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Cuprate superconductors have long been thought of as having strong electronic correlations but negligible spin-orbit coupling. Using spin- and angle-resolved photoemission spectroscopy, we discovered that one of the most studied cuprate superconductors, Bi2212, has a nontrivial spin texture with a spin-momentum locking that circles the Brillouin zone center and a spin-layer locking that allows states of opposite spin to be localized in different parts of the unit cell. Our findings pose challenges for the vast majority of models of cuprates, such as the Hubbard model and its variants, where spin-orbit interaction has been mostly neglected, and open the intriguing question of how the high-temperature superconducting state emerges in the presence of this nontrivial spin texture.

Understanding the fine interplay between spin and orbital degrees of freedom in the surface states of topological insulators is the key to the development of next-generation spintronics devices. So far, the majority of studies have focused on the helical spin texture of the topologically protected surface state (TSS) and little attention has been devoted to the spin texture of the other surface states: the bulk-originated quantum well states (QWSs). This paper presents such study in a prototypical topological insulator, Bi2Se3. By using spin- and angle-resolved photoemission spectroscopy, we reveal a full momentum-dependent spin texture of the QWSs and their response to light polarization. We find that these states share a similar spin-orbital texture with the TSS. This paper shows an intimate correlation between the surface and bulk states, which was overseen before, and provides relevant information to understand how the surface states evolve with the bulk states.

The automatic generation of structured 3D model from point clouds is a primary focus for a lot of researches in the area of 3D modelling and HBIM. The use of procedural modelling techniques, based on set of geometric rules, is spreading the construction of parametric objects and processes for survey data mapping. In this research field one of the most common methodological approach consists in testing different procedures based on use of specific data from point cloud. One of the main problem to solve is to define the best parameters to use in relation to geometric features of different architectural element and what are the data to extract from point cloud. Starting from shape grammar approach, the main goal of our research is to define 3D parametric models for ribbed vaults suitable to generate 3D smart model for different uses. Most researches in this area deal the case of rectangular or square plan vaults, we addressed the case of trapezoidal vaults and different rules used for apsidal vaults tracing. Our aim is to define an adaptive parametric model that we can use to generate a 3D ideal model or a mixed reality based model. In order to evaluate our tool we compared two 3D models with point clouds: the first is based on geometric rules from sources, the second is based on some specific data from point cloud. Testing the tool on two gothic churches in Naples, the church of S. Lorenzo and the church of S.Maria di Donnaregina, we are going to improve it.

This article analyzes the value of truth in postmodern societies and discusses how truth becomes abstract or of little importance. The study discusses the challenges faced by citizenship and how public spaces are being threatened by new technologies and media. In times of misinformation, how communication influences the exercise of citizenship and, specifically, the vote and the implementation of policies. Ignorance and information, are put together with powerful manipulative structures rooted in technological instruments. The "post-truth" emerges as the wildcard concept to understand the dynamics that plague democracies. The study is based in exploratory and bibliographic research and concludes that reflection is needed on what kind of democracy is unveiled and what are democratic instruments capable of overlooking the absence of neutrality and media impartiality.

We have measured the signatures of electronic energy scales and their doping evolution in the band structure of (Sr1-xLax)3Ir2O7 using angle-resolved photoemission spectroscopy. While band splittings and positions corresponding to the bilayer splitting and spin-orbit coupling undergo only small changes, the Mott gap and effective mass of both the lower Hubbard band and conduction band exhibit strong variations with doping. These changes correspond to similar observations in the cuprate superconductors, and are likely connected to the changing effective Coulomb interaction upon addition of itinerant carriers.

The ability to probe symmetry-breaking transitions on their natural time scales is one of the key challenges in nonequilibrium physics. Stripe ordering represents an intriguing type of broken symmetry, where complex interactions result in atomic-scale lines of charge and spin density. Although phonon anomalies and periodic distortions attest the importance of electron-phonon coupling in the formation of stripe phases, a direct time-domain view of vibrational symmetry breaking is lacking. We report experiments that track the transient multi-terahertz response of the model stripe compound La1.75Sr0.25NiO4, yielding novel insight into its electronic and structural dynamics following an ultrafast optical quench. We find that although electronic carriers are immediately delocalized, the crystal symmetry remains initially frozen-as witnessed by time-delayed suppression of zone-folded Ni-O bending modes acting as a fingerprint of lattice symmetry. Longitudinal and transverse vibrations react with different speeds, indicating a strong directionality and an important role of polar interactions. The hidden complexity of electronic and structural coupling during stripe melting and formation, captured here within a single terahertz spectrum, opens new paths to understanding symmetry-breaking dynamics in solids.

