Search Results (807)

Reinforcing PLA composites with natural fibres is a prominent strategy for improving PLA’s properties while benefiting from its intrinsic biodegradation. However, these composites may be susceptible to an inefficient stress-transferring process due to the weak intermolecular interactions between PLA and natural fibres. A well-known practice is to incorporate coupling agents to improve polymer–fibre adhesion, such as carboxylic acids (CAs) and grafted copolymers. CAs are a more affordable and biodegradable option for improving PLA/natural fibre interface strength, resulting in a material with superior mechanical and thermal properties. In this context, this research discusses the potential use of mono (C6 and C8) and di (CC6 and CC8) carboxylic acids as coupling agents in PLA/pecan nutshells (PN) composites. PLA/PN composites with four different CAs were processed in a twin-screw extruder and subsequently injection moulded. The results indicated an increase in the flexural strength of the PLA due to the presence of PN in the neat composite. The use of CAs increased the storage modulus of PLA/PN composites, while C6 and CC8 reduced the PLA composite tan δ peak height. The PLA’s T_g in PLA/PN composite shifted to lower temperatures after the incorporation of CAs while increasing the PLA crystallinity degree. These results strongly suggested that besides acting as efficient coupling agents, these acids also exerted roles as nucleating agents and plasticisers. Full article

This discussion explores the (dis)engagement of Jamaican RastafarI from the party political process, using RastafarI elder Mortimo Planno’s notion of “politics without a party” as a strand shaping and tying together the multiple threads of the exploration. The discussion examines how RastafarI has engaged with partisan politics/political parties from Independence (1962) until today. It highlights the differing ways of approaching politics among Rastas, including the minority, who have entered representative politics in a bid to [as yet unsuccessfully] change the tribal and compromised state of Jamaican politics. The decentralized nature of the RastafarI movement allows for diverse expressions of RastafarI political thought and action, but can present challenges for unified political mobilization on a large scale. Nonetheless, with or without direct partisan involvement, RastafarI has adapted and re-presented itself in response to changes in the local and global context, thus becoming a potent political force. So, despite this general lack of engagement with “statical” matters, RastafarI is and continues to be a significant political movement on several fronts, through movements, music, and symbols rather than traditional electoral routes. Full article

The artichoke (Cynara cardunculus L. subsp. scolymus) is an endemic perennial plant of the Mediterranean area commonly consumed as food. It is known since ancient times for its beneficial properties for human health, among which its antioxidant activity due to polyphenolics stands out. In the frame of our ongoing studies aiming to highlight the biodiversity and the chemodiversity of natural resources, we investigated the phenolic and saponin content of the cultivar “Carciofo di Procida” collected at Procida, an island of the Gulf of Naples (Italy). Along with the edible part of the immature flower, we included in our analyses the stem and the external bracts, generally discarded for food consuming or industrial preparations. The LCMS quali-quantitative profiling of polyphenols (including anthocyanins) and cynarasaponins of this cultivar is reported for the first time. In addition to antioxidant properties, we observed a significant cytotoxic activity due to extracts from external bracts against human neuroblastoma SH-SY5Y cell lines with 43% of cell viability, after 24 h from the treatment (50 μg/mL), and less potent but appreciable effects also against human colorectal adenocarcinoma CaCo-2 cells. This suggests that the different metabolite composition may be responsible for the bioactivity of extracts obtained from specific parts of artichoke and foresees a possible exploitation of the discarded material as a source of beneficial compounds. Full article

