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Pension schemes versus real estate
The demographic, economic and social changes that have characterized the last decades, and the dramatic financial crisis that has taken place since 2008, have led to a demand for structural changes in the pension sector and a growing interest in individual pension products. Hence the need, for most elderly people, to liquidate their fixed assets, which are usually the homes in which they live. This highlights products such as reverse mortgages and domestic reversibility plans. Within this context, we propose a contractual scheme where an immediate life annuity is obtained by paying a single-premium in the form of real estate rights (RERs), for example by transferring to an insurer the property title of a house or a similar realty, while keeping its usufruct or a restricted bundle of rights. The level of the installments depends on the fair value of the transferred RER at the contractâs issue, the life expectancy of the insured and the expected growth rate of the real estate market value. The contract design is developed by considering the control of the financial risk inherent in the contract itself, because of the prospective changes in the value of the RERs, and the level of the insurerâs leverage. Finally, we provide some numerical evidence of the proposed contractual structure, in order to compare the level of the installments according to the house return forecasts in different European countries
Seismic retrofit of an existing RC building with isolation devices applied at base
Nowadays, seismic retrofit through isolation strategy represents a consolidated technique of protection against design earthquakes. This technique is also applied on existing structures extensively, due to the fact that it usually does not require any interruption of the building use and occupants evacuation. If applicable, it rapidly allows the seismically retrofitting of a building installed with seismic devices with low horizontal stiffness between the structure and the foundation decoupling, in fact, this allows the motion of the superstructure from the ground one. In this paper an application on an existing RC building of the seismic isolation is presented. The chosen building was built in the â90s only for vertical loads and realized without any detailing rule for structural ductility. The seismic retrofitting requirement stems from the fact that only recently, after the National seismic hazard maps update in 2003, the considered area has been upgraded to a medium-low seismic intensity zone, while at construction time no seismic classification was in existence by law. The case study peculiarity is that the seismic retrofitting has required an addition to seismic devices at the base, with related interventions such as the application of a bracing system consisting of two elastic steel frames. This intervention is required for stiffening the superstructure and, therefore, minimizing the higher vibration modes effects. The paper presents the main results obtained with a FEM model, implemented for simulating the initial and the design state when the interventions are considered. Finally, some results of non-linear dynamic time-history analyses are illustrated and commented for verifying superstructure elements and seismic devices
Numerical analysis on a reversible connection for steel modular buildings
Modular buildings are a new type of structural system composed by prefabricated modular units and assembled on site through inter-modular connections. These structures can form complete building blocks with suspended ceilings and installations, including electrical and water systems. These modular solutions can be adapted to any use like hospitals, housing schools, etc.
This work focuses on the analysis of structural behavior on a reversible steel connection modelling with finite element approach.
To this scope, in the paper an ideal case study is considered, characterized by steel elements.
The modules are assembled by inter-module connections that allow for rapid assembly onsite, without any need of skilled workmanship reducing the welding and the use of bolts. Therefore, Midas Fea NX is used to define the contact between steel elements in detail
Editorial: Recent Advances in Seismic Risk Assessment and Its Applications
This special issue discusses recent advances in seismic risk assessment with particular attention to the development and validation of new procedures that are capable of assessing failure modes and the fragility curves of existing buildings. The studies presented have also a probabilistic background, and show the importance of typological characteristics in the seismic response of a building. Furthermore, non-linear numerical analyses have confirmed the importance of implementing specific models in order to design appropriate interventions aimed at reducing the seismic risk of a specific construction
Mechanical and physical characterization of papercrete as new eco-friendly construction material
The manufacturing of Portland cement is responsible for a big amount of energy and greenhouse gas (GHG) emission. Therefore, to date, it is imperative to find alternative materials to replace a major part of cement for sustainable concrete constructions. The present study forms a part of an on-going research project on the application of new cementitious matrices produced using different types of recycled materials. In particular, it focuses on the use of pulp and waste paper to partially replace Portland cement at varying percentages for producing a new lightweight mortar, frequently named papercrete. The development of this economical and eco-friendly material may permit of recycling a big amount of waste paper leading to lower housing costs with also ecological benefits. To this scope, an experimental campaign in the laboratory is carried out to characterize this new innovative material from a physical and mechanical point of view. The preliminary results of this on-going experimental campaign are illustrated and commented on in this paper. The obtained results confirm the possibility of applying this partially-recycled material as a possible alternative for strengthening existing panels of masonry
On the dust and gas content of high-redshift galaxies hosting obscured AGN in the CDFâS
Submillimeter Galaxies (SMGs) at high redshift are among the best targets to investigate the early evolutionary phases in the lifetime of massive systems, during which large gas reservoirs sustain vigorous star formation and efficiently feed the central, buried Super Massive Black Hole (SMBH), until it enters into luminous Quasar (QSO) phase, quenching the star formation.
