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A simplified system for the detection of antennal responses to host-borne volatile organic compounds in sand flies
No full textBackground: Phlebotomus (Larroussius) perniciosus (Diptera: Psychodidae) is the most common and predominant vector of Leishmania infantum in the Western Mediterranean region. Volatile organic compounds (VOCs) produced by vertebrates are important cues affecting the behaviour of blood-feeding insects. Generally, the identification of putative behaviourally active VOCs involves three distinct phases: extraction, chemical characterization and chemoreceptivity evaluation using electrophysiological techniques. Here, we present a simplified gas chromatography-mass spectrometry-electroantennographic detection (GC-MS-EAD) setup adapted for screening bioactive compounds in sand flies, in which the chemical identification and antennal responses are recorded simultaneously. Methods: The method integrates: (i) a flow-splitter that balances the flow rate of the two outgoing streams, (ii) GC columns with different lengths and diameters in the two sections splitter-MS and splitter-EAD and (iii) an antennal signal amplifier. The GC-MS-EAD analysis was applied to headspace solid-phase microextraction (HS-SPME) extracts from a healthy dog, and antennal responses were recorded in female P. perniciosus sand flies. Results: The canine VOC profile was predominantly composed of aldehydes, with hexanal and nonanal eliciting the strongest antennal responses in P. perniciosus. Conclusions: This simplified GC-MS-EAD system shows promise for broader application in the study of host-vector interactions. Its use across different host-vector pairs may enhance our understanding of these relationships and inform the development of strategies for integrated vector monitoring and control
Environmental Assessment of a Heritage Forest Urban Park on the Densely Populated Coast of Versilia, Italy
No full textThe present study focuses on the sources and spatial distribution of potentially toxic elements (PTEs) and organic pollutants in water, canal bed sediment, and soil in the Versiliana urban park, an inclusive green area near the coast in the densely populated Versilia Plain of Tuscany. Surface water and bed sediments from canals crossing the urban park were collected at 10 stations during four different surveys to account for hydrological seasonality. Groundwater was collected in a survey through 10 piezometers. Eleven shallow soil samples were also collected, with the aim of evaluating the potential release of pollutants. Groundwater ranged from Ca-HCO3, to NaCl, CaCl2, and Na-HCO3 water types, indicating conservative mixing and cation exchange processes during seawater intrusion. Most waters from canals belonged to the Ca-HCO3 hydrofacies; a salinization shift, due to hydraulic connection with saline groundwater and soil sea salt dissolution, is observed. The concentration of most PTEs in groundwater and canal water is below Italian regulatory thresholds, with the only exception being As, which exceeds the legal limit in some samples. In most sediments, Ni, Cr, Zn, and As exceed the threshold effect concentration, and in some cases, the probable effect concentration. Geogenic PTE sources are attributed to metalliferous mineralization that characterizes the upstream Versilia River basin catchment. However, local PTE inputs from vehicular emissions and local industrial activities have been highlighted. Arsenic in sediments originated from geogenic sources and from arsenical pesticides, as indicated by the analysis of organic compounds, highlighting the legacy of the use of organic pesticides that have settled in bed sediments, in particular malathion and metalaxyl. The arsenic risk-based screening level in soil is lower compared with the regulatory threshold and with the measured concentration
Limiti all'ammissibilità del referendum abrogativo: ambiti di esplicazione e identità di un istituto in crisi
No full textIl lavoro tratta i limiti all'ammissibilità del referendum abrogativo, evidenziando profili problematici del controllo sull'ammissibilità e dello stesso referendum, che si ripercuotono tanto sui cc.dd. limiti impliciti quanto sui cc.dd. limiti espliciti. Si presentano anche alcune proposte di intervento sui limiti e sul relativo controllo
Generalized energy conservation for linear wave equations with time-dependent propagation speed
No full textWe consider a wave equation with a time-dependent propagation speed, whose potential oscillations are controlled through bounds on its first and second derivatives and by limiting the integral of the difference with a fixed constant. We investigate when the wave equation exhibits generalized energy conservation (GEC), meaning that the energy of all solutions remains bounded for all times by a multiple of the initial energy. When GEC is not satisfied, we provide upper bounds for the growth of the energy. These upper bounds are derived by analyzing the growth of the Fourier components of the solution. Depending on the frequency and the time interval, different energy inequalities are employed to fully exploit our assumptions on the propagation speed. Finally, we present counterexamples that demonstrate the optimality of our upper bound estimate
Lo sviluppo del mentoring nel contesto italiano: formazione e ricerca nell’Università di Pisa
No full textIl contributo presenta un progetto di mentoring come importante risorsa per la qualificazione professionale della docenza universitaria. Nello specifico, si approfondisce l’esperienza di mentoring tra pari proposta presso l’Università di Pisa nel 2022, denominata “Progetto Comunità di Mentori” (PCM)
La disuguaglianza climatica: una nuova dimensione della crisi urbana.