Multivalent lectin–glycan interactions (MLGIs) are vital for viral infection, cell-cell communication and regulation of immune responses. Their structural and biophysical data are thus important, not only for providing insights into their underlying mechanisms but also for designing potent glycoconjugate therapeutics against target MLGIs. However, such information remains to be limited for some important MLGIs, significantly restricting the research progress. We have recently demonstrated that functional nanoparticles, including ∼4 nm quantum dots and varying sized gold nanoparticles (GNPs), densely glycosylated with various natural mono- and oligo- saccharides, are powerful biophysical probes for MLGIs. Using two important viral receptors, DC-SIGN and DC-SIGNR (together denoted as DC-SIGN/R hereafter), as model multimeric lectins, we have shown that α-mannose and α-manno-α-1,2-biose (abbreviated as Man and DiMan, respectively) coated GNPs not only can provide sensitive measurement of MLGI affinities but also reveal critical structural information (e.g., binding site orientation and mode) which are important for MLGI targeting. In this study, we produced mannuronic acid (ManA) coated GNPs (GNP-ManA) of two different sizes to probe the effect of glycan modification on their MLGI affinity and antiviral property. Using our recently developed GNP fluorescence quenching assay, we find that GNP-ManA binds effectively to both DC-SIGN/R and increasing the size of GNP significantly enhances their MLGI affinity. Consistent with this, increasing the GNP size also significantly enhances their ability to block DC-SIGN/R-augmented virus entry into host cells. Particularly, ManA coated 13 nm GNP potently block Ebola virus glycoprotein-driven entry into DC-SIGN/R-expressing cells with sub-nM levels of EC₅₀. Our findings suggest that GNP-ManA probes can act as a useful tool to quantify the characteristics of MLGIs, where increasing the GNP scaffold size substantially enhances their MLGI affinity and antiviral potency. Full article

Background and Objectives: Digoxin is a pharmacological agent of natural origin that is still occasionally administered in the intensive care unit (ICU). The objective of this study was to assess the efficacy of routine therapeutic drug monitoring (TDM) of digoxin in ICU patients with heart failure. Materials and Methods: This retrospective, single-center study was conducted using data from the ICU database of the Silesian Center for Heart Diseases in Zabrze, Poland. A total of 980 ICU admissions between January 2018 and July 2023 were screened, and 103 patients met the inclusion criteria. Patients were excluded if they had not received digoxin during hospitalization, had only one digoxin level measurement, or did not meet the established criteria for heart failure. Results: Women required significantly lower doses of digoxin compared to men (0.171 ± 0.053 mg vs. 0.224 ± 0.080 mg; p < 0.001). Patients who died had significantly higher serum digoxin concentrations than survivors (1.33 ± 0.59 ng/mL vs. 1.03 ± 0.43 ng/mL; p = 0.003). Similarly, patients with liver failure had higher digoxin levels compared to those without liver dysfunction (1.31 ± 0.58 ng/mL vs. 1.06 ± 0.46 ng/mL; p = 0.016). A weak negative correlation was found between age and the administered dose (r = −0.20; p = 0.048), and a weak positive correlation was observed between serum digoxin concentration and NT-proBNP levels (r = 0.23; p = 0.048). Conclusions: Among ICU patients with multi-organ failure, those with concomitant liver dysfunction tended to reach higher serum digoxin concentrations. Routine therapeutic drug monitoring of digoxin in ICU patients appears beneficial and may help to optimize dosing and reduce adverse effects. Full article

As semiconductor devices demand higher input–output density and faster signal transmission, fan-out panel-level packaging has emerged as a promising solution for next-generation electronic systems. However, the hygroscopic nature of epoxy molding compounds raises critical reliability concerns under high-temperature and high-humidity conditions. This study investigates the hygrothermal stress of a single fan-out panel-level package unit through experimental characterization and numerical simulation. Thermal–mechanical analysis was conducted at 100 °C and 260 °C to evaluate the strain behavior of two commercial epoxy molding compounds in granule form after moisture saturation. The coefficient of moisture expansion was calculated by correlating strain variation with moisture uptake obtained under 85 °C and 85% relative humidity, corresponding to moisture sensitivity level 1 conditions. These values were directly considered into a moisture -thermal coupled finite element analysis. The simulation results under reflow conditions demonstrate accurate principal stress and failure location predictions, with stress concentrations primarily observed at the die corners. The results confirm that thermal effects influence stress development more than moisture effects. Finally, a structural sensitivity analysis of the single-package configuration showed that optimizing the thickness of the dies and epoxy molding compound can reduce maximum principal stress by up to 12.4%, providing design insights for improving package-level reliability. Full article

