Archivio Istituzionale della Ricerca- Università del Salento
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Propionic acid toxicity and utilization of α-ketobutyric acid in Neisseria meningitidis via the methylcitrate cycle under specific conditions
No full textNeisseria meningitidis is a human-specific, transient colonizer of the nasopharynx that occasionally causes invasive disease. It can utilize a limited range of compounds as primary carbon sources, including glucose, maltose, lactate, and pyruvate, which are present in varying concentrations in microenvironments relevant to meningococcal infection. Additionally, intermediates from the tricarboxylic acid cycle, such as succinate, fumarate, and malate, as well as amino acids like glutamate, are utilized as supplementary carbon sources. Notably, N. meningitidis also possesses a functional methylcitrate cycle (MCC), which enables the assimilation of propionic acid and mitigates its toxicity. In this study, we investigated propionate toxicity and MCC functionality in wild-type N. meningitidis strains and prpB-, prpC-, ackA1-, and ackA2-defective mutants under various growth conditions. We observed that propionate toxicity was influenced by the primary carbon source and additional factors, such as bicarbonate. Specifically, prpB- and prpC-defective mutants showed high sensitivity to propionate when cultured with glucose or pyruvate, but were not inhibited even by high concentrations of propionate when grown with lactate. The mechanisms underlying the conditional toxicity of propionate were further explored and discussed. Additionally, in the genome of 41 out of 128 N. meningitidis strains, we identified a gene encoding a transporter from the 4-toluene sulfonate uptake permease family, located between prpC and acnD in the MCC gene cluster. Genetic inactivation of this gene, named kbuT, impaired the ability to take up and oxidize alpha-ketobutyrate, an alpha-keto acid abundant in host cells, which can be used as a carbon source through the MCC.IMPORTANCEMeningococci are metabolically versatile organisms, switching between intracellular and extracellular lifestyle during colonization and invasive disease. Niche switching impacts on how bacteria communicate with host to find a balance between nutrient assimilation and protection against toxicity of some metabolites. The methylcitrate pathway fulfills this function, providing a compromise between propionate assimilation and propionate detoxification, in relation to the colonized host microenvironments. In this study, we revealed an unexpected difference in the sensitivity of meningococci to propionate when grown with different carbon sources. We also characterized the function of a gene located within the prp operon that encodes a transporter of alpha-ketobutyrate, an alpha-ketoacid abundant in host cells. These results contribute to extending our understanding of the metabolic adaptation mechanisms, which are crucial for meningococcal infection and virulence within the host microenvironments
Assessing Policy Impact on Smart Farming Technology Adoption Under Ambiguity and Network Influence
No full textWe introduce a novel approach that integrates variational analysis, fuzzy uncertainty, and multi-criteria methods to analyse the adoption of smart farming practices in environments marked by spatial diversity and uncertain comprehension of the primary factors influencing adoption. Our approach considers both local factors specific to rural areas and external factors, such as the influence of non-local information sources, including innovative platforms and trans-regional networks. This methodology can be employed to assess the effectiveness of policies aimed at enhancing the acquisition of smart innovations in the agricultural sector
Collaborative Learning in Schools: An Experimental Approach to the Development of Teaching-Learning Processes
No full textEnhanced Range Dual-Coil NFC Antenna System for Diverse Near Field Applications
No full textIn near field communication (NFC), the operational range is typically constrained by the antenna dimensions and coil design. This paper introduces an innovative dual-coil NFC antenna system designed to increase this range to ensure more robust communication over increased distances and for wearable sensors applications. For the purpose, two in-phase circular coils are positioned on opposite sides of the same substrate, connected in series through appropriate via hole. This arrangement effectively increases both the coil length and turn count saving the substrate footprint. The outer diameter of each coil is 30mm and they are connected in series by a via hole in a 0.05mm thick commercial flexible substrate polyimide. The use of thin flexible substrate is aimed to ensure the availability of profile NFC antenna structure for various near field applications (cellular NFC-based communications and wearable real-time monitoring system of critical physiological parameters). Comprehensive design optimization has been conducted using ANSYS Electronics Desktop, accompanied by mutual positional (sliding and vertical) analyses to compare the field ranges achievable with dual-coil versus single-coil configurations
The Influence of Ecological Materials on Consumer Purchase Behavior: An Analysis of the Sustainable Fashion Sector
No full textL’Istantaneità nei Processi di Consumo: La Compressione del Processo d’acquisto nell’epoca del Marketing Ipnotico
No full textEconomia e società nel pensiero di Salvatore Morelli
