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Hydrothermal synthesis of Cu/Pr doped and Co-doped fluorapatite for biomedical applications: Antibacterial efficiency and cytotoxicity assessment
No full textIn this study, Cu2+ and Pr3+doped Fluorapatite (FAP) nanoparticles were successfully synthesized via a hydrothermal method. Their structural, optical, cytotoxic, and antibacterial properties were systematically investigated. X-ray diffraction (XRD) confirmed the preservation of the whole hexagonal fluorapatite structure upon doping and co-doping with Cu2+ and Pr3+ ions, with crystallite sizes estimated using the Scherrer equation as 21.6 nm for pure FAP, 33.7 nm for FAP[sbnd]Cu, 33.0 nm for FAP[sbnd]Pr, and 17.9 nm for co-doped FAP-Pr-Cu. The Williamson–Hall (W[sbnd]H) analysis indicated larger apparent crystallite sizes ranging from 25.2 nm (FAP-Pr-Cu) to 85.5 nm (FAP[sbnd]Cu), suggesting strain-induced peak broadening in the doped samples. Fourier-transform infrared (FTIR) spectroscopy revealed that doping-induced modifications of vibrational modes of fluorapatite matrix and their corresponding intensities, suggesting small structural alterations. By using X-ray photoelectron spectroscopy (XPS), we have confirmed the incorporation of Cu2+ and Pr3+ into the FAP lattice and verified their respective oxidation states. The elemental composition of the prepared powders was investigated by energy dispersive X-ray spectroscopy (EDX). Scanning electron microscopy (SEM) showed agglomerated particles with a sheet-like morphology, while dynamic light scattering (DLS) measurements indicated an increase in the hydrodynamic size upon doping; the average particle sizes ranged from 171.4 nm for pure FAP to 203.0 nm, confirming the impact of dopant incorporation on particle agglomeration. UV–visible absorption spectroscopy revealed a direct bandgap energy of 4.78 eV for pure FAP, whereas the doped samples exhibited bandgap energies ranging between 4.51 eV and 5.40 eV, depending on the doping element. The antibacterial activity was evaluated against clinical bacterial pathogens implicated in oral cavity disease and vagina infection (S1, S2, S3, S4, E1) using the microdilution method. The results demonstrated that Cu[sbnd]Pr co-doped FAP exhibited significantly enhanced antibacterial efficacy against staphylococcus aureus (S1) and Enterococcus faecalis (E1), with minimum inhibitory concentration (MIC) of 0.123 and 1.11 mg/mL, respectively. By contrast, pure FAP was found to have a MIC of 1.11 and 3.33 mg/mL for the same bacteria. Additionally, cytotoxicity assessment on the human osteosarcoma cell line (U2OS) was evaluated using the MTT assay, which indicated that the co-doped sample exhibited lower toxicity
A macroscopic and physically-based relationship between bike speeds and energy expenditure during commuting trips
No full textAs it emerges from the literature, bike speed is a trade-off between safety, travel times, and energy expenditure. In addition to that, infrastructure, terrain, and gender play also a key role. By assessing and correlating energy expenditure with cycling speed, it becomes possible to integrate terrain-related factors with individual human capabilities to gauge effort. This paper gathers terrain-related data from sixty-one (61) German cities and uses it to propose a relationship between energy expenditure and bike speed within a macroscopic, physically grounded framework. Furthermore, a Bike Mode Split (BMS) model is introduced to emphasize the role of energy expenditure in predicting cycling demand, as an application of this physically-based framework. Geographic data, Census data, and mode split data are collected from the main official German sources. The result shows that there is a linear relationship between bike speeds and energy expenditure, and also between energy expenditure and slope for conventional and electrical bike (c-bike, and e-bikes, respectively)
Dancing with the algorithm: a framework to navigate knowledge and autonomy in AI-assisted managerial decisions
