Recent developments in nonsupersymmetric SO(10) unification

I review the recent efforts in the search for a minimal and predictive nonsupersymmetric SO(10) theory. The outcome is the revival of a minimal scenario in which an old result, claiming the incompatibility between unification constraints and symmetry-breaking dynamics, is now confuted by the implementation of the one-loop effective potential

Hygro-thermo-chemo-mechanical coupled discrete model for the self-healing in Ultra High Performance Concrete

Reliable durability predictions and design for advanced cement-based materials cannot disregard the modelling of their inherent self-healing capability. A discrete meso-scale model to simulate the recovery in water tightness, stiffness and strength induced by the (stimulated) autogenous healing of cracks for Ultra High Performance Concrete is presented. In this paper the model is implemented into the numerical framework of the Multiphysics-Lattice Discrete Particle Model (M-LDPM), resulting from the coupling of the Hygro-Thermo-Chemical (HTC) model and Lattice Discrete Particle Model (LDPM). Consistently with experimental evidence, the development of the self-repairing process is modelled as consisting of two independent stages: (a) the healing of matrix cracks, affecting both moisture permeability and fracture strength in the cracked state, and (b) the recovery in terms of fibre bridging action, relying on the adhesion between the healing products and the walls of the tunnel cracks which form during the fibre debonding process. This research activity is framed into the Horizon 2020 project ReSHEALience (GA 760824)

Numerical modelling via a coupled discrete approach of the autogenous healing for Fibre-Reinforced Cementitious Composites (FRCCs)

Aiming to predict long-term performance of advanced cement-based materials and design more durable structures, a reliable modelling of the autogenous healing of cementitious materials is crucial. A dis-crete model for the regain in terms of water tightness, stiffness and strength induced by the autogenous and/or “stimulate" autogenous healing was recently proposed for ordinary plain concrete. The modelling proposal stemmed from the coupling of two models, namely the Hygro-Thermo-Chemical (HTC) model, on one side,and the Lattice Discrete Particle Model (LDPM), on the other side, resulting in the Multiphysics-Lattice Discrete Particle Model (M-LDPM). Being this approach not customised only for ordinary concrete, but for the whole broad category of cementitious materials, in this paper, its application to Fibre-Reinforced Cementitious Composites is presented. To accurately simulate what has been experimentally observed so far, the mechanical model is updated to also include the self-healing of the tunnel cracks at the fibre-matrix interfaces. Therefore,the self-repairing process is modelled to develop on two independent stages: (a) matrix cracks healing, and(b) fibre bridging action restoring. This research activity is part of the modelling tasks framed into the project ReSHEALience, funded from the European Union’s Horizon 2020 Research and Innovation Programme

Combined effects of electromagnetic fields on immune and nervous responses.

In technologically developed countries, there is concern about hazards from electromagnetic fields (EMFs). Several studies have reported that immune and neuroendocrine systems exert an integrated response to EMF exposure. The aim of this review is to summarize the results of studies on the effect of low and high frequency EMF on immune and neuroendocrine systems on which our research group has been working for several years

Stellar evolution confronts axion models

Axion production from astrophysical bodies is a topic in continuous development, because of theoretical progress in the estimate of stellar emission rates and, especially, because of improved stellar observations. We carry out a comprehensive analysis of the most informative astrophysics data, revisiting the bounds on axion couplings to photons, nucleons and electrons, and reassessing the significance of various hints of anomalous stellar energy losses. We confront the performance of various theoretical constructions in accounting for these hints, while complying with the observational limits on axion couplings. We identify the most favorable models, and the regions in the mass/couplings parameter space which are preferred by the global fit. Finally, we scrutinize the discovery potential for such models at upcoming helioscopes, namely IAXO and its scaled versions

Modelling of autogenous healing for regular concrete via a discrete model

In this paper a numerical model for autogenous healing of normal strength concrete is presented in detail, along with preliminary results of its validation, which is planned to be achieved by comparing the results of numerical analyses with those of a dedicated experimental campaign. Recently the SMM (Solidification-Microprestress-Microplane model M4) model for concrete, which makes use of a modified microplane model M4 and the solidification-microprestress theory, has been extended to incorporate the autogenous healing effects. The moisture and heat fields, as well as the hydration degree, are obtained from the solution of a hygro-thermo-chemical problem, which is coupled with the SMM model. The updated model can also simulate the effects of cracking on the permeability and the restoring effect of the self-healing on the mechanical constitutive laws, i.e. the microplane model. In this work, the same approach is introduced into a discrete model, namely the Lattice Discrete Particle Model (LDPM). A numerical example is presented to validate the proposed computational model employing experimental data from a recent test series undertaken at Politecnico di Milano