The climate crisis poses profound risks to present and future generations. Nonetheless, the perspectives of children and young people internationally, and more specifically in Brazil, remain underexplored. Based on a multi-discipline literature review on climate anxiety and nature (dis)connectedness, the hypothesis is that the effects and symptoms of increasing (dis)connection with natural environments have short-, medium-, and long-term consequences. Access to natural spaces is a vital response to counteract the negative impacts of climate change. This article discusses findings from a study conducted in urban Brazil with 200 young people aged 12 to 18 years old, with the aim of addressing three research questions from ten questions that comprised the complete survey. The major research questions were as follows: 1. ‘Climate change worries me’: How do you relate to this statement? 2. How does climate change affect you?, and 3. Do you think some young people are more affected by climate change than others? The results show that young people care about and are preoccupied with climate change, especially when they reflect on their futures and the future generations. Although young participants are deeply concerned about climate change and feel its effects personally in the form of anxiety, fear, and insecurity, they often lack clear pathways for contributing to broader environmental efforts beyond individual actions. These findings highlight an urgent need to foster community-based approaches and enhance education and resources for enlarging and improving youth engagement, especially to rethink the everyday strategies addressing these challenges, and to foster new paradigms of interaction with the natural world based on (re)connection with natural spaces. The correlation between climate anxiety and nature (dis)connection offers an approach that is still little explored, especially concerning children and young people. Full article

Pseudomonas aeruginosa biofilm formation is critical to antibiotic resistance and persistence. Targeting cyclic di-GMP (c-di-GMP) signaling, a master biofilm formation and virulence regulator, presents a promising strategy to combat resistant bacterial infections. Myricetin, a natural polyphenolic flavonoid with documented antimicrobial and anti-biofilm activities, may enhance antibiotic efficacy against Pseudomonas aeruginosa. This study evaluated the synergistic effects of myricetin combined with azithromycin, ciprofloxacin, or cefdinir against both standard and drug-resistant Pseudomonas aeruginosa strains. Antibacterial activity, biofilm disruption, and motility inhibition were experimentally assessed, while molecular dynamic (MD) simulations elucidated myricetin’s molecular mechanism of action. Our results suggested that myricetin synergistically potentiated all three antibiotics, reducing c-di-GMP synthesis by 28% (azithromycin), 57% (ciprofloxacin), and 30% (cefdinir). It enhanced bactericidal effects, suppressed biofilm formation, and impaired swimming, swarming, and twitching motility. Computational analyses revealed that myricetin binds allosterically to FimX very well, a key regulator in the c-di-GMP signaling pathway. Hence, myricetin may act as a c-di-GMP inhibitor, reversing biofilm-mediated resistance in Pseudomonas aeruginosa and augmenting antibiotic efficacy. This integrated experimental and computational approach provides a framework for developing anti-virulence and antibiotic combination therapies against recalcitrant Gram-negative pathogens. Full article

During the service life of automotive panel stamping dies, the surface is often subjected to high loads and repeated friction, resulting in excessive wear. This leads to die failure, reduced machining accuracy, and decreased production efficiency. To enhance the anti-friction and wear-resistant performance of die steel surfaces, this study introduces the concept of biomimetic engineering in surface science. By mimicking microstructural configurations found in nature with outstanding wear resistance, biomimetic functional surfaces were designed and fabricated. Specifically, quadrilateral dimples inspired by the back of dung beetles, pentagonal scales from armadillo skin, and hexagonal scales from the belly of desert vipers were selected as biological prototypes. These surface textures were fabricated on Cr12MoV die steel using high-speed ball-end milling. Finite element simulations and dry sliding wear tests were conducted to systematically investigate the tribological behavior of surfaces with different dimple geometries. The results showed that the quadrilateral dimple surface derived from the dung beetle exhibited the best performance in reducing friction and wear. Furthermore, the milling parameters for this surface were optimized using response surface methodology. After optimization, the friction coefficient was reduced by 21.3%, and the wear volume decreased by 38.6% compared to a smooth surface. This study confirms the feasibility of fabricating biomimetic functional surfaces via high-speed ball-end milling and establishes an integrated surface engineering approach combining biomimetic design, efficient manufacturing, and parameter optimization. The results provide both theoretical and methodological support for improving the service life and surface performance of large automotive panel dies. Full article