The epidemic spread of childhood obesity in Western society has interested many researchers, who agree in defining it as a multifactorial disease in which not only eating habits and sedentary lifestyle play a role, but also genetic predisposition. The aim of this study was to analyze the personality profile of a group of mothers of children with obesity and to compare this profile to that of a group of mothers of children without obesity. A total of 258 mothers participated in the study (126 mothers of children with obesity and 132 mothers of children without obesity). Weight and height were measured and the body mass index was calculated. The Minnesota Multiphasic Personality Inventory second edition (MMPI-2), evaluating personality and psychological disorders, was used to evaluate the personality profile. The results suggested that mothers of children with obesity score higher than the mothers of children without obesity in all MMPI-2 subscales. In most of these subscales, the differences between the two groups of mothers were statistically significant and with a medium to high effect size. These data suggest a new perspective on childhood obesity, identifying it as a multifactorial pathology that requires a multimodal and multidisciplinary approach that also takes care of caregivers to ensure optimal therapeutic efficacy.

The paper presents the results of an experimental research activity aimed to individuate digital tools for an intelligent mapping of structural and material decay of historical buildings.The activities carried out are part of the context of Scan-to-BIM processes, as they establish a workflow that, starting from 3D survey data, leads to an information model enriched by information related to the conservation state of surfaces and to the structural characteristics of the real building. The experimentation has been performed with the support of a software house, looking forward to turning this workflow into an actual implementation on a BIM software. In this regard, this research becomes part of the context of the studies concerned in the digital management processes of the historical built heritage, setting and testing specific parametrical objects that add to H-BIM models the possibility of documenting and sharing graphical, numerical and descriptive data of decay phenomena and, through integrative information sheets, damage phenomena.

This paper presents a part from one broader research project on ribbed vaults. The main goal is to generate a parametric objects library for ribbed vaults, suitable both for HBIM system, for structural analysis or for Cultural Heritage dissemination. Starting from Treatises study we have analyzed different classification system and different terminology used for ribbed vaults components in different languages, especially in English, French, Spanish and Italian, our aim is to improve a multilingual vocabularies. In our research we have defined an experimental workflow to generate a set of ribbed vaults library based on the geometric rules from treatises and a controlled vocabulary, the comparison of these 3D models with point clouds allows us to identify the rule used or to define a new rule and, therefore, to build complex parametric models based on reality-based surveys. We are improving our parametric model using different geometric rules from Spanish, French and English manuals. We can generate the realty based model using the same parametric model, in this case the input data is the ribs geometry extracted from the point cloud. We use a generative tool to analyze the curves from point cloud and to draw the borders. We are going to test our tool on some case studies for historical architectural elements indexing, for geometries reconstruction in HBIM environment and for point cloud segmentation in DL process.

Background: This cohort study aimed to explore whether and to what extent alexithymia would be associated with cardiovascular disease (CVD) risk over an estimated 10-year period, over and above established clinical cofactors (i.e., depressive symptoms, quality of life, sociodemographic, anthropometric, lifestyle, and biological data), in a low-risk population of blood donors. Methods: A sample of 1,021 adult Italian blood donors (age 46.9 ± 8.39; 61.2% men) was consecutively recruited. The 10-year-CVD risk score was estimated using the CUORE risk score (CRS). Sociodemographic, lifestyle, anthropometric, biological, and psychological (i.e., quality of life, depressive symptoms, and alexithymia) CVD risk data were assessed using validated self-report measures or clinical records. Results: As expected, most participants (78.5%) had a low CVD risk (CRS < 3%) and an overall low-risk profile for all the parameters. Compared with subjects at low risk of CVD (n = 911, 78.5%), those with high risk (i.e., rated ≥3 on CUORE risk assessment; n = 250, 21.5%) reported higher levels of alexithymia (p < 0.001). Subjects with higher alexithymia (n = 236, 23.1%) reported higher levels of psychosocial impairment, depressive symptoms, and biological risk variables for CVD. Alexithymia was significantly associated with 10-year CVD risk (OR = 1.02, 95% CI = 1.01–1.04, p = 0.009), even after adjusting for key sociodemographic and clinical risk variables. Conclusion: Although limited by the cross-sectional design, this study is the first to show that alexithymia leads to a higher risk for 10-year CVD estimate in healthy subjects with low-risk profile, regardless of known biomarkers and traditional CVD risk factors. [ABSTRACT FROM AUTHOR]

In this paper, we consider a linear elliptic operator E with real constant coefficients of order 2m in two independent variables without lower order terms. For this equation, we consider linear BVPs in which the boundary operators T1, . . ., Tm are of ordermand satisfy the Lopatinskii-Shapiro condition with respect to E. We prove boundary completeness properties for the system {(T1ωk, . . ., Tmωk)}, where {ωk} is a system of polynomial solutions of the equation Eu = 0. [ABSTRACT FROM AUTHOR]

Chronic pain, with its complex and multidimensional nature, poses significant challenges in identifying effective long‐term treatments. There is growing scientific interest in how psychopathological and personality dimensions may influence the maintenance and development of chronic pain. This longitudinal study aimed to investigate whether alexithymia can predict the improvement of pain severity following a treatment‐as‐usual programme for chronic musculoskeletal pain over and above psychological cofactors (emotional distress, catastrophizing, and self‐efficacy). A consecutive sample of 129 patients with diagnosed chronic musculoskeletal pain referred to two tertiary care centres was recruited and treated for 16 weeks. Clinical pain, psychological distress, self‐efficacy, catastrophizing, and alexithymia were assessed with validated self‐report measures at the first medical visit (T0) and at 16‐week follow‐up (T1). Compared with non‐responder patients (n = 72, 55.8%), those who responded (i.e., reduction of >30% in pain severity; n = 57, 44.2%) reported an overall improvement in psychological variables except alexithymia. Alexithymia showed relative stability between baseline and follow‐up within the entire sample and remained a significant predictor of treatment outcome even when other predictive cofactors (i.e., pain interference, depressive symptoms, and catastrophizing) were considered simultaneously. Our results suggest that identifying patients with a co‐occurrence between alexithymia, depressive symptoms, catastrophizing, and the stressful experience of chronic pain can be clinically relevant in pain prevention and intervention programs. [ABSTRACT FROM AUTHOR]

The main goal of this research activity is 3D data analysis and interpretation to study the geometric shaping of architectural elements belonging to Cultural Heritage moving from Point Cloud Semantic Segmentation to 3D modeling. We are testing Evolutionary Computing (EC) to study these shapes merging critical human-driven interpretation and Genetic Algorithms (GAs) driven interpretation. GAs allow to automate identification of open or closed polycentric curves (e.g. ovals) and of analytic curves (e.g. ellipse) starting from reality based planar sections (irregular polylines) extracted from point clouds. GAs, based on natural selection, are tools for solving both constrained and unconstrained optimization problems not well suited for standard algorithms. Moving from theoretical knowledge and treaties study, the research topic is the shape analysis and restitution of hemispherical domes profile (‘pointed arches’ or polycentric arches), i.e. ‘pointed domes’, and of ovoidal/ellipsoidal domes (generic and revolution surfaces). Starting from rules (from centers to points along profiles), our aim is to test a process to generate polycentric (closed or open) and elliptic profiles nearest to reality-based sections (from point along reality-based profiles to centers layout). The Evolutionary Solver (Galapagos component, GH, Rhino) starts from the identification of a given number of points (GENE POOL, i.e. variables) along the irregular reference polyline to select the best solutions (SELECTION) towards the optimal solutions (continuous semi-ideal profile) that best fit the reference curve by minimizing or maximizing different comparison conditions between the two curves (FITNESS).DOI: https://doi.org/10.20365/disegnarecon.26.2021.19

