Search Results (474)

The Set Coverage Problem (SCP) is an important combinatorial optimization problem known to be NP-complete. The use of metaheuristics to solve the SCP includes different algorithms. In particular, binarization techniques have been explored to adapt metaheuristics designed for continuous optimization problems to the binary domain of the SCP. In this work, we present a new approach to solve the SCP based on the Secretary Bird Optimization Algorithm (SBOA). This algorithm is inspired by the natural behavior of the secretary bird, known for its ability to hunt prey and evade predators in its environment. Since the SBOA was originally designed for optimization problems in continuous space and the SCP is a binary problem, this paper proposes the implementation of several binarization techniques to adapt the algorithm to the discrete domain. These techniques include eight transfer functions and five different discretization methods. Taken together, these combinations create multiple SBOA adaptations that effectively balance exploration and exploitation, promoting an adequate distribution in the search space. Experimental results applied to the SCP together with its variant Unicost SCP and compared to Grey Wolf Optimizer and Particle Swarm Optimization suggest that the binary version of SBOA is a robust algorithm capable of producing high quality solutions with low computational cost. Given the promising results obtained, it is proposed as future work to focus on complex and large-scale problems as well as to optimize their performance in terms of time and accuracy. Full article

Compassion is a critical competence for university students in the healthcare field when dealing with the suffering of patients and relatives. However, there are no tools that measure compassionate capacity during students’ training. Recently, the Compassion Capacity Scale (CCS) was developed for health professionals, exhibiting good psychometric properties. The aim of this study was to translate, culturally adapt, and validate the CCS for Portuguese university students in the healthcare field. The study was divided into two phases: (1) translation and adaptation of the CCS for Portuguese university students in the healthcare field; (2) validation and analysis of psychometric properties. The CCS-PHS showed good internal consistency (Cronbach’s α = 0.886), temporal stability (rho = 0.703), and content validity (CVI-i = 1). Criterion validity analysis showed strong correlations between all of the CCS-PHS’s dimensions and the chosen reference criteria scale. Construct validity analysis revealed that the CCS-PHS is composed of 17 items, classified into four factors. The differences found in the exploratory factor analysis in relation to the original scale may be due to the differences in the life experiences of healthcare professionals when compared to those of students. Our psychometric analysis suggests that the CCS-PHS is a reliable and valid tool to assess compassionate capacity in healthcare students. Knowing the compassionate competence of students is vital for guiding educational strategies, implementing compassion training programs and evaluating their effectiveness, as well as reinforcing key attitudes and behaviors for humanized and ethical healthcare. Full article

Background: Obesity is associated with insulin resistance (IR) and characterized by impaired activation of the PI3K/AKT route and glucose uptake. Elevated plasma levels of palmitic acid (PA) diminish insulin signaling in vitro and in vivo. Origanum vulgare L. essential oil (OVEO) is rich in monoterpenes with protective effects against IR. Objective: The study aimed to assess total phenols content and antioxidant activity of OVEO and its cytotoxicity, as well as its effect on insulin signaling and glucose uptake in PA-treated adipocytes. Methods: The quantification of total phenolic content was determined using the Folin–Ciocalteu method, while the antioxidant capacity of OVEO was assessed by DPPH (2,2-diphenyl-1-picrylhydrazyl) and FRAP (ferric reducing antioxidant power) methods. The cytotoxicity of OVEO (0.1–10 µg/mL) was assessed using the MTS assay. SW872 adipocytes were incubated with 0.4 mM PA for 24 h, with or without a 2 h preincubation of OVEO, and then stimulated with insulin (100 nM, 10 min) or a vehicle. Phosphorylation of Tyr-IRS-1, Ser-AKT, and Thr-AS160 was analyzed by Western blot, and glucose uptake was measured using 2-NBDG. Results: OVEO contained phenols and exhibits antioxidant capacity. All the concentrations of OVEO assessed were not cytotoxic on SW872 adipocytes. PA decreased basal phospho-AS160 as well as insulin-stimulated phospho-IRS1, phospho-AKT, phospho-AS160 and glucose uptake, while OVEO co-treatment enhanced these markers. Conclusions: These findings suggest a beneficial effect of OVEO on the PA-impaired insulin pathway and glucose uptake, which might be explained by its phenolic content and antioxidant capacity, highlighting its potential as a complementary therapeutic agent for IR and related metabolic disorders. Full article

