Search Results (352)

The majority of studies of fungal utilization of chitosan are associated with the production of a specific enzyme, chitosanase, which catalyzes the hydrolytic cleavage of the macrochain. In our opinion, the development of approaches to obtaining materials with new functional properties based on non-destructive chitosan transformation by living organisms and their enzyme systems is promising. This study was conducted using a wide range of classical and modern methods of microbiology, biochemistry, and physical chemistry. The ability of the ascomycete Fusarium oxysporum Schltdl. to modify films of chitosan with average-viscosity molecular weights of 200, 450, and 530 kDa was discovered. F. oxysporum was shown to use chitosan as the sole source of carbon/energy and actively overgrew films without deformations and signs of integrity loss. Scanning electron microscopy (SEM) recorded an increase in the porosity of film substrates. An analysis of the FTIR spectra revealed the occurrence of oxidation processes and crosslinking of macrochains without breaking β-(1,4)-glycosidic bonds. After F. oxysporum growth, the resistance of the films to mechanical dispersion and the degree of ordering of the polymer structure increased, while their solubility in the acetate buffer with pH 4.4 and sorption capacity for Fe²⁺ and Cu²⁺ decreased. Elemental analysis revealed a decrease in the nitrogen content in chitosan, which may indicate its inclusion into the fungal metabolism. The film transformation was accompanied by the production of extracellular hydrolase (different from chitosanase) and peroxidase, as well as biosurfactants. The results obtained indicate a specific mechanism of aminopolysaccharide transformation by F. oxysporum. Although the biochemical mechanisms of action remain to be analyzed in detail, the results obtained create new ways of using fungi and show the potential for the use of Fusarium and/or its extracellular enzymes for the formation of chitosan-containing materials with the required range of functional properties and qualities for biotechnological applications. Full article

This study presents a scenario-based, two-dimensional flood modeling approach to assess the potential downstream impacts of a piping-induced dam failure triggered by seismic activity. The case study focuses on the Doğantepe Dam in northwestern Türkiye, located near an active branch of the North Anatolian Fault. Critical deformation zones were previously identified through PLAXIS 2D seismic analyses, which served as the physical basis for a dam break scenario. This scenario was modeled using the HEC-RAS 2D platform, incorporating high-resolution topographic data, reservoir capacity, and spatially varying Manning’s roughness coefficients. The simulation results show that the flood wave reaches downstream settlements within the first 30 min, with water depths exceeding 3.0 m in low-lying areas and flow velocities surpassing 6.0 m/s, reaching up to 7.0 m/s in narrow sections. Inundation extents and hydraulic parameters such as water depth and duration were spatially mapped to assess flood hazards. The study demonstrates that integrating physically based seