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High energy gamma-rays from the 116Sn + 24Mg reaction at 23A MeV were measured using the MEDEA detector at LNS – INFN Catania. Combining this new data with previous measurements yields a detailed view of the quenching of the Giant Dipole Resonance as a function of excitation energy in nuclei of mass A in the range 120÷132. The transition towards the disappearance of the dipole strength, which occurs around 230 MeV excitation energy, appears to be remarkably sharp. Current phenomenological models give qualitative explanations for the quenching but cannot reproduce its detailed features. Keywords: Giant Dipole Resonance, Hot nuclei, Fusion reactions, Statistical Model

We investigate unprecedented experimental information on the fusion reaction induced by the radioactive projectile 8Li on a 4He gas target, at center-of-mass energies between 0.6 and 5 MeV. The main issue is the tendency of the dimensionless fusion cross section σfπƛ2 to form well visible plateaus alternated to steep rises. This finding is likely to be the most genuine consequence of the discrete nature of the intervening angular momenta observed so far in fusion reactions right above the Coulomb barrier. A partial-wave analysis, exclusively based on a pure quantal penetration fusion model and sensitive to the interaction potential, identifies a remarkably low-height barrier.

Abstract Background Metabolic dysfunction-associated Steatotic Liver Disease (MASLD) displays a worse prognosis in subjects with type 2 diabetes (T2D); effective treatments are, so far, scanty. Semaglutide showed efficacy in improving steatohepatitis. We longitudinally observed a MASLD cohort of T2D subjects starting semaglutide, to detect an improvement of non-invasive surrogates of steatosis and fibro-inflammatory liver involvement, evaluating the role of mild alcohol consumption. Patients and methods In 62 overweight/obese T2D subjects with MASLD (36 non-drinker and 26 mild alcohol consumers), anthropometric, bio-humoral and transient elastography (TE) data were collected before (T0) and after an average time of 6.4 month (T1) from injective semaglutide prescription. Circulating levels of hormones (GIP, GLP-1, glucagon, insulin) and inflammatory markers (TNFα, MCP-1, IL-18, IL-10) were measured. Steatotic and necro-inflammatory liver involvement was evaluated with FibroScan controlled attenuation parameter (CAP) and liver stiffness (LS), respectively. Results Significant (p

It is nowadays recognized that the building sector causes the greatest environmental impact in terms of both waste production and carbon emissions. Within the context of ecologically sustainable development (ESD), the construction sector is looking for more eco-friendly materials, such as natural fibres. Natural fibers are worldwide recognized as ideal replacement for traditional construction materials, providing excellent thermal and acoustic insulation for building but also for adoption as reinforcement fibers in cement mortars, composite materials, solid boards/panels, raw biomasses, multi-layers, filled loosen/foaming types, particles, slurry types, coils, bricks, etc. The aim of this work is to provide a clear overview on the natural fibers currently employed in the green production of building components, with the main focus on wool fibers deriving from the livestock sector, where wool waste disposal is a crucial problem. This article is a review conducted using the Systematic Literature Review (SLR) approach, a globally recognized method that is not inherently innovative. The innovation of this article lies in the addressed topic, which is relatively new and has only recently gained significant attention, resulting in a limited number of highly relevant articles in the literature.A systematic literature review of the use of wool fibers for green building components is conducted herein to highlight the characteristics that make such material a usable resource in the construction sector and the limits of its use. Given the findings from the reviewed papers, the authors could document that most of the reviewed articles aimed at analyzing the mechanical, thermal, and acoustic properties of building components containing wool fibres. The review highlights that the strength of the wool fiber relies on its thermal properties which can be exploited for building thermal insulation. The wool fiber is also featured to provide good resistance to flexural loads; conversely, all the studies highlighted a negative effect of wool fibers on the compressive behavior of the investigated building components. The analysis of the acoustic properties showed that given the strong capacity of the wool fiber to absorb sound, wool is a great alternative to the conventional materials derived from non-renewable resources.Nevertheless, despite the eligibility of such fiber to be employed soon in the building sector, the analysis about the economic viability of the manufacturing process suggests that the high costs for the raw material, labor, electricity, and above all the high volume of water have to be drastically reduced by prompting the development of sheep wool fiber waterless processing. The achieved results could represent a first step in planning the sustainable re-use of wool waste as natural, renewable, and biodegradable fiber in the construction sector, providing the possibility of creating a new supply chain and solving the problem of its disposal.

Abstract Currently available performance-based methodologies for assessing the fragility of structures subjected to tsunami neglect the effects of tsunami-induced vertical loads due to internal buoyancy. This paper adopts a generalized methodology for the performance assessment of structures that integrates the effects of buoyancy loads on interior slabs during a tsunami inundation. The methodology is applied in the fragility assessment of three case-study frames (low, mid and high-rise), representative of existing masonry-infilled reinforced concrete (RC) buildings typical of Mediterranean region. The paper shows the effect of modelling buoyancy loads on damage evolution and fragility curves associated with different structural damage mechanisms for existing RC frames with breakaway infill walls including consideration of blow-out slabs. The outcomes attest that buoyancy loads affect the damage assessment of buildings during a tsunami, especially in the case of mid and high-rise structures with blow-out slabs. The rate of occurrence of slabs uplift failure increases with the number of stories of the building, indicating the need to account for such damage mechanism when assessing the performance of structures. It is also found that buoyancy loads slightly affect the fragility curves associated to other structural damage mechanisms for existing RC buildings commonly monitored for fragility assessment.

