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Maximal Elements of Preferences on Compact Spaces from Optimization of One-Way Utilities
Full text linkThe search for maximal elements of preference relations has been recently related to the optimization of one-way utilities on compact topological spaces. In this paper, we deepen this study by referring to upper semicontinuous finite Richter–Peleg multi-utility representations of preorders. We provide necessary and sufficient conditions for the existence of representations of this kind and then, under the assumption of near-completeness, we characterize the identification of all maximal elements by maximizing all functions in an appropriate representation under compactness
Inteligência Artificial em Ciência Animal: Aplicações em Pesquisa e na Indústria
No full textO livro Inteligência Artificial em Ciência Animal: Aplicações em Pesquisa e na Indústria (ISBN: 978-65-5790-123-6) apresenta uma análise aprofundada e aplicada do uso de Inteligência Artificial na produção animal, na saúde e no bem-estar, bem como na cadeia de alimentos de origem animal.
A obra contextualiza a evolução da IA, abrangendo desde princípios fundamentais até técnicas atuais, como aprendizado profundo, visão computacional, algoritmos genéticos e processamento de linguagem natural. Na sequência, discute os fundamentos da Ciência Animal — comportamento, saúde, genética, nutrição, produção e qualidade de alimentos — estabelecendo as bases para a integração entre métodos computacionais e desafios biológicos.
Tópicos desenvolvidos incluem qualidade e pré-processamento de dados, aprendizado supervisionado e não supervisionado, métricas de desempenho, otimização e formulação de funções objetivo. Entre os exemplos práticos estão: detecção de mastite, classificação da qualidade da carne, análise de comportamento e identificação de anomalias em produtos como leite, carnes, ovos e mel.
A obra dedica um capítulo extenso a sensores artificiais e Internet das Coisas, abordando seu papel no monitoramento fisiológico, ambiental e produtivo. Também explora aplicações de visão computacional em inspeção industrial, diagnóstico veterinário, análise espectral e monitoramento comportamental. O livro discute ainda temas éticos e regulatórios, como viés algorítmico, transparência, explicabilidade e responsabilidade no uso de IA.
A conclusão apresenta perspectivas futuras para o uso de IA na Ciência Animal, destacando sensores avançados, gêmeos digitais e sistemas automatizados orientados pela sustentabilidade e pelo bem-estar animal
Sustainable multi-objective optimization problem for environmental impact and electricity production analysis of dams
No full textIn this paper, we develop a multi-objective optimization framework that employs a variant of the Multi-Objective Particle Swarm Optimizer (MOPSO) to balance the competing objectives represented by the total electricity generation and the reduction of carbon emissions, due to the construction of dams. This challenge highlights two conflicting aspects in the context of climate change and sustainability: on the one hand, hydropower represents a renewable energy source; on the other hand, the construction of dams leads to large greenhouse gas emissions. We analyse a dataset of 509 dams in the Amazon basin, categorized by geographical and technical features, to assess the impact of site selection. We further inspect the key features of dams that compose the best configurations to maximize energy output while minimizing emissions. The results show that, in such configurations, the most efficient dams are located in the upland zones of Peru, while inefficient dams are located on Brazilian territory, whose geographic conformation allows the construction of only downland dams that have a greater environmental impact due to a larger reservoir to satisfy a determined energy need. Finally, it seems that some existing dams are completely inefficient from the optimization viewpoint
Therapeutic potential of butyrate supplementation in sepsis: a review of preclinical evidence and translational perspectives
Full text linkSepsis remains a major global health problem and is responsible for millions of deaths annually despite significant progress in antimicrobial therapy and organ support. Increasing evidence highlights the role of the gut–immune axis in shaping host responses during sepsis, with particular interest in microbiota-derived metabolites such as short-chain fatty acids (SCFAs). Among these, butyrate has emerged as a promising candidate due to its anti-inflammatory, immunomodulatory, and intestinal barrier–preserving properties. This narrative review summarizes current evidence regarding the biological activities of butyrate and its potential therapeutic relevance in sepsis and septic shock. A comprehensive literature search of PubMed and additional sources up to April 2025 identified experimental and clinical studies evaluating butyrate supplementation in sepsis. Preclinical studies show that butyrate improves function across organ systems (neurologic, hepatic, intestinal, cardiac, pulmonary, and renal) mainly by reducing inflammation, oxidative stress, and epithelial barrier disruption. In models like cecal ligation and puncture (CLP) or endotoxemia, survival improved by 20–40 % with butyrate administration. Human data are limited: an observational study found higher circulating β-hydroxybutyrate levels in sepsis survivors, while a randomized trial reported fewer gastrointestinal complications and ventilator-associated pneumonia in patients with synbiotic-induced butyrate increases. Overall, current evidence suggests that butyrate may modulate key pathophysiological pathways in sepsis and holds potential as an adjunctive therapy. Nonetheless, dedicated early-phase clinical trials are required to clarify safety, optimal dosing, pharmacodynamics, and clinical effectiveness
