Photoemission Spectra from Reduced Density Matrices: the Band Gap in Strongly Correlated Systems

We present a method for the calculation of photoemission spectra in terms of reduced density matrices. We start from the spectral representation of the one-body Green's function G, whose imaginary part is related to photoemission spectra, and we introduce a frequency-dependent effective energy that accounts for all the poles of G. Simple approximations to this effective energy give accurate spectra in model systems in the weak as well as strong correlation regime. In real systems reduced density matrices can be obtained from reduced density-matrix functional theory. Here we use this approach to calculate the photoemission spectrum of bulk NiO: our method yields a qualitatively correct picture both in the antiferromagnetic and paramagnetic phases, contrary to mean-field methods, in which the paramagnet is a metal

Benessere e qualità della vita. Uno studio sulla salute degli scienziati sociali italiani al tempo della pandemia

Gli impatti della pandemia da Covid19 sono stati molteplici: sanitari, sociali, economici, politici, sulla qualità della vita e sul benessere. In seguito a una ricostruzione teorica del pensiero sociologico attinente al tema della salute, richiamando autori come Parsons, Merton, Weber, Marx, Goffman, Twaddle e tanti altri, l'obiettivo di questo progetto è cercare di studiare lo stato di salute mentale, i cui problemi sono in costante aumento, degli scienziati sociali accademici italiani in difficoltà durante il periodo della pandemia, in quanto svolgono un ruolo rilevante all'interno della società, cercando poi di costruire un indice che identifichi il loro livello di malessere. L’impianto operativo della ricerca si basa sulla costruzione di un questionario strutturato, sottoposto all’attenzione degli intervistati in forma auto-compilata. Lo strumento indaga alcuni aspetti della salute degli accademici italiani, impegnati nelle aree disciplinari delle scienze sociali. Sono tre le aree indagate: la percezione del proprio stato di salute (SF-36), la presenza di uno stato depressivo (PHQ-9), l’effetto del Covid sulle condizioni di lavoro (HSE). Nel complesso il lavoro indaga un fenomeno dalla forte rilevanza sociale e molto attuale; i risultati dell’analisi condotta, prima utilizzando l'analisi fattoriale esplorativa e poi la regressione logistica e l’approfondimento semantico offerto dall’analisi delle domande a risposta aperta, fanno luce su un fenomeno complesso, come quello della salute mentale degli scienziati sociali italiani, e sui molti fattori che minano la qualità del loro lavoro.The impacts of the Covid19 pandemic have been manifold: health, social, economic, political, on quality of life and well-being. Following a theoretical reconstruction of sociological thought relating to the theme of health, recalling authors such as Parsons, Merton, Weber, Marx, Goffman, Twaddle and many others, the aim of this project is to attempt to study the state of mental health, the problems of which are constantly increasing, of the Italian academic social scientists who were in difficulty during the period of the pandemic, as they played a relevant role within society, and then to attempt to construct an index identifying their level of malaise. The operational set-up of the research is based on the construction of a structured questionnaire, submitted to the respondents in a self-completed form. The instrument investigates certain aspects of the health of Italian academics, engaged in the disciplinary areas of the social sciences. Three areas are investigated: the perception of one's own state of health (SF-36), the presence of a depressive state (PHQ-9), the effect of Covid on working conditions (HSE). On the whole, the work investigates a phenomenon of strong social relevance and very topical; the results of the analysis conducted, first using exploratory factor analysis and then logistic regression and the semantic deepening offered by the analysis of open-ended questions, shed light on a complex phenomenon, such as the mental health of Italian social scientists, and on the many factors that undermine the quality of their work

Crystal structure of the ternary complex of Leishmania major pteridine reductase 1 with the cofactor NADP+/NADPH and the substrate folic acid

Pteridine reductase 1 (PTR1) is a key enzyme of the folate pathway in protozoan parasites of the genera Leishmania and Trypanosoma and is a valuable drug target for tropical diseases. This enzyme is able to catalyze the NADPH-dependent reduction of both conjugated (folate) and unconjugated (biopterin) pterins to their tetrahydro forms, starting from oxidized- or dihydrostate substrates. The currently available X-ray structures of Leishmania major PTR1 (LmPTR1) show the enzyme in its unbound, unconjugated substrate-bound (with biopterin derivatives) and inhibitor-bound forms. However, no structure has yet been determined of LmPTR1 bound to a conjugated substrate. Here, the high-resolution crystal structure of LmPTR1 in complex with folic acid is presented and the intermolecular forces that drive the binding of the substrate in the catalytic pocket are described. By expanding the collection of LmPTR1 structures in complex with process intermediates, additional insights into the active-site rearrangements that occur during the catalytic process are provided. In contrast to previous structures with biopterin derivatives, a small but significant difference in the orientation of Asp181 and Tyr194 of the catalytic triad is found. This feature is shared by PTR1 from T. brucei (TbPTR1) in complex with the same substrate molecule and may be informative in deciphering the importance of such residues at the beginning of the catalytic process

