The interaction-strength interpolation method for main-group chemistry: benchmarking, limitations, and perspectives

We have tested the original interaction-strength-interpolation (ISI) exchange-correlation functional for main group chemistry. The ISI functional is based on an interpolation between the weak and strong coupling limits and includes exact-exchange as well as the G\"orling-Levy second-order energy. We have analyzed in detail the basis-set dependence of the ISI functional, its dependence on the ground-state orbitals, and the influence of the size-consistency problem. We show and explain some of the expected limitations of the ISI functional (i.e. for atomization energies), but also unexpected results, such as the good performance for the interaction energy of dispersion-bonded complexes when the ISI correlation is used as a correction to Hartree-Fock.Comment: 20 pages, 20 figure

Semiclassical atom theory applied to solid-state physics

Using the semiclassical neutral atom theory, we extend to fourth order the modified gradient expansion of the exchange energy of density functional theory. This expansion can be applied both to large atoms and solid-state problems. Moreover, we show that it can be employed to construct a simple and non-empirical generalized gradient approximation (GGA) exchange-correlation functional competitive with state-of-the-art GGAs for solids, but also reasonably accurate for large atoms and ordinary chemistry.Comment: 10 pages, 7 figure

ChatGPT as Co-Advisor in Scientific Initiation: Action Research with Project-Based Learning in Elementary Education

Background: In the contemporary educational landscape, technology has the power to drive innovative pedagogical practices. Overcoming the resistance of teachers and students to adopting new methods and technologies is a challenge that needs to be addressed. Objectives: To evaluate the effectiveness of ChatGPT as a co-advisor in research projects and its influence on the implementation of Project-Based Learning (PBL), as well as overcoming resistance to the use of new pedagogical methodologies. Design: An action-research methodology was employed, including unstructured interviews and the application of questionnaires via Google Forms. Setting and Participants: The research was conducted in an elementary school, involving 353 students and 16 teachers. Data Collection and Analysis: Data were gathered through observations and notes in meetings and interviews, complemented by electronic questionnaires, with quantitative and qualitative analyses performed via Microsoft Excel and Google Forms. Results: The introduction of ChatGPT as a pedagogical tool led to increased student engagement and decreased teacher resistance, reflected in recognition at local science fairs. Conclusion: The study confirmed the utility of ChatGPT in school research co-orientation, highlighting its role in facilitating PBL and promoting cultural changes in educational practice, with proactive school management identified as a catalysing element in adapting to educational innovations

Il Casentino: tradizioni etnofarmacobotaniche nei comuni di Poppi e Bibbiena (Arezzo - Toscana)

The Casentino area: ethnopharmacobotanical traditions in the towns of Poppi and Bibbiena (Arezzo-Tuscany). The results refer an ethnopharmacobotanical study carried out in the territories of Poppi and Bibbiena in the Casentino area. There are 89 plants used in folk medicine; some of them are not known to scientific medicine (Asplenium trichomanes L., Fagus sylvatica L., Malva sylvestris L., Nerium oleander L. and Tamus communis L.)

Composición de la materia orgánica particulada en un sistema periantártico semi-cerrado: el Estrecho de Magallanes