Creativity, the fountain of youth: Association between creativity and semantic memory networks across the lifespan
No full textCreativity relies on the ability to make new associations between concepts stored in our semantic memory in order to create new and effective ideas in a specific context. Recent studies showed that creative people are characterized by more flexible semantic memory structures, which facilitate novel associations between con- cepts. On the other hand, older adults exhibit more rigid semantic memory structures and ability to access these structures, raising questions about how the relationship between semantic memory networks and creativity may change with ageing. Can creativity support a more flexible reconstruction of semantic memory network during ageing? To investigate this, 77 older adults (M = 77.8 years, SD = 4.63) and 81 younger adults (M = 20.3 years, SD = 1.71) completed four verbal production tasks (i.e., two verbal fluency and two free association tasks), from which semantic memory networks were estimated. Moreover, two divergent thinking tasks (i.e., Alternative Uses Task) were used to assess creative performance. The results showed that the typical maturation of older adults’ semantic memory network is associated with a decrease in creative performance in comparison to younger adults. On the other hand, higher creative older adults exhibited preservation of their overall semantic memory flexibility in comparison to lower creative older adults, similar to lower creative young adults. Overall, this study highlights the potential protective role of creativity in supporting active ageing through its propaedeutic role in maintaining a flexible organization and access to semantic memory structures
30-day postoperative mortality and the effects of hospital preparedness during the COVID-19 pandemic: a pooled analysis of prospective international cohort studies
No full textBackground: Surgical services were poorly prepared for the COVID-19 pandemic, leading to widescale disruption to elective activity. This study aimed to identify actionable priorities to strengthen pandemic preparedness of surgical and hospital systems. Methods: This study pooled data from three international, prospective cohort studies including patients who had a positive SARS-CoV-2 test result in the seven days before or within 30 days after surgery. Patients were included across four pandemic time periods: Period 1 (January-May 2020), Period 2 (June-July 2020), Period 3 (October 2020), and Period 4 (December-March 2022). The primary outcome measure was 30-day postoperative mortality. Hierarchical logistic regression models were developed to explore association between pandemic periods (primary analysis) and hospital-level preparedness (secondary analysis) on 30-day postoperative mortality. Hospital preparedness was classified in to poorly-, moderately-, and highly-prepared tertiles based on Surgical Preparedness Index (SPI) score. Findings: A total of 31,751 patients were included from 1589 hospitals and 102 countries. From Period 1 through to Period 4 there was a decrease in the proportion of patients aged ≥70 years and with ASA grades 3-5.30-day postoperative mortality fell from Period 1 (18.4% [1378/7502]), Period 2 (9.9% [219/2234], adjusted odds ratio (aOR) 0.65, 95% confidence interval (CI) 0.53-0.78), Period 3 (10.5% [246/2427], aOR 0.60, 95% CI 0.50-0.71), through to Period 4 (5.8% [1132/19,588], aOR 0.33, 95% CI 0.30-0.37). During Period 4, SARS-CoV-2 vaccinated patients had lower mortality compared to unvaccinated patients (4.9% [603/12,361] versus 7.4% [529/7178], aOR 0.49, 95% CI 0.42-0.57). Compared to poorly-prepared hospitals (11.2% [1019/9071]), moderately-prepared (9.4% [857/9071], aOR 0.84, 95% CI 0.75-0.94) and highly-prepared hospitals (5.8% [530/9071], aOR 0.70, 95% CI 0.62-0.80) had lower mortality. Interpretation: Postoperative mortality decreased over the course of the COVID-19 pandemic and was lower in better prepared hospitals. Hospitals are critical national infrastructure and strengthening their preparedness by developing formal pandemic plans, establishing patient and procedure prioritisation protocols, and ring-fencing surgical beds would ensure safer surgical care during future pandemics. Funding: National Institute for Health and Care Research, United Kingdom
Intelligenza artificiale e formazione: perché e come imparare e insegnare oggi?