Background/Objectives: Human immunodeficiency virus (HIV) has evolved from a fatal disease to a manageable chronic condition. However, stigma persists, affecting the lives and sexuality of HIV-positive people, particularly in the gay population. Research on their sexuality is limited, highlighting the need for studies that address their experiences and needs. The aim of the study is to explore the individuals’ experiences of sexuality in serodiscordant gay couples. Methods: A descriptive study was conducted using thematic content analysis. Data collection was carried out through in-depth interviews. Six gay men who have been and/or are in a serodiscordant relationship for at least one year participated in the research. Results: Five sub-themes were identified grouped into two main themes as follows: sexuality: a complex concept accentuated by HIV and the impact of serodiscordance on partners. Conclusions: It is essential to promote accurate information and health services tailored to the needs of people living with HIV while fostering gender equity and combating stigma related to HIV and the gay community. Experiencing sexuality in this context is not only possible but can be full and satisfying when adequate resources are available. Full article

Ravine forests are key to conserving biodiversity and maintaining ecosystem processes in fragmented landscapes. Here, we evaluated the phenology of plant species in the Los Nogales Nature Sanctuary (Lo Barnechea, Chile) using Sentinel-2 images (2019–2024) and the Alos Palsar DEM (12.5 m). We calculated the Normalized Difference Vegetation Index (NDVI), the Topographic Position Index (TPI), and Diurnal Anisotropic Heat (DAH) to assess vegetation dynamics across different topographic and thermal gradients. Generalized Additive Models (GAM) revealed that tree species exhibited more stable, regular seasonal NDVI trajectories, while shrubs showed moderate fluctuations, and herbaceous species displayed high interannual variability, likely reflecting sensitivity to climatic events. Spatial analysis indicated that trees predominated on steep slopes and higher elevations, herbs were concentrated in low-lying, moisture-retaining areas, and shrubs were more common in areas with higher thermal load. These findings highlight the significant role of terrain and temperature in shaping plant phenology and distribution, underscoring the utility of remote sensing and topographic indices for monitoring ecological processes in complex mountainous environments. Full article

Klebsiella pneumoniae carbapenemases (KPCs) are a group of class A β-lactamases of Gram-negative bacteria leading to difficult-to-treat infections. We evaluated the global epidemiology of KPC-producing Gram-negative clinical isolates. A systematic search of six databases (Cochrane Library, Embase, Google Scholar, PubMed, Scopus, and Web of Science) was conducted. Extracted data were tabulated and evaluated. After screening 1993 articles, 119 were included in the study. The included studies originated from Asia (n = 49), Europe (n = 29), North America (n = 14), South America (n = 11), and Africa (n = 3); 13 studies were multicontinental. The most commonly reported KPC-producing species were Klebsiella pneumoniae (96 studies) and Escherichia coli (52 studies), followed by Enterobacter cloacae (31), Citrobacter spp. (24), Klebsiella oxytoca (23), Serratia spp. (15), Enterobacter spp. (15), Acinetobacter baumannii complex (13), Providencia spp. (11), Morganella spp. (11), Klebsiella aerogenes (9), Pseudomonas aeruginosa (8), Raoultella spp. (8), Proteus spp. (8), and Enterobacter aerogenes (6). Among the studies with specific bla_KPC gene detection, 52/57 (91%) reported the isolation of bla_KPC-2 and 26/57 (46%) reported bla_KPC-3. The antimicrobial resistance of the studied KPC-producing isolates was the lowest for ceftazidime–avibactam (0–4%). Resistance to polymyxins, tigecycline, and trimethoprim–sulfamethoxazole in the evaluated studies was 4–80%, 0–73%, and 5.6–100%, respectively. Conclusions: The findings presented in this work indicate that KPC-producing Gram-negative bacteria have spread globally across all continents. Implementing proper infection control measures, antimicrobial stewardship programs, and enhanced surveillance is crucial. Full article

This study presents a quantitative electrophysiological method to directly measure the passive transport of ammonium ions through bacterial outer membrane porins. Using a zero-current reversal potential assay in planar lipid bilayers under defined bi-ionic gradients, this study evaluates the permeability of ammonium salts through two general diffusion porins: Omp-Pst2 from Providencia stuartii and OmpF from Escherichia coli. Under matched ionic conditions, Omp-Pst2 exhibited significantly higher ammonium flux—approximately 6000 ions per second per monomer at a 1 µM gradient—compared to ~4000 ions per second for OmpF. Importantly, the identity of the accompanying anion (chloride vs. sulfate) modulated both the ion selectivity and flux rate, highlighting the influence of counterion interactions on porin-mediated transport. These findings underscore how structural differences between porins—such as pore geometry and charge distribution—govern ion permeability. The method applied here provides a robust framework for quantifying nutrient flux at the single-channel level and offers novel insights into how Gram-negative bacteria may adapt their membrane transport mechanisms under nitrogen-limited conditions. This work not only enhances our understanding of outer membrane permeability to small ions like ammonium, but also has implications for antimicrobial strategy development and biotechnological applications in nitrogen assimilation. Full article