The elemental and biochemical composition of particulate organic matter (POM) was investigated in the Straits of Magellan during February-March 1991. Twenty-two stations were selected in order to identify different areas of the Magellan ecosystem from a trophic point of view. The Strait of Magellan can be divided into three subsystems characterized by different hydrological and geomorphological conditions. Seston concentrations were mostly constrained by physical events, particularly the influence of oceanic and land run-off water inputs and the strong vertical mixing and resuspension events. POM composition displayed quali-quantitative differences between the three areas. In the first subsystem, influenced by Pacific waters, the low seston and POM concentrations and the high POC/Chl-a ratio values indicated the general predominance of the detrital and heterotrophic fractions. In the second subsystem, characterized by superficial stratification, higher seston and organic matter concentrations and lower values of POC/Chl-a ratio were found, indicating that this subsystem was influenced by an active autotrophic component. Shallow waters with intense tidal regime and strong vertical mixing characterized the third subsystem, connected to the Atlantic Ocean, which displayed an increasing importance of the inorganic fraction (values of the POC/TSM ratio lower than in the other systems). Moreover, the third subsystem showed higher values of the RNA/DNA ratio, possibly indicating that resuspension events may enhance the metabolic state of the organic particles mainly dominated by heterotrophic components.Se estudió la composición elemental y bioquímica de la POM (materia orgánica particulada) en el Estrecho de Magallanes durante el periodo febrero-marzo de 1991. Se eligieron 22 estaciones a fin de identificar diferentes áreas del ecosistema magallánico desde un punto de vista trófico. De acuerdo con las características hidrológicas y geomorfológicas dicho Estrecho se puede dividir en 3 subsistemas. Las concentraciones de seston estuvieron condicionadas, principalmente, por los fenómenos físicos y, en particular, por los aportes oceánicos y terrestres, por la mezcla vertical y por los fenómenos de resuspensión. La composición de la materia orgánica particulada (POM) mostró diferencias cualitativas y cuantitativas en las tres áreas. En el primer subsistema, influenciado por las aguas del Océano Pacífico, las bajas concentraciones de seston y POM y los altos valores de la relación POC/clorofila a indicaron una predominancia general de las fracciones detrítica y heterótrofa. En el segundo subsistema, caracterizado por una estratificación superficial, se encontraron altas concentraciones de seston y de materia orgánica y bajos valores de la relación POC/clorofila a, señalando una influencia de la componente autótrofa activa. El tercer subsistema, conectado con el Océano Atlántico y caracterizado por aguas poco profundas y por un régimen mareal intenso y una fuerte mezcla vertical, mostró un importante aumento de la fracción inorgánica (valores de la relación POC/TSM más bajos que en los otros dos subsistemas). Por otra parte, el tercer subsistema mostró altos valores de la relación RNA/DNA, indicando que posiblemente el estado metabólico de las partículas orgánicas (dominadas principalmente por componentes heterótrofas) estaría influenciado por fenómenos de resuspensión

Safety Concerns and Chemical Aspects of Improvised Explosive Devices and Homemade Explosives

The continuous changes in socio-political scenarios of the last decades led to an impressive increase in terrorist events related to the use of improvised explosive devices (IEDs). The energetic material contained in them, representing the essential part of the apparatus, is object of intense investigation owing to the need of optimizing many variables, namely the chemical energy storage of the detonating compound, the availability of raw materials required for its synthesis, the ease of process synthesis by commonly used tools and the stability of the chemical energy carrier towards transport and handling. This critical analysis proposes a classification of the detonating compounds or mixtures according to their chemical, thermodynamic and ballistic properties that make them basic ingredients in IEDs and homemade explosives. The wide and always growing variety of ingredient combination poses a challenging problem of chemical identification, owing to an interference of signals in analytical data regression. Finally, a discussion on technical realizations of such improvised weapons is outlined in light of the recent protocols of process safety and disaster control

Identification of D179H, a novel missense GJB2 mutation in a Western Sicily family

The main purpose of this study was to describe a novel missense mutation (p.D179H) found in a Western Sicily family and to examine the genetic and audiologic profiles of all family members by performing a GJB2 and GJB6 mutations analysis and a complete audiologic assessment. The proband was a 3-month-old infant with a congenital profound sensorineural hearing loss; direct sequencing of the GJB2 revealed the presence of a c.35delG mutation in the heterozygous state and a heterozygous G[C transition at nucleotide 535 in trans; this novel mutation, called p.D179H, resulted in an aspartic acid to histidine change at codon 179. It was also evidenced in the heterozygous state in two members of this family, both with normal hearing. No GJB6 mutations were evidenced in all subjects studied. Considering the genotypic and phenotypic analysis of all family members, we suggest, differently from the p.D179 N mutation previously reported, a recessive mode of inheritance. Functional studies on p.D179H have to be performed to confirm our hypothesis

Nano risk evaluation in laboratory environment by a customized layer of protection analysis approach

Nanotechnologies are widely used in various industrial settings and by the year 2020, it is expected that nearly 20 % of all products manufactured in the world will take a certain amount of nanotechnology. However, there is a substantial imbalance of knowledge between application of nanotechnology and its impact on health and environment, also considering that nanoparticle synthesis by chemical methods assumed a key role for economic, industrial and scale-up issues. The information currently available on nanomaterial risk assessment within the workplace are limited: systematic methods for assessing exposure are not known yet and the number of workers exposed is hardly estimated. This knowledge gap imposes to the scientific community the need to join efforts to provide a shared opinion on safety, health and welfare of workers who use, manipulate, or produce nanomaterials, adopting as well preventive and protective measures proportionated to the risk according to the precautionary principle. We develop a novel framework for Nano Risk Assessment within the laboratory context, by combining LOPA and HazId techniques, assigning credit factors to specific operative procedures and safety training, suitable to mitigate risk exposure and avoid over-conservative evaluations. Conclusions are drawn on applicative results and possible direction for further implementation of the approach, in view of sustainable, healthy and safe production at research and industrial level