Full text linkWhile artificial intelligence (AI) systems (assistive, human-in-the-loop decision support systems) increasingly participate in complex organizational judgments, their integration into knowledge processes raises fundamental challenges for autonomy, trust, and epistemic agency. This study aims to develop a dynamic, phase-specific framework that explains how autonomy evolves in relation to the data–information–knowledge–wisdom (DIKW) hierarchy and foundational knowledge management concepts during AI-assisted managerial decision-making. The study draws on 122 in-depth interviews with senior professionals across diverse sectors, complemented by two expert focus groups. Data were analyzed using the Gioia Methodology to support inductive theory development and generate a grounded conceptual framework. The authors develop the Human–AI autonomy loop (HAIL) framework, mapping decision-making to four recursive phases (frame, evaluate, commit, enact) and DIKW layers, each linked to distinct DIKW layers and autonomy configurations. Autonomy is a situated, distributed practice: managers preserve discretion through interpretive buffers, overrides and moral authorship. Trust in AI is recalibrated by phase, especially as decisions move from information to judgment. HAIL shows that autonomy is sustained through reflexive knowledge practices. This study advances the knowledge management literature by integrating autonomy, trust and epistemic agency into a unified framework of AI-assisted decision-making. It reinterprets the DIKW model not as a linear information hierarchy, but as a socio-technical terrain where knowledge becomes actionable only when embedded in situated judgment and ethical authorship. The HAIL framework offers both theoretical insights and practical guidance for preserving human discretion and organizational wisdom in AI-assisted environments
Biographies of Early Greek Lawgivers in the Suda
No full textThe Byzantine Suda provides biographical lemmata for the archaic Greek lawgivers Lycurgus, Zaleucus, Solon, Pittacus, and Dracon. This paper aims to analyse the main features of these entries, focusing on how individual legislators are characterized, connected to each other, and associated with other wise men and philosophers (e.g., the Seven Sages). The structural elements shared by these entries distin guish them from other lemmata in the Suda on historical figures and contribute to the distinctive nature of this group. For instance, of the three entries dedicated to Solon, the lemma Σ 776 Adler defines him as a ‘philosopher, legislator, and demagogue’ and provides essential information on his life, including his relationship with the tyrant Pisistratus, his exile, and his death. Likewise, Zaleucus is described as a ‘Pythagorean philosopher and lawgiver’ who died ‘fighting for his homeland’ (Ζ 12 Adler). As for Lycurgus of Sparta, while the lemma Λ 823 Adler is very concise, the following entry (Λ 824 Adler) provides many details concerning his biography and the excellent constitution he gave to the Spartans, emphasizing the direct relationship between Sparta’s political success and Lycurgus’ contribution. Thus, this paper thoroughly examines all the entries on the Greek lawgivers to better understand the details given in the Suda, and it also explores the relationship between these biographical headwords and the accounts of the same figures given by Plutarch, Diogenes Laertius, and other parallel sources
Efficacy and safety of European Medicines Agency (EMA)-approved pharmacological, endoscopic, and surgical treatments in different classes of obesity: A network meta-analysis of randomised controlled trials for the development of the SIO (Società Italiana Obesità) Italian guidelines for the diagnosis and treatment of overweight and obesity
Full text linkAims: We aimed at comparing different approved strategies (obesity management medications—OMM, endoscopic bariatric procedures—EBP, and metabolic bariatric surgery—MBS) with lifestyle intervention/placebo/no therapy (LSI/Pbo/NT) for the treatment of different BMI-based classes of obesity (i.e., overweight—BMI: 25–29.9 kg/m2; class I—BMI: 30–34.9 kg/m2; class II—BMI: 35–39.9 kg/m2; class III—BMI >39.9 kg/m2). Materials and Methods: This systematic review (SR) and network meta-analysis (NMA) included randomised clinical trials (RCTs) comparing OMM, EBP, and MBS versus either LSI/Pbo/NT or active comparators in individuals with overweight or obesity. A Medline and Embase search was performed up to 31st January 2025 for RCTs on EMA (European Medicines Agency)-approved weight-loss interventions in adults with overweight/obesity. The primary endpoint was total body weight loss (TBWL%), analysed