No full textNell’attuale contesto urbano, le crisi delle città sono sempre più legate alle sfide imposte dal cambiamento climatico, che amplifica criticità sociali,
economiche e spaziali. Il presente studio analizza l’interconnessione tra giustizia sociale e sostenibilità ambientale, focalizzandosi sulle disuguaglianze
climatiche a livello regionale in Italia. Attraverso un approccio multidisciplinare e dati quantitativi relativi ad indicatori socioeconomici e di sostenibilità
ambientale, la ricerca evidenzia significative differenze tra le regioni del Nord e del Sud Italia. I risultati indicano la necessità di sviluppare politiche
urbane inclusive e sostenibili che promuovano la giustizia climatica e riducano le disuguaglianze socioeconomiche, regolamentando adeguatamente le
partnership pubblico-private per garantire equità e trasparenza nella gestione delle risorse naturali e dei servizi pubblici.In the current urban context, city crises are increasingly linked to the challenges posed by climate change, which amplifies social, economic, and spatial
issues. This study analyses the interconnection between social justice and environmental sustainability, focusing on climate inequalities at the regional
level in Italy. Through a multidisciplinary approach and quantitative data on socio-economic and environmental sustainability indicators, the research
highlights significant differences between the northern and southern regions of Italy. The results indicate the need to develop inclusive and sustainable
urban policies that promote climate justice and reduce socio-economic inequalities, adequately regulating public-private partnerships to ensure equity
and transparency in the management of natural resources and public services
Virtual Reality Laboratory for Engineering and Material Science Immersive Learning
No full textThe 2030 Agenda for Sustainable Development, adopted by the United Nations, underscores the importance of inclusive and equitable quality education to promote global awareness. However, progress in this field has been delayed by global crises, including the COVID-19 pandemic and conflicts, highlighting the urgent need for innovative educational solutions. Virtual reality (VR) offers significant potential for creating personalized and inclusive learning environments, particularly in science, technology, engineering, and mathematics (STEM) education. This study presents the development and evaluation of an immersive virtual reality laboratory (VR Lab) focused on material science and mechanics. The VR Lab aims to enhance students' comprehension of complex micro and macro engineering phenomena and strengthen their cognitive skills. Employing a usability and effectiveness evaluation among undergraduate engineering students, the study provides preliminary evidence of VR's efficacy as an educational tool. Results demonstrate notable improvements in students' ability to visualize complex concepts and apply theoretical knowledge to practical scenarios, bridging the gap between theory and practice. The immersive nature of VR not only enhances engagement but also promotes a deeper understanding of key engineering and material science topics. These findings support the integration of VR in STEM education as a complementary tool for enriching learning experiences and promoting educational inclusivity
Enhancing Torrefaction Process Modeling with Data Augmentation: a Study on Agri-Food Residues
No full textAgri-Food residues can pose environmental challenges, but through proper valorization, they can support
circular economy principles by providing alternatives to fossil fuels. This study focuses on modeling the
torrefaction process of an industrial hazelnut processing waste (i.e., roasted cuticles) to produce high-density
solid biofuels. An Artificial Neural Network (ANN) model is proposed. The work leverages the innovative
approach of data augmentation through Gaussian noise addition to a relatively scarce experimental dataset.
The expanded dataset greatly improved the Neural Network prediction performance: the method achieved
considerably lower mean square error compared to the model output based on experimental data only. This
approach offers several benefits: it enables accurate modeling with limited experimental data, reduces the need
for extensive experimental work, lowers costs, and improves process optimization capabilities, presently in
torrefaction processing and, more in general, in resource utilization and waste management
An Upper-Limb Prosthetic Approach to Reduce Compensatory Motions in Reaching Tasks
No full textIn contemporary studies within the upper-limb prosthetic field, current investigations persistently revolve around the research of innovative control methodologies. These works are driven by the intention to diminish cognitive fatigue experienced by users while simultaneously enhancing the resilience and intuitiveness of control mechanisms. Several investigations have introduced approaches involving the exploitation of corrective movements as indicators of control system error, effectively closing the control loop. In prior studies, a predetermined linkage associates specific compensatory motions with distinct degrees of freedom in prosthetic devices. In contrast to this precedent, our study introduces a methodology that circumvents this intermediary step, enabling a direct mapping between human motions and the number of prosthetic joints. The proposed algorithm has been instantiated and validated using Matlab/Simulink, employing a simulated scenario featuring a trans-humeral prosthetic user