No full textSalvatore Morelli (1824-1880) emerge come una figura di spicco nel panorama intellettuale e politico italiano del XIX secolo, celebre soprattutto per la sua pionieristica difesa dei diritti delle donne. La sua opera principale, La Donna e la Scienza (I ed. 1861), si configura come un testo fondamentale che anticipa e affianca le riflessioni di pensatori sul tema dell’emancipazione femminile, come John Stuart Mill con il suo The Subjection of Women (1869). Dalla formazione di Morelli non emerge un interesse specifico per le questioni economiche, né nei suoi scritti può essere rintracciato un filone coerente di analisi delle questioni economiche del tempo. Questo contributo si propone di esplorare la dimensione economica del pensiero di Morelli, argomentando come le sue idee sul ruolo e sui diritti delle donne avessero implicazioni economiche significative nel contesto storico del suo tempo
Raoul Schrott. Viaggio all'origine della poesia
No full textThis study is dedicated to the complete poetic works of contemporary Austrian poet Raoul Schrott, offering for the first time an overview through an interpretative analysis of his texts and themes. It ranges from his debut in the late 1980s, marked by his encounter with the creative brilliance of H.C. Artmann, to the search for his own poetics, which is already evident in the collection Hotels (1995), and continues through subsequent anthologies to the recent Inventur des Sommers (2023), in which the poet travels once again to the land of the ancient Muses. Schrott's poetry touches on themes such as the sublime, the perception of nature, atheism, time, love and absence. It is influenced by the charm of beginnings and, in its development, encompasses the metapoetic question of its own origin, the architecture and functions of poetic composition as a literary genre par excellence, even in today's world. His is a universal poetry, echoing the literary knowledge of a multilingual world by tradition; a lyrical narration of the humana conditio focused on establishing the forms of its authenticity.
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Questo studio è dedicato all’opera in versi del poeta austriaco contemporaneo Raoul Schrott, di cui si cerca per la prima volta di offrire una visione d’insieme attraverso un percorso interpretativo dei testi e dei temi. Si va dagli esordi sul finire degli anni Ottanta, segnati dall’incontro con l’estro creativo di H.C. Artmann, alla ricerca di una propria poetica, che si delinea già nella raccolta Hotels (1995); si giunge, attraverso le sillogi successive, alla recente Inventur des Sommers [Inventario dell’estate, 2023], in cui il poeta torna a viaggiare nella terra delle antiche Muse. La poesia di Schrott tocca temi quali il sublime, la percezione della natura, l’ateismo, il tempo, l’amore, l’assenza; essa risente del fascino degli inizi e racchiude, nel suo sviluppo, l’interrogativo metapoetico sulla propria origine, sull’architettura e le funzioni del componimento poetico come genere d’elezione, anche nel mondo di oggi. È una poesia universale, in cui riecheggia il sapere letterario di un mondo tradizionalmente plurilingue; una narrazione lirica della humana conditio concentrata a stabilire le forme della sua autenticità
Le "lotte per la terra" e i "decreti Gullo". Appunti politico-istituzionali di un conflitto sociale (1943-1951)
No full textIl contributo si occupa di indagare la nascita e gli sviluppi sociali e politici del movimento italiano delle "lotte per la terra" come possibile caso studio della prassi politica di gestione dei conflitti sociali mediante la loro istituzionalizzazione. Il movimento visse la sua stagione più intensa nel Secondo dopoguerra, quando la classe contadina diede vita ad una mobilitazione collettiva che coinvolse tutto il Mezzogiorno e che trovò il suo epilogo istituzionale nell'adozione dei "decreti Gullo" (1944-1946). I decreti diedero avvio ad un processo politico e culturale che confluì nella progressiva conversione del modello di proprietà agricola feudale in proprietà agricola sociale
Measurement of top-quark pair production in association with charm quarks in proton–proton collisions at sqrt(s) = 13 TeV with the ATLAS detector
Get PDFInclusive cross-sections for top-quark pair production in association with charm quarks (c) are measured with proton–proton collision data at a center-of-mass energy of 13 TeV corresponding to an integrated luminosity of 140 fb-1, collected with the ATLAS experiment at the LHC between 2015 and 2018. The measurements are performed by requiring one or two charged leptons (electrons and muons), two b-tagged jets, and at least one additional jet in the final state. A custom flavor-tagging algorithm is employed for the simultaneous identification of b-jets and c-jets. In a fiducial phase space that replicates the acceptance of the ATLAS detector, the cross-sections for ttˉ +1c-jet production are measured to be 1.28+0.27-0.24 pb and 6.4+1.0-0.9 pb, respectively. The measurements are primarily limited by uncertainties in the modeling of inclusive ttbar and ttbar + bbbar production, in the calibration of the flavor-tagging algorithm, and by data statistics. Cross-section predictions from various ttbar simulations are largely consistent with the measured cross-section values, though all underpredict the observed values by 0.5 to 2.0 standard deviations. In a phase-space volume without requirements on the ttbar + >= 2c and ttbar + 1c to total ttbar + jets production are determined to be (1.23+.0.25)% (8.8+-1.3)