No full textLa diffusione dei sistemi di intelligenza artificiale, che oggi sono entità a comportamento appreso e sempre più cognitivamente sofisticato, ci sta sollecitando a interrogarci sull’adeguatezza dei nostri modelli formativi. A partire da un’analisi sul ruolo degli strumenti tecnici nella formazione, si evidenzia la criticità di una formazione orientata unicamente alla trasmissione di contenuti e all’uso di strumenti, proponendo invece che l’obiettivo dei docenti potrebbe essere di promuovere lo sviluppo delle attitudini e della cultura degli studenti mediante i contenuti
Safety and equity in scaling minimally invasive surgery worldwide in 109 countries using cholecystectomy as a tracer procedure: a prospective cohort study
No full textBACKGROUND: Minimally invasive surgery is rapidly expanding globally, yet there is insufficient knowledge of how to scale this technology safely and equitably across diverse health systems. We aimed to identify health-system factors associated with safe implementation of minimally invasive surgery globally, using minimally invasive cholecystectomy as a tracer procedure. METHODS: We conducted a multicentre, prospective cohort study of consecutive adults undergoing cholecystectomy between July 31 and Nov 19, 2023, in 1218 hospitals across 109 countries. Data were collected by more than 10 000 health-care workers using a core measurement set mapped to the WHO Health System Building Blocks and the Global Patient Safety Action Plan. The primary outcome was 30-day procedure-specific complications, with multilevel logistic regression used to examine associations between health-system features and patient outcomes. This study is registered on ClinicalTrials.gov (NCT06223061). FINDINGS: Among 52 187 included patients, the adjusted procedure-specific complication rate varied 40-fold between hospitals, from 0·3% in the lowest risk quintile to 12·1% in the highest risk quintile. Despite large structural differences across income groups in access to minimally invasive surgery, diagnostics, and emergency services, country income level was not independently associated with complication rates (adjusted odds ratio [OR] 0·81 [95% CI 0·59-1·10] for upper-middle income vs high income and 0·99 [0·70-1·39] for lower-middle income or low income vs high income). Three modifiable hospital-level factors were strongly associated with safer outcomes: establishment of local simulation-based training facilities (adjusted OR 0·78 [0·71-0·86]; p<0·0001), adoption of intraoperative safety and communication strategies (0·87 [0·79-0·96]; p=0·0046), and on-site CT diagnostics (0·79 [0·65-0·97]; p=0·0220). Training facilities showed the greatest benefit in hospitals with limited infrastructure and an inexperienced workforce: the number needed to treat to prevent a procedure-specific complication was 21 (95% CI 14-35; p<0·0001). INTERPRETATION: Safe implementation of minimally invasive surgery varies widely worldwide but is not defined by national income level; differences in outcomes reflect the ability of health systems to adopt and safely deploy new surgical techniques. We identified for the first time that the presence of local simulation-based training facilities is independently associated with improved patient outcomes. Simulation appears to be fundamental to the safe delivery of minimally invasive surgery, particularly in resource-constrained settings. Together with safety systems and diagnostic capacity, these findings offer actionable targets for health systems seeking to equitably scale up essential surgical technologies
Tiny Tools, Great Potential: Innovation in Carbon and Gold Nanostructures
No full textLe nanostrutture di carbonio e oro sono tra gli esempi più iconici di nanotecnologie. Le loro eccezionali proprietà su scala nanometrica sono state ampiamente studiate per decenni. Tuttavia, il potenziale di questi minuscoli strumenti non è ancora stato completamente sfruttato. Tra questi, i Carbon Nanodots (CNDs) presentano proprietà affascinanti. Definiti come nanoparticelle a base di carbonio di dimensioni inferiori a 10 nm, i CNDs si distinguono per la loro fotoluminescenza, biocompatibilità, ricca chimica di superficie ed elevata solubilità, caratteristiche che li rendono promettenti per un ampio spettro di applicazioni. D’altra parte, i nanorods d’oro (Au NRs), grazie alle loro interessanti proprietà ottiche e catalitiche, rivestono un ruolo fondamentale in diversi sistemi biomedici, dispositivi nanofotonici e catalizzatori. Il lavoro presentato in questa tesi mira a far avanzare lo stato dell’arte nella ricerca sui CNDs e sui Au NRs, aprendo a nuove possibilità. Inoltre, la tesi è organizzata in tre capitoli: Il Capitolo 1 si concentra su un’introduzione generale agli argomenti trattati nella tesi, relativi alle nanostrutture di carbonio ed oro.