Educational robotics studies in Italian scientific journals: A systematic review

In recent years, there has been increasing attention to applying educational robotics (ER) in learning settings and, consequently, it has concerned and involved the entire pedagogical field, giving rise to a large amount of experimentation and research. Educational robots are used within the school curriculum and in extra-curricular activities to improve student interest, engagement and academic achievement in various fields, such as STEM and digital literacy, and in many other ways, for example fostering specific cognitive and socio-relational skills. In Italy, as in many other countries, an increasing number of publications are featuring this subject. While there are also some reviews, none of them has been interested in reviewing studies published in Italian journals. The aim of this work is to provide a systematic review of the literature regarding studies investigating educational robotics and provide suggestions for further research and teaching practices. To do this we used the PRISMA statement process. In total, 28 studies published between 2011 and 2021 in 49 Italian journals were analyzed. The main findings from this review provide the current state of the art on research in ER. Furthermore, the paper discusses trends and the vision toward the future and opportunities for further research

Damped Lyman-α\alpha absorbers and atomic hydrogen in galaxies: the view of the GAEA model

Using the GAEA semi-analytic model, we analyse the connection between Damped Lyman-$\alpha$ systems (DLAs) and HI in galaxies. Our state-of-the-art semi-analytic model is tuned to reproduce the local galaxy HI mass function, and that also reproduces other important galaxy properties, including the galaxy mass - gas metallicity relation. To produce catalogs of simulated DLAs we throw $10^5$ random lines of sight in a composite simulated volume: dark matter haloes with log$(\frac{M_{200}}{ M_{\odot}}) \geq 11.5$ are extracted from the Millennium Simulation, while for $9.2 \leq \log(\frac{M_{200}}{ M_{\odot}})<11.5$ we use the Millennium II, and for $8 \leq \log(\frac{M_{200}}{M_{\odot}}) < 9.2$ a halo occupation distribution model. At $2 < z < 3$, where observational data are more accurate, our fiducial model predicts the correct shape of the column density distribution function, but its normalization falls short of the observations, with the discrepancy increasing at higher redshift. The agreement with observations is significantly improved increasing both the HI masses and the disk radii of model galaxies by a factor 2, as implemented 'a posteriori' in our $2M-2R$ model. In the redshift range of interest, haloes with $M_{200} \geq {10}^{11} M_{\odot}$ give the major contribution to $\Omega_{\rm DLA}$, and the typical DLA host halo mass is $\sim {10}^{11} M _{\odot}$. The simulated DLA metallicity distribution is in relatively good agreement with observations, but our model predicts an excess of DLAs at low metallicities. Our results suggest possible improvements for the adopted modelling of the filtering mass and metal ejection in low-mass haloes.Comment: 21 pages, 16 figures. Accepted for publication in MNRA

Recent Progress in Photoresponsive Biomaterials

: Photoresponsive biomaterials have garnered increasing attention recently due to their ability to dynamically regulate biological interactions and cellular behaviors in response to light. This review provides an overview of recent advances in the design, synthesis, and applications of photoresponsive biomaterials, including photochromic molecules, photocleavable linkers, and photoreactive polymers. We highlight the various approaches used to control the photoresponsive behavior of these materials, including modulation of light intensity, wavelength, and duration. Additionally, we discuss the applications of photoresponsive biomaterials in various fields, including drug delivery, tissue engineering, biosensing, and optical storage. A selection of significant cutting-edge articles collected in recent years has been discussed based on the structural pattern and light-responsive performance, focusing mainly on the photoactivity of azobenzene, hydrazone, diarylethenes, and spiropyrans, and the design of smart materials as the most targeted and desirable application. Overall, this review highlights the potential of photoresponsive biomaterials to enable spatiotemporal control of biological processes and opens up exciting opportunities for developing advanced biomaterials with enhanced functionality

Modular design towards the circular economy – From ‘making to unmake’ to ‘making to remake'

Given the recent debate regarding the transition to the Circular Economy, Design for Modularity strategies play a decisive role in the process of transforming the current economic model from linear to circular. By describing some recently developed modular product case studies, this article intends to outline the considerations developed in the field of design culture for sustainability, on the concept of modularity. In recent years, this has shifted from the industrial logic of ‘making to unmake’, namely designing modular and disassemblable products mainly to recycle their end-of-life materials, to the logic of ‘making to remake’, to increase their circularity and durability, thereby making them reusable, repairable and remanufacturable. The objective of this contribution is to re-examine the concept of ‘modularity’ in the Circular Economy scenario, as a strategic design lever to extend the useful life of industrial products.   Article info Received: 12/09/2023; Revised: 16/10/2023; Accepted: 22/10/202

The Quantum Frontier of Software Engineering: A Systematic Mapping Study

Context. Quantum computing is becoming a reality, and quantum software engineering (QSE) is emerging as a new discipline to enable developers to design and develop quantum programs. Objective. This paper presents a systematic mapping study of the current state of QSE research, aiming to identify the most investigated topics, the types and number of studies, the main reported results, and the most studied quantum computing tools/frameworks. Additionally, the study aims to explore the research community's interest in QSE, how it has evolved, and any prior contributions to the discipline before its formal introduction through the Talavera Manifesto. Method. We searched for relevant articles in several databases and applied inclusion and exclusion criteria to select the most relevant studies. After evaluating the quality of the selected resources, we extracted relevant data from the primary studies and analyzed them. Results. We found that QSE research has primarily focused on software testing, with little attention given to other topics, such as software engineering management. The most commonly studied technology for techniques and tools is Qiskit, although, in most studies, either multiple or none specific technologies were employed. The researchers most interested in QSE are interconnected through direct collaborations, and several strong collaboration clusters have been identified. Most articles in QSE have been published in non-thematic venues, with a preference for conferences. Conclusions. The study's implications are providing a centralized source of information for researchers and practitioners in the field, facilitating knowledge transfer, and contributing to the advancement and growth of QSE