On the vacuum of the minimal nonsupersymmetric SO(10) unification

We study a class of nonsupersymmetric SO(10) grand unified scenarios where the first stage of the symmetry breaking is driven by the vacuum expectation values of the 45-dimensional adjoint representation. Three decade old results claim that such a Higgs setting may lead exclusively to the flipped SU(5) x U(1) intermediate stage. We show that this conclusion is actually an artifact of the tree level potential. The study of the accidental global symmetries emerging in various limits of the scalar potential offers a simple understanding of the tree level result and a rationale for the drastic impact of quantum corrections. We scrutinize in detail the simplest and paradigmatic case of the 45_{H} + 16_{H} Higgs sector triggering the breaking of SO(10) to the standard electroweak model. We show that the minimization of the one-loop effective potential allows for intermediate SU(4)_C x SU(2)_L x U(1)_R and SU(3)_c x SU(2)_L x SU(2)_R x U(1)_{B-L} symmetric stages as well. These are the options favoured by gauge unification. Our results, that apply whenever the SO(10) breaking is triggered by , open the path for hunting the simplest realistic scenario of nonsupersymmetric SO(10) grand unification.Comment: 22 pages, 1 figure. Refs added. To appear in Phys. Rev.

Investigation of the Luco dei Marsi DSGSD revealing the first evidence of a basal shear zone in the central Apennine belt (Italy)

Deep-seated gravitational slope deformations (DSGSDs) show a wide range of geomorphological characteristics and kinematic behaviours. In many cases, deforming rock masses move on a continuous surface or a thick basal shear zone (BSZ) overlying the stable bedrock. The nature of this boundary is a significant issue in scientific debates since examples of BSZs have been observed or inferred in some DSGSDs worldwide. In the central Apennines, although several cases of DSGSDs have been described in recent decades, no evidence of BSZs has been documented thus far. This work presents the first case of a BSZ found in the region at the bottom of a large-scale gravitational deformation that affects the Mesozoic-Cenozoic carbonate ridge overhanging the Luco dei Marsi village (Abruzzi region). The BSZ consists of several metres-thick, cataclastic breccia developed within middle-Upper Cretaceous biodetritic limestone. The breccia level is exposed for approximately 200 m with a subhorizontal geometry and shows severe rock damage and weathering. The DSGSD hosting the BSZ affects an NNW-SSE-oriented and wide Miocene anticline whose eastern limb is dismembered by Pliocene-Quaternary normal faults delimiting the edge of a large Quaternary intermontane basin (the Fucino Basin). Field survey, aerial photointerpretation, and remote sensing (DInSAR technique) analyses outline an active gravity-driven process. This is characterized by several kinds of geomorphological features, including downhill- and uphill-facing scarps, ridge-top depressions, gravitational grabens and trenches in the upper and middle parts of the ridge, and bulging at the toe of the slope. These features, which can be distinguished from tectonic elements due to their shape and extension, are an indication of a high degree of internal deformation and a compound sagging geometry for the Luco dei Marsi DSGSD. The short-term activity of the process was revealed by DInSAR time series covering almost thirty years of satellite datasets, including ERS1/2, ENVISAT, COSMO-SkyMed, and SENTINEL 1 constellations. Strain rates on the order of a few mm/yr were inferred, with a marked difference between different sectors of the DSGSD area. The long-term (y > 102) lifespan of the DSGSD was framed into a multiple-step conceptual model summarizing the Early Pleistocene-Holocene geological evolution of the area. The model results outline the control exercised by extensional tectonics on DSGSD development, as progressive displacements along normal faults in the latest Pleistocene were the cause of lateral unconfinement at the toe of the slope. This work further contributes to the increasing knowledge on DSGSDs in the central Apennines and the understanding of the relationship between deformation features induced by slope morphogenesis, such as the BSZ, and Quaternary tectonics within the mountain belt

A Soil Parameters Geodatabase for the Modeling Assessment of Agricultural Conservation Practices Effects in the United States

Soil parameters for hydrology modeling in cropland dominated areas, from the regional to local scale, are part of critical biophysical information whose deficiency may increase the uncertainty of simulated conservation effects and predicting potential. Despite this importance, soil physical and hydraulic parameters lack common, wide-coverage repositories combined to digital maps as required by various hydrology-based agricultural water quality models. This paper describes the construction of a geoprocessing workflow and the resultant hydrology-structured soil hydraulic, physical, and chemical parameters geographic database for the entire United States, named US-SOILM-CEAP. This database is designed to store a-priori values for a suit of models, such as SWAT (Soil and Water Assessment Tool), APEX (Agricultural Policy Environmental EXtender) and ALMANAC (Agricultural Land Management Alternatives with Numerical Assessment Criteria), which are commonly used for the across scale assessment of agricultural hydrology and conservation practice scenarios. The Soil Survey Geographic (SSURGO) database developed by the U.S. Department of Agriculture provided the main source data for this development. Additional spatial information, a geographic information system platform and Python computer programming language code were used to create hydrology-based tile coverage of the areal soil units linked to the specific and detailed attributes required by each model. The created repository adds value to the source soil survey data, while maintaining and extending the detailed information necessary for the across scale and combined application of the models. Ultimately, our multi-model database provides a comprehensive product achieving joined informational-mapping-geoprocessing functionality with the explicit maintenance of the original conceptual links between soil series and composing soil layers, allowing for efficient data retrieval, analysis and service as input for modeling conservation effects