Nel Capitolo 2 si affrontano le problematiche legate alla sintesi e al meccanismo di formazione dei CND. Infatti, tali meccanismi risultano ancora poco compresi, ostacolando un controllo accurato del processo di sintesi. Inoltre, i metodi di sintesi tradizionali presentano spesso una bassa riproducibilità, un controllo dimensionale limitato e un difficile scale-up, a causa di trasferimenti irregolari di calore e massa nell’ambiente di reazione. Questo progetto affronta tali criticità attraverso due approcci distinti. Il primo consiste nell’indagine degli intermedi molecolari che si formano nei primi istanti della sintesi dei CND a partire da L-arginina ed etilendiammina. Mediante separazione cromatografica, risonanza magnetica nucleare e spettrometria di massa, sono stati isolati e caratterizzati diversi intermedi chiave, fornendo nuovi spunti sul meccanismo di formazione dei CND. Il secondo approccio prevede l’impiego della tecnologia a laser infrarosso (IR) in sostituzione del riscaldamento a microonde, con l’obiettivo di generare elevati gradienti termici, che potrebbero contribuire a superare alcune limitazioni della sintesi CND convenzionale. Tuttavia, i test iniziali hanno evidenziato alcune limitazioni dovute a tempi e temperature di riscaldamento insufficienti, limitati dal punto di ebollizione dei solventi e dai tempi di residenza ridotti all’interno della finestra di irraggiamento.
Nel Capitolo 3 vengono presentati risultati preliminari sull’implementazione di nanostrutture d’oro chirali in catalisi eterogenea asimmetrica. Recentemente, i Au NRs con forme chirali sono stati sintetizzati utilizzando induttori chirali come aminoacidi o soluzioni micellari chirali. La geometria dissimmetrica di questi nanomateriali potrebbe conferire un’attività catalitica asimmetrica. Tuttavia, l’applicazione di questi sistemi in catalisi asimmetrica è ancora mancante in letteratura. Per questo motivo, il presente lavoro si concentra sullo sviluppo di nanocatalizzatori d’oro in soluzioni colloidali per la sintesi organica enantioselettiva. A tal fine, sono stati sintetizzati Au NRs chirali mediante crescita chemical-driven e successivamente rivestiti di platino attraverso un innovativo metodo micelle-directed, ottenendo nanorods d’oro chirali con uno strato di platino uniformemente distribuito. I nanomateriali ottenuti sono risultati capaci di promuovere la reazione di idrogenazione di un composto prochirale (methylphenyl glyoxylate) ma non è stata osservata alcuna attività catalitica asimmetrica.Carbon and gold nanostructures are two of the most iconic examples of nanotechnology. Their exceptional properties at nanoscale have been extensively investigated for decades. However, the potential of these tiny tools is not yet fully exploited. Among these, Carbon Nanodots (CNDs) exhibit fascinating properties. CNDs are defined as carbon-based nanoparticles smaller than 10 nm, and they stand out for strong photoluminescence, biocompatibility, versatile surface chemistry, and excellent solubility, making them highly promising for a wide range of applications. On the other hand, Gold Nanorods (Au NRs), thanks to their intriguing tunable optical features and versatile catalytic properties, play an integral role in various biomedical systems, nanophotonic devices, and catalysis. The work presented in this thesis aims to advance the state of the art in CND and Au NR research, opening to new possibilities. Additionally, the thesis is organized in three chapters: Chapter 1 provides a general introduction to the topics of this thesis, specifically related to carbon and gold nanotechnology.