Background: Falls are a major public health concern among older adults, often resulting in injury, functional decline, and reduced quality of life. While handgrip strength (HGS), fall efficacy, and balance confidence have individually been associated with fall risk, their combined predictive value is still underexplored, particularly in physically active older adults. This study aimed to investigate the relationship between HGS, fall efficacy, and balance confidence and their association with fall risk in community-dwelling older adults engaged in regular exercise programs; A cross-sectional study was conducted with 280 participants aged 55 and over from community exercise programs near Lisbon, Portugal. Fall risk was assessed through self-reported falls in the past 12 months. HGS was measured with a dynamometer, fall efficacy using the Falls Efficacy Scale-International (FES-I), and balance confidence using the Activities-specific Balance Confidence (ABC) Scale. Statistical analyses included Spearman correlations and binary logistic regression. Results: Falls were reported by 26.4% of participants. Fall efficacy and balance confidence were significantly associated with fall history, while HGS was not. Fall efficacy was significantly associated with increased fall risk, as indicated by the odds ratio (OR = 3.37, p < 0.001), while balance confidence was negatively associated (OR = 0.95, p < 0.001). HGS was positively correlated with balance and confidence but not with fall incidence. Conclusions: Psychological factors, particularly fall efficacy and balance confidence, play a critical role in fall risk among physically active older adults. However, this study included physically active middle-aged and older adults living in the community, which should be considered when interpreting the generalizability of the results. These findings support the integration of simple, validated psychological assessments into fall prevention strategies in community settings. Full article

Antioxidant nanomaterials, particularly mesoporous silica nanoparticles (MSNs) functionalized with polyphenols, offer innovative solutions for protecting oxidation-sensitive components and enhancing bioavailability in pharmaceuticals or extending the shelf life of nutraceutical and food products. This study investigates the influence of MSNs functionalized with caffeic acid (MSN-CAF) on powder flow properties and their tableting performance. Aminated MSNs were synthesized via co-condensation and conjugated with caffeic acid using EDC/NHS chemistry. Antioxidant capacity was evaluated using DPPH^●, ABTS^●+, ORAC, and FRAP assays. Powder blends with varying MSN-CAF concentrations (10–70%) were characterized for flow properties (angle of repose, Hausner ratio, Carr’s index), tablets were produced via direct compression, and critical quality attributes (weight uniformity, hardness, friability, disintegration, nanoparticle release) were assessed. MSN-CAF exhibited reduced antioxidant capacity compared with free caffeic acid due to pore entrapment but retained significant activity. Formulation F1 (10% MSN-CAF) showed excellent flowability (angle of repose: 12°, Hausner ratio: 1.16, Carr’s index: 14%), enabling robust tablet production with rapid disintegration, low friability, and complete nanoparticle release in 10 min. Additionally, the antioxidant nanomaterial demonstrated biocompatibility with the HepG2 cell line. MSN-CAF is a versatile nanoexcipient for direct compression tablets, offering potential as an active packaging agent and delivery system in the nutraceutical and food industries. Full article

Background/Objectives: The male prepuce that covers the glans penis is richly innervated by low-threshold mechanoreceptors, which form cutaneous end-organ complexes (Meissner, Pacinian and Ruffini corpuscles) and mucous end-organ complexes (especially Krause-like corpuscles). The mechanosensory inputs from these formations are the beginning for spinal reflexes that regulate movements of intercourse and erection and, therefore, are required for sexual function. The study was aimed at analyzing the age-dependent changes in prepuce innervation. Methods: Here we used immunohistochemistry to investigate whether the innervation of the male prepuce undergoes age-dependent changes, analyzing subjects aged 4 months to 61 years. Results: Abundant Meissner corpuscles and Krause-like corpuscles were regularly found whose morphology, size, and topography were variable and were not correlated with age; however, Ruffini’s and Pacinian corpuscles were scarcely observed. The earliest evidence of Meissner corpuscles was observed at 4 months, and thereafter they undergo significant age-dependent variations in density. Until the age of 20 years increases progressively, remains stable until 40 years, and then the density decreases. Meissner’s corpuscle index paralleled that of density. Regarding Kause-like corpuscles already resemble the skin of 4-month-old subjects and from the age of 3 years they can be identified at all ages. Its density significantly increased until 10 years and then remained stable. Conclusions: Present results state that the mechanosensory innervation of the human foreskin reaches its maximum value around the age of 20, remains stable during adulthood and decreases with maturity. These findings contribute to a more complete understanding of foreskin innervation and add to the scientific knowledge base surrounding the potential harm of removing a richly innervated structure. Full article