at different time points: 26–52, 53–104, 105–156, and ≥156 weeks. Secondary endpoints included all-cause mortality, quality of life, and serious adverse events (SAE). Weighted mean difference and 95% confidence intervals (WMD, 95% CI) for continuous variables and Mantel–Haenszel odds ratio (MH-OR, 95% CI) for categorical variables were calculated using random effect models. The study was registered on the PROSPERO website (CRD42024625338). Results: In trials enroling subjects in class I of obesity, tirzepatide resulted in equal effectiveness to both OAGB and RYGB, and it was significantly superior to all the other comparisons. In trials on class II of obesity, tirzepatide was significantly superior to all the other comparisons and inferior to both OAGB and RYGB. Semaglutide was associated with a higher TBWL% than the other OMMs (with the notable exception of tirzepatide), and it was equally effective to EBP, GCP, and LAGB. In trials enroling patients with a mean BMI >40 kg/m2, the procedure with the highest estimated weight loss was BPD. Semaglutide was statistically less effective than SG and gastric bypass, but not inferior to GCP and LAGB. Both RYGB and OAGB were superior to SG. Conclusion: In patients affected by mild to moderate obesity, newer OMMs (i.e., tirzepatide and semaglutide) appear to be valid alternatives to EBP and MBS. They could be preliminarily chosen as a first-line option based on similar efficacy and greater safety and tolerability. Higher degrees of obesity could be more effectively treated with MBS, the efficacy of which, with the notable exception of LAGB and GCP, appears superior to other treatments, especially in the long term
Caspase-8 is a novel modulator of Homologous Recombination Repair in response to ionizing radiations in glioblastoma
Full text linkCaspase-8 is a cysteine protease historically regarded as anti-neoplastic protein, thanks to its role in apoptosis. However, Caspase-8 expression is retained or even enhanced in several tumors, including glioblastoma (GBM), where it plays pro-tumor functions. We previously reported that it is a negative prognostic factor and contributes to resistance against DNA damaging agents, such as ionizing radiations (IR) and Temozolomide, commonly used in standard GBM treatment. We therefore investigated whether Caspase-8 may sustain DNA repair pathways proficiency in GBM. Here we uncover a novel role of Caspase-8 as promoter of the Homologous Recombination Repair (HRR). Importantly, IR promote Caspase-8 transient nuclear translocation and its recruitment to the chromatin. Moreover, Caspase-8 sustains the expression and the recruitment to the chromatin upon IR of RAD51 and CtIP, two key players of the HRR. Consistently, we identify a synthetically lethal interaction between Caspase-8 and PARP inhibition, that may enhance GBM sensitivity to IR. Remarkably, by using Caspase-8−/− murine embryo fibroblasts and a Drosophila melanogaster Caspase-8 mutant, we demonstrate that Caspase-8 plays an evolutionary conserved role in DNA repair
Deterministic diffusion models for Lagrangian turbulence: Robustness and encoding of extreme events
No full textDemonstrating black-diamond-based high-temperature solar cells
Full text linkEfficient high-temperature solar cells are feasible through the photon-enhanced thermionic emission (PETE) mechanism. The development of defect-engineered black-diamond layers, combined with micro-graphitized electrodes fabricated within p-type/intrinsic structures, represents the key technology for sunlight interaction of 0.3-eV electron-affinity PETE diamond cathodes, characterized by excellent electron emission. The resulting PETE converters demonstrate energy generation under concentrated radiation. At operating temperatures ranging from 600 to 900 K, the PETE operational regime is revealed, whereas photoemission and thermionic emission are found to be predominant at lower and higher temperatures, respectively. Cathode thickness emerges as the primary factor limiting the present performance of black-diamond technology. The generation-recombination analytical model applied to the device allows predicting a quantum efficiency of 30.3% for a 300-nm-thick black-diamond cathode operating at 700 K, today attainable with advanced diamond membrane technologies, and a solar-to-electric conversion efficiency of 14.5% for the resulting PETE converter