In Chapter 2, the issues about the synthesis and formation mechanism of CNDs are discussed. In fact, CND formation mechanisms remain poorly understood, hindering a controlled synthesis. Additionally, traditional preparation methods often suffer from low reproducibility, poor size control, and limited scalability due to irregular heat and mass transfer in reaction vessels. This project addresses these challenges in two ways. First, it investigates the molecular intermediates formed during CND synthesis from L-arginine (Arg) and ethylenediamine (EDA). Through chromatographic separation, nuclear magnetic resonance, and mass spectrometry, several crucial intermediates were isolated and structurally characterized, offering new mechanistic insights into CND formation. Specifically, the project investigates replacing microwave heating with infrared (IR) laser technology to generate rapid and uniform heating gradients, which may help overcome certain limitations of conventional CND synthesis. However, initial tests showed limitations due to insufficient heating time and temperature, constrained by boiling points and short residence times over the irradiation window.
Chapter 3 presents preliminary findings on the use of chiral gold nanostructures in asymmetric heterogeneous catalysis. Recently, chiral-shaped gold nanorods (Au NRs) have been synthesized using inducers such as amino acids or chiral micellar solutions. The unique dissymmetric geometry of these nanomaterials holds potential for enabling asymmetric catalytic activity. However, a comprehensive understanding and practical application of colloidal asymmetric nanocatalysis remain limited. This study, therefore, aims to advance colloidal gold nanocatalysis for enantioselective organic synthesis. To achieve this, chiral gold nanorods were synthesized through chemically driven dissymmetric growth, followed by coating with platinum via a novel micelle-directed approach, resulting in Au@Pt nanorods featuring a uniform platinum shell. These chiral Au@Pt nanorods were found to be able to promote the hydrogenation of a prochiral substrate, methylphenyl glyoxylate, but no enantioselective catalytic activity was detected
Esposizione per via aerea, contaminazione cutanea e assorbimento attraverso la pelle di arsenuro di gallio e altri metalli in dimensioni nanometriche.
No full textQuesto progetto di ricerca ha valutato l’esposizione professionale a nanoparticelle (NP) di arseniuro di gallio (GaAs) e ha indagato il rischio di assorbimento transdermico di NP di GaAs e di punti quantici (QD) di solfuro di cadmio (CdS) tramite studi ex-vivo con celle di diffusione Franz.
Il monitoraggio iniziale ha rilevato una concentrazione media complessiva di nanoparticelle di GaAs nell’aria pari a 1045 np/cm3 durante le operazioni di laboratorio, con picchi transitori fino a 88883 particelle/cm3 durante il taglio meccanico dei wafer. Le concentrazioni medie settimanali di Ga e As nell’aria erano rispettivamente di 118,07 ng/m3 e 44,58 ng/m3. È stata rilevata una contaminazione superficiale significativa, con un picco all’interno delle cappe aspiranti (Ga max: 3308 ng/cm2). Il monitoraggio biologico ha mostrato che l’arsenico urinario medio (19,5 μg/L) superava l’intervallo di riferimento per soggetti non esposti (2,0–15 μg/L).
Una successiva campagna di monitoraggio, dopo l’implementazione di protocolli di pulizia avanzati e l’uso rigoroso di dispositivi di protezione individuale (DPI), ha dimostrato un’elevata efficacia: le concentrazioni cutanee di arsenico e gallio sono diminuite rispettivamente del 95% e di oltre il 99,8%, confermando il successo delle misure amministrative e ingegneristiche adottate.