The growing demand for sustainable materials has led to innovation in the development of natural compound-based solutions for industrial applications. This study introduces composite nanoparticles (NP-CsYBE) synthesized from chitosan (Cs) and saponin-rich yucca extract (YBE), highlighting their application in Pickering emulsions (PE). Characterization via DLS and AFM revealed NP-CsYBE as spherical particles with a hydrodynamic diameter of 230 nm and a ζ-potential of +36.9 mV, showing a non-aggregated morphology. Comparative analyses of emulsions formulated with Cs nanoparticles (Cs-NP) and YBE were conducted to assess the individual contributions of each component. Functional evaluations revealed that PE based on NP-CsYBE exhibited superior stability over time compared to those with Cs-NP or YBE alone. Additionally, the rheological properties of NP-CsYBE PE were influenced by pH: liquid-viscous behavior dominated at pH 4, while at pH 6.5, solid-elastic properties prevailed. Notably, increased temperature enhanced its mechanical properties. This innovative approach provides a framework for applying natural nanoparticles in PE formation, offering potential applications in the pharmaceutical, food, medical, and cosmetic industries, as well as biomaterials for protecting lipophilic substances. By leveraging natural resources, this work advances the understanding of natural nanoparticle-based systems and their role in developing sustainable and functional materials for industrial use. Full article

The occurrence of toxic metal(loid)s in surface freshwater is a global concern due to its impacts on human and ecosystem health. Conceptual and quantitative metal(loid) models are needed to assess the impact of metal(loid)s in watersheds affected by acid rock drainage. Few case studies have focused on arid and semiarid headwaters, with scarce hydrological and hydrochemical information. This work reports the use of WASP8 (US EPA) to model Al, Fe, As, Cu, and SO₄²⁻ concentrations in the Upper Elqui River watershed in north–central Chile. Calibrated model performance for total concentrations was “good” (25.9, RRMSE; 0.7, R²-d) to “very good” (0.8–0.9, R²-d). The dissolved concentrations ranged between “acceptable” (56.3, RRMSE), “good” (28.6, RRMSE; 0.7 d), and “very good” (0.9, R²-d). While the model validation achieved mainly “very good” (0.8–0.9, R²-d) predictions for total concentrations, the predicted dissolved concentrations were less accurate for all indicators. Sensitivity analysis showed that the partition coefficient is a sensitive constant for estimating dissolved concentrations, and that integrating sorption and sediment interaction reduces the model error. This work highlights the need for detailed and site-specific information on the reactive and hydrodynamic properties of suspended solids, which directly impact the partition coefficient, sedimentation, and resuspension velocity calibration. Full article

The optimal exploitation of genetic variability is essential for the success of breeding programs and for identifying quantitative trait loci (QTLs) in genetic association studies. These benefit from populations with a high number of individuals; however, they are expensive since extensive plant maintenance, characterization, and evaluation are required. Core collections offer a practical solution by reducing the number of individuals while representing the original diversity of the population. This study aimed to construct a core collection for Japanese plum to serve as pre-breeding material and enable genetic association studies for traits that are difficult to evaluate. Starting from a population of 1062 individuals genotyped by sequencing, genetic distance and allele coverage metrics were applied to construct several core collections. Genetic parameters and phenotype distribution comparisons allowed for the selection of a core collection of 108 individuals that maximized genetic variability while representative of the original population, confirmed by linkage disequilibrium and population structure analyses. Its usefulness was validated by successfully mapping flowering and maturity dates through marker–trait association. The core collection constructed here will help in the study of fruit quality traits and biotic and abiotic responses, ultimately generating molecular markers to assist the crop’s molecular breeding. Full article

Durvillaea incurvata, a Chilean brown seaweed, exhibits high antioxidant activity and polyphenol content, positioning it as a promising candidate for developing bioactive food ingredients. This study evaluated the anti-inflammatory activity of an ethanolic extract of Durvillaea incurvata, produced via ultrasound-assisted extraction, and its subsequent microencapsulation to obtain a functional food-grade ingredient. The extract’s anti-inflammatory capacity was assessed in vitro through hyaluronidase inhibition, and its cytotoxicity was evaluated using gastrointestinal cell models (HT-29 and Caco-2). Microencapsulation was performed by spray-drying with maltodextrin, and encapsulation efficiency (EE) was optimized using response surface methodology. Characterization included scanning electron microscopy, differential scanning calorimetry, and X-ray diffraction. The extract exhibited low cytotoxicity (cell viability > 75%). Optimal encapsulation conditions (inlet temperature: 198.28 °C, maltodextrin: 23.11 g/100 g) yielded an EE of 72.7% ± 1.2% and extract recovery (R) of 45.9% ± 2.4%. The microparticles (mean diameter, 2.75 µm) exhibited a uniform morphology, shell formation, glassy microstructure, and suitable physicochemical properties (moisture, 3.4 ± 0.1%; water activity, 0.193 ± 0.004; hygroscopicity, 30.3 ± 0.4 g/100 g) for food applications. These findings support the potential of microencapsulated Durvillaea incurvata extract as an anti-inflammatory ingredient for functional food development. Full article