The intriguing electronic properties of two-dimensional materials motivates experiments to resolve their rapid, microscopic interactions and dynamics across momentum space. Essential insight into the electronic momentum-space dynamics can be obtained directly via time- and angle-resolved photoemission spectroscopy (trARPES). We discuss the development of a high-repetition rate trARPES setup that employs a bright source of narrowband, extreme-UV harmonics around 22.3 eV, and its application to sensitive studies of materials dynamics. In the bulk transition-metal dichalcogenide MoSe2 momentum-space quasiparticle scattering is observed after resonant excitation at the K-point exciton line, resulting in the time-delayed buildup of electrons at the Σ-point conduction band minimum. We will discuss this and other aspects of the non-equilibrium electronic response accessible with the extreme-UV trARPES probe.

Using angle resolved photoemission spectroscopy, we report the first band dispersions and distinct features of the bulk Fermi surface (FS) in the paramagnetic metallic phase of the prototypical metal-insulator transition material V_{2}O_{3}. Along the c axis we observe both an electron pocket and a triangular holelike FS topology, showing that both V 3d a_{1g} and e_{g}^{π} states contribute to the FS. These results challenge the existing correlation-enhanced crystal field splitting theoretical explanation for the transition mechanism and pave the way for the solution of this mystery.

Using angle resolved photoemission spectroscopy, we report the first band dispersions and distinct features of the bulk Fermi surface (FS) in the paramagnetic metallic phase of the prototypical metal-insulator transition material V_{2}O_{3}. Along the c axis we observe both an electron pocket and a triangular holelike FS topology, showing that both V 3d a_{1g} and e_{g}^{π} states contribute to the FS. These results challenge the existing correlation-enhanced crystal field splitting theoretical explanation for the transition mechanism and pave the way for the solution of this mystery.

In the underdoped copper-oxides, high-temperature superconductivity condenses from a nonconventional metallic "pseudogap" phase that exhibits a variety of non-Fermi liquid properties. Recently, it has become clear that a charge density wave (CDW) phase exists within the pseudogap regime. This CDW coexists and competes with superconductivity (SC) below the transition temperature Tc, suggesting that these two orders are intimately related. Here we show that the condensation of the superfluid from this unconventional precursor is reflected in deviations from the predictions of BSC theory regarding the recombination rate of quasiparticles. We report a detailed investigation of the quasiparticle (QP) recombination lifetime, τqp, as a function of temperature and magnetic field in underdoped HgBa2CuO(4+δ) (Hg-1201) and YBa2Cu3O(6+x) (YBCO) single crystals by ultrafast time-resolved reflectivity. We find that τqp(T) exhibits a local maximum in a small temperature window near Tc that is prominent in underdoped samples with coexisting charge order and vanishes with application of a small magnetic field. We explain this unusual, non-BCS behavior by positing that Tc marks a transition from phase-fluctuating SC/CDW composite order above to a SC/CDW condensate below. Our results suggest that the superfluid in underdoped cuprates is a condensate of coherently-mixed particle-particle and particle-hole pairs.

Abstract The BaAl4 prototype crystal structure is the most populous of all structure types, and is the building block for a diverse set of sub-structures including the famous ThCr2Si2 family that hosts high-temperature superconductivity and numerous magnetic and strongly correlated electron systems. The MA4 family of materials (M = Sr, Ba, Eu; A = Al, Ga, In) themselves present an intriguing set of ground states including charge and spin orders, but have largely been considered as uninteresting metals. We predict the exemplary compound BaAl4 to harbor a three-dimensional Dirac spectrum with non-trivial topology and possible nodal lines crossing the Brillouin zone, wherein one pair of semi-Dirac points with linear dispersion along the k z direction and quadratic dispersion along the k x /k y direction resides on the rotational axis with C 4v point group symmetry. An extremely large, unsaturating positive magnetoresistance in BaAl4 despite an uncompensated band structure is revealed, and quantum oscillations and angle-resolved photoemission spectroscopy measurements confirm the predicted multiband semimetal structure with pockets of Dirac holes and a Van Hove singularity (VHS) remarkably consistent with the theoretical prediction. We thus present BaAl4 as a topological semimetal, casting its prototype status into a role as a building block for a vast array of topological materials.