Gli studi ex-vivo hanno ulteriormente quantificato il rischio cutaneo. Per il GaAs, la pelle umana intatta si è dimostrata una barriera altamente efficace, con una permeazione molto bassa sia per Ga che per As. Al contrario, la pelle meccanicamente danneggiata ha mostrato un assorbimento significativamente maggiore. Dopo 24 ore, le concentrazioni di arsenico nel compartimento ricevente erano 38 volte superiori nella pelle danneggiata (1558 ± 546 ng/cm2) rispetto a quella intatta (41 ± 33,4 ng/cm2) (p < 0,05). Anche le concentrazioni di gallio sono aumentate in modo simile, risultando 15 volte superiori nella pelle danneggiata (244 ± 5,29 ng/cm2) rispetto a quella intatta (16,3 ± 1,56 ng/cm2) (p < 0,05).
Analogamente, gli studi sui QD di CdS hanno confermato che l’integrità cutanea è fondamentale: la pelle intatta ha mostrato una permeazione minima, mentre la pelle danneggiata ha evidenziato un assorbimento significativo e dipendente dalla dimensione. La pelle intatta ha assorbito quantità minime di Cd: 4,07 μg/cm2 (3,4 nm), 13,67 μg/cm2 (5,8 nm) e 4,56 μg/cm2 (6,7 nm). La pelle danneggiata ha mostrato un assorbimento molto più elevato: 302,87 μg/cm2 (3,4 nm), 121,56 μg/cm2 (5,8 nm) e 11,34 μg/cm2 (6,7 nm), confermando che l’integrità della pelle è un fattore critico nel limitare la penetrazione delle nanoparticelle e l’esposizione sistemica.This research project assessed occupational exposure to Gallium Arsenide (GaAs) nanoparticles (NPs) and investigated the transdermal absorption risk of GaAs NPs and Cadmium Sulfide (CdS) Quantum Dots (QDs) via ex-vivo Franz diffusion cells.
Initial monitoring revealed an overall average airborne GaAs nanoparticle concentration of 1045 np/cm3 during active operations, but transient peaks reached 88883 particles/cm3 during mechanical wafer cutting. Weekly average airborne concentrations were measured at 118.07 ng/m3 for Gallium (Ga) and 44.58 ng/m3 for Arsenic (As). Significant surface contamination was detected, peaking inside fume hoods (Ga max: 3308 ng/cm2). Biological monitoring showed average urinary arsenic (19.5 μg/L) exceeded the non-occupational reference range (2.0–15 μg/L).
A subsequent monitoring campaign, following the implementation of enhanced cleaning and rigorous Personal Protective Equipment (PPE) protocols, demonstrated high effectiveness: dermal arsenic and gallium concentrations dropped by 95% and over 99.8%, respectively, confirming the success of administrative and engineering controls.
The ex-vivo studies further quantified dermal hazard. For GaAs, intact human skin proved to be a highly effective barrier, demonstrating very low permeation for both Ga and As. In stark contrast, mechanically damaged skin significantly enhanced absorption. After 24 hours, arsenic concentrations in the receptor compartment were thirty-eight times higher in damaged skin (1558 ± 546 ng/cm2) compared to intact skin (41 ± 33.4 ng/cm2) (p < 0.05). Gallium concentrations similarly increased, being fifteen times higher in damaged skin (244 ± 5.29 ng/cm2) than in intact skin (16.3 ± 1.56 ng/cm2) (p < 0.05).
Similarly, CdS QD studies confirmed skin integrity is fundamental, showing minimal permeation through intact skin but significant, size-dependent absorption through damaged skin. Intact skin showed minimal Cd absorption: 4.07 μg/cm2 (3.4 nm), 13.67 μg/cm2 (5.8 nm), and 4.56 μg/cm2 (6.7 nm) in receptor fluid. Damaged skin showed significantly higher uptake: 302.87 μg/cm2 (3.4 nm), 121.56 μg/cm2 (5.8 nm), and 11.34 μg/cm2 (6.7 nm), confirming that skin integrity critically limits nanoparticle penetration and systemic exposure