This study investigates the behavior of spark discharges under various environmental conditions to simulate aspects of early-stage lightning dynamics, with a focus on their spectral characteristics, propagation, and ionization behavior. In a laboratory setting, spark discharges generated by a Tesla coil operating with high-frequency alternating current (AC) were analyzed under varying air humidity and water surface conductivity. Spectral analysis revealed that the discharges are dominated by the second positive system of molecular nitrogen N₂ (2P) and also exhibit the first negative system of molecular nitrogen ions N₂⁺ (1N). Notably, the N₂ (2P) emissions show strong peaks in the 350–450 nm range, closely matching spectral features typically associated with corona and streamer discharges in natural lightning. Environmental factors significantly influenced discharge morphology: in dry air, sparks exhibited longer and more branched paths, while in moist air, the discharges were shorter and more confined. Over water surfaces, the sparks spread radially, forming star-shaped patterns. Deionized (DI) water, with low conductivity, supported wider lateral propagation, whereas higher conductivity in tap water and saltwater suppressed discharge spread. The gap between the electrode tip and the surface also affected discharge extent and brightness. These findings demonstrate that Tesla coil discharges reproduce key features of early lightning processes and offer insights into how environmental factors influence discharge development. Full article

The semi-synthesis of the (5R,7R,11bR)-9-(di(1H-indol-3-yl)methyl)-4,4,7,11b-tetramethyl-1,2,3,4,4a,5,6,6a,7,11,11a,11b-dodecahydrophenanthro[3,2-b]furan-5-yl acetate was performed via a pseudo-multicomponent reaction involving a double Friedel–Crafts alkylation between the natural product-derived aldehyde 6β-acetoxyvouacapane and the corresponding indole. The transformation was carried out under solvent-free mechanochemical conditions using mortar and pestle grinding, with ZnCl₂ as the catalyst. Structural elucidation of the target compound was accomplished using 1D and 2D NMR spectroscopy (¹H, ¹³C, COSY, HSQC, and HMBC), FT-IR, and high-resolution mass spectrometry (HRMS). Full article

Background/Objectives: Natural oils are widely promoted and used around the world as part of skincare. Among them, extra virgin olive oil (EVOO) stands out for its broad range of organic compositions and well-known moisturizing properties. This study aimed to evaluate the effects of topically applied EVOO compared to petrolatum on skin barrier function (SBF) and microtopography. Methods: A within-person randomized clinical trial was conducted in healthy adult volunteers. EVOO and petrolatum were applied to defined areas on the volar forearm. Parameters related to the SBF, including stratum corneum hydration (SCH), transepidermal water loss (TEWL), temperature, and erythema, were assessed. The skin microtopography was evaluated through two approaches: (1) topographic parameters—surface roughness, desquamation, smoothness, and wrinkles; and (2) stratum corneum (SC) composition—corneocytes subtypes and the desquamation index (DI). The participants completed a tolerability questionnaire for each product. Results: A total of 54 participants (50% female; mean age: 28.57 ± 11.02 years) completed the study. Both EVOO and petrolatum significantly improved the SBF by increasing SCH and reducing erythema and skin temperature. Petrolatum additionally reduced TEWL. Regarding the skin microtopography, both products decreased the desquamation index and reduced the prevalence of mature corneocyte types (types 2–5). These effects were more pronounced with petrolatum. Notably, EVOO significantly increased the proportion of early-stage corneocytes (type 1). Conclusions: Both EVOO and petrolatum effectively enhanced the SBF and improved the microtopographic features of the skin. While petrolatum exerted a stronger occlusive effect by reducing TEWL and desquamation, EVOO uniquely promoted epidermal renewal by increasing epidermal turnover. Full article