I present the analysis of new ALMA band 4 (1.8-2.4 mm) data of six obscured QSOs (log NH > 23) hosted by SMGs at redshift > 2.5 in the 7 Ms Chandra Deep Field South (CDF-S), showing their properties in terms of continuum dust emission and high-J CO transitions. Sizes and masses of the galaxies are measured to estimate whether and to which extent the host ISM may contribute to the nuclear absorption, assuming different geometries. The derived column densities suggest that the galaxy ISM can substantially contribute to the AGN obscuration. I also discuss the kinematics and morphology in some of these object, finding that two of the sources present unambiguous features of a rotating system, while a third source is possibly undergoing a merger
Frequency of the New HLA-B*2709 Allele in Ankylosing Spondylitis Patients and Healthy Individuals
We have recently described a new HLA-B27 subtype, named HLA-B*2709 (Del Porto et al. 1994). This allele is identical to the subtype most frequently found in Caucasoids, HLA-B*2705, except for a single amino acid substitution (Asp to His) in position 116. This residue, that is part of the F pocket of the molecule, has been shown to be relevant in determining which C-terminal amino acid of HLA-class I-binding peptides can be accomodated into the groove (Elliott, 1993). In nonamer peptides, this aminoacid corresponds to a primary anchor position (P9; Madden et al., 1992). Accordingly, we have previously shown that B2709 molecule hardly accepts nonamer peptides with an Arg or Tyr in P9, while the same amino acids represent good anchors for B2705 molecules (Fiorillo et al., 1995). Special attention is focused on HLA-B27 subtypes because of the strong association of B27 with ankylosing spondylitis (AS). More than 90% of AS patients are B27-positive and, conversely, about 4% of B27-positive individuals in the population are affected. This represents a relative risk over 100, that is the highest in HLA-disease associations. However, little is known on the pathogenic mechanisms of the disease. Following the hypothesis that an antigenic B27-binding peptide is involved in the disease (the so-called arthritogenic peptide), differential association with the different B27 subtypes may give a clue on the nature of such peptide. If two subtypes of partially overlapping peptide binding specificity are found to be both AS-associated, this would restrict the search for peptides that can be bound by both allelic products. Conversely, if a B27 subtype is found to be non AS-associated, this would be even more helpful in eliminating an array of peptides as possible candidates
PadrĂŁo de emergĂȘncia de ondas foliculares em protocolos longos (com ou sem troca de cidr) e efeito da estacionalidade em ovelhas Santa InĂȘs.
On the dust and gas content of high-redshift galaxies hosting obscured AGN in the CDFâS
Submillimeter Galaxies (SMGs) at high redshift are among the best targets to investigate the early evolutionary phases in the lifetime of massive systems, during which large gas reservoirs sustain vigorous star formation and efficiently feed the central, buried Super Massive Black Hole (SMBH), until it enters into luminous Quasar (QSO) phase, quenching the star formation.
I present the analysis of new ALMA band 4 (1.8-2.4 mm) data of six obscured QSOs (log NH > 23) hosted by SMGs at redshift > 2.5 in the 7 Ms Chandra Deep Field South (CDF-S), showing their properties in terms of continuum dust emission and high-J CO transitions. Sizes and masses of the galaxies are measured to estimate whether and to which extent the host ISM may contribute to the nuclear absorption, assuming different geometries. The derived column densities suggest that the galaxy ISM can substantially contribute to the AGN obscuration. I also discuss the kinematics and morphology in some of these object, finding that two of the sources present unambiguous features of a rotating system, while a third source is possibly undergoing a merger
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