The 2004 Indian Ocean tsunami affected 5% of Sri Lanka’s schools, severely damaging 108 and destroying 74. The catastrophe highlighted the critical role of schools in providing educational continuity during community recovery. Sri Lanka has since rehabilitated and rebuilt most of the destroyed schools along the coastline. However, there is a limited understanding of current levels of school exposure to tsunami. This hampers preparedness and risk reduction interventions that can improve community and educational tsunami resilience. This paper presents a multi-disciplinary school exposure database relevant to both vulnerability and loss modelling. The repository includes data on 38 schools and 86 classroom buildings, surveyed across the coastal districts of Ampara, Batticaloa and Galle in Sri Lanka, which were heavily affected by the 2004 tsunami. A new engineering rapid visual survey tool is presented that was used to conduct the physical assessment of schools for the exposure repository. School damage mechanisms observed in past tsunami inform the survey forms, which are designed to capture information at both school compound and building levels. The tsunami engineering survey tools are universally applicable for the visual assessment of schools exposed to tsunami. The surveys show that most Sri Lankan school buildings can be classified into three building archetypes. This means that future risk assessments can be conducted considering a small number of index buildings that are based on these archetypes with differing partition arrangements and structural health conditions. The surveys also raise three significant concerns. Firstly, most schools affected by the 2004 tsunami remain in the same exposed locations without any consideration for tsunami design or strengthening provisions. Secondly, Sri Lankan schools are fragile to tsunami loading and many of the schools in the Galle district suffer from severe corrosion, which will further affect their tsunami vulnerability. Thirdly, schools do not appear prepared for tsunami, and do not have adequate tsunami warnings nor evacuation protocols in place. These observations raise the urgent need to mitigate tsunami risk, including a holistic plan for tsunami retrofitting and for interventions to improve the tsunami preparedness of schools in Sri Lanka.

A theoretical approach based on Periodic Boundary Conditions (PBC) and a Linear Combination of Atomic Orbitals (LCAO) in the framework of the density functional theory (DFT) is used to investigate the molecular mechanism that rules the piezoelectric behavior of poly(vinylidene fluoride) (PVDF) polymer in the crystalline β-phase. We present several computational tests highlighting the peculiar electrostatic potential energy landscape the polymer chains feel when they change their orientation by a rigid rotation in the lattice cell. We demonstrate that a rotation of the permanent dipole through chain rotation has a rather low energy cost and leads to a lattice relaxation. This justifies the macroscopic strain observed when the material is subjected to an electric field. Moreover, we investigate the effect on the molecular geometry of the expansion of the lattice parameters in the (a, b) plane, proving that the rotation of the dipole can take place spontaneously under mechanical deformation. By band deconvolution of the IR and Raman spectra of a PVDF film with a high content of β-phase, we provide the experimental phonon wavenumbers and relative band intensities, which we compare against the predictions from DFT calculations. This analysis shows the reliability of the LCAO approach, as implemented in the CRYSTAL software, for calculating the vibrational spectra. Finally, we investigate how the IR/Raman spectra evolve as a function of inter-chain distance, moving towards the isolated chain limit and to the limit of a single crystal slab. The results show the relevance of the inter-molecular interactions on the vibrational dynamics and on the electro-optical features ruling the intensity pattern of the vibrational spectra.

To assess the health condition of structures and infrastructure during their service lives, continuous vibration-based monitoring represents a viable and cost-effective solution. Model updating and digital twins are increasingly adopted for damage detection. However, significant gaps and uncertainties in damage quantification still arise. This work presents original data from output-only modal identification tests on full-scale, two-storey reinforced concrete (RC) frames subjected to pseudo-dynamic loading to simulate seismic damage. The frames are tested with two masonry infill wall configurations with three-sided and four-sided boundary conditions, and the observed seismic damage is correlated to a damage scale. Output-only modal identification tests are performed before and after testing to catch variations in modal properties due to observed damage. Experimental data are used to build a refined finite element model able to reliably simulate the static and dynamic performance of the infilled RC frames before and after damage. The model allowed for the further assessment of the variation in natural frequencies of tested specimens at different earthquake intensities, the correlation of such variations to damage levels, and identification of the contribution of structural and non-structural components to the overall frequency variation.

Las Kürzestgeschichten constan en la literatura alemana desde hace muchas décadas, procediendo de géneros muy difundidos, sea en la literatura alta sea en la popular (anécdota, Kalendergeschichte). A comienzos del s. XX su forma se va caracterizando en el sentido de la expresión de una postura o protesta política. Al acabar la Segunda Guerra Mundial, muchos autores de microrrelatos se alejan en sus textos del realismo que se consideraba necesario para encarar la reconstrucción, desarrollando un estilo más subjetivo que se acerca a ciertos rasgos de la literatura expresionista. Un estilo de carácter más psicológico, tanto en el empleo del punto de vista como en los asuntos y temas. Entre los autores más interesantes de los años Sesenta y Setenta, Günter Kunert, Helmut Heissebüttel, Wolfdietrich Schnurre, Günter Bruno Fuchs. Peter Bichsel, Ror Wolf, Adelheid Duvanel, Urs Widmer son algunos de los mejores autores que privilegian este género para expresar el disagio y la ironía de la condición humana. El carácter más libre y la posibilidad de experimentar hacen del microrrelato un género adecuado a la deconstrucción de categorías y esquemas socioculturales, por lo que se puede definir como el género del compromiso por excelencia. Su tendencia a desconcertar y a no confortar el lector se vuelve un mensaje poderoso contra la homologación y la falta de conciencia.