Nowadays, healthcare systems face two global challenges: the rise of multidrug-resistant pathogens and the growing incidence of cancer. Due to their broad spectrum of activities, antimicrobial peptides emerged as potential alternatives against both threats. Our group previously described the antifungal activity of the α-helical peptide Cm-p5, a derivative of the natural peptide Cm-p1, isolated from the coastal mollusk Cenchritis muricatus; however, its anti-cancer properties remained unexplored. Analyses through calorimetry and molecular dynamics simulations suggest the relevance of phosphatidylserine for the attachment of Cm-p5 to cancer cell membranes. Cm-p5 exhibited cytotoxic activity in a dose-dependent manner against A375 melanoma cells, without toxicity against non-malignant cells or hemolytic activity. DAPI/PI and DiSC3(5) staining confirmed permeabilization, disruption, and depolarization of A375 cytoplasmic membranes by Cm-p5. Furthermore, Annexin V-FITC/PI assay revealed the induction of cellular death in melanoma cells, which can result from the cumulative membrane damage and oxidative stress due to the overproduction of reactive oxygen species (ROS). Moreover, after the treatment, the proliferation of A375 cells was dampened for several days, suggesting that Cm-p5 might inhibit the recurrence of melanomas. These findings highlight the multifunctional nature of Cm-p5 and its potential for treating malignant melanoma. Full article

Background: The rise in multidrug-resistant bacteria has intensified the search for new antibiotics, drawing attention to essential oils (EOs) for their antimicrobial properties. For this reason, this study focuses on the antimicrobial action of the EO obtained from Tagetes minuta and its impact on bacterial membranes. Methods: The EO was chemically characterized by chromatography–mass spectrometry, and its antimicrobial activity and its effects on surface and bacterial membrane were assessed by using Zeta potential, membrane transition temperature (Tm) determination; and fluorescence spectroscopy with Laurdan and Di-8 ANEPPS. Results: Twenty-seven compounds could be identified, with (E)-Tagetone, (Z)-Ocimenone, and β-pinene as the most abundant. Afterward, the EO was tested against Escherichia coli (MIC and MBC = 17 mg/mL) and Staphylococcus aureus (MIC = 8.5 mg/mL; MBC > 17 mg/mL), showing antimicrobial action in both bacteria, being more effective against E. coli. Mechanistic studies revealed that the EO interacts with bacterial membranes, increasing the Zeta potential by more than 9 mV and enhancing membrane permeability up to 90%. These effects were further confirmed using model lipid membranes, where the EO induced significant changes in membrane properties, including a reduction in dipole potential and transition temperature, suggesting that some EO components could be inserted into the lipid bilayer, disrupting membrane integrity. Conclusions: The EO from T. minuta demonstrates efficient antimicrobial activity by compromising bacterial membrane structure, highlighting its potential as a natural antimicrobial agent. Full article

The presence of cetaceans along the Campania coast has always been documented. Between 2016 and 2022, out of 65 cetaceans stranded along the Campania coast, 46 were studied for bacteriological, virological, parasitological, and histopathological investigations. The results highlighted that for 59% (n = 27) of the specimens, the cause of death was of natural origin, while for only 2% (n = 1) of animals, the origin of death was ascribed to anthropic causes. Unfortunately, for 39% (n = 18) of the cetaceans, it was impossible to determine the cause of death. All the cetaceans that died of natural causes showed viral, bacterial, and parasitic infections. The primary pathogens detected were Cetacean Morbillivirus (CeMV, 65.2%, n = 30/46), Toxoplasma gondii (10.9%, n = 5/46), and Brucella ceti (8.7%, n = 4/46). The animals showed typical lesions of the isolated pathogens, such as systemic infection, meningoencephalitis, and pneumonia. Moreover, even with a lower frequency, other relevant pathogens like Photobacterium damselae, Salmonella enteritidis, Erysipelothrix rhusiopathiae, and Chlamydia abortus were isolated. These data were useful to understand the spread and circulation of these pathogens, some zoonotic, in the coastal marine waters of the Campania region. Full article