes. Non-coding RNAs play an important role in the regulation of gene expression, mainly long non-coding RNAs (lncRNAs), that regulate other RNA transcripts through binding microRNAs. Cross-talk between RNAs, including coding RNAs and non-coding RNAs, produces a significant regulatory network all through the transcriptome. The relationship of genes and non-coding RNAs could improve the knowledge of the genetic factors contributing to the predisposition and pathophysiology of MCI. The objective of this study was to identify the expression patterns and relevant lncRNA-associated miRNA regulatory axes in the blood of MCI patients, which includes lncRNA-SNHG16, lncRNA-H19, and lncRNA-NEAT1. Microarray investigations have demonstrated modifications in the expression of long non-coding RNAs (lncRNA) in the blood of patients with MCI compared with control samples. This is the first study to explore lncRNA profiles in mild cognitive impairment blood. Our study proposes RNAs targets involved in molecular pathways connected to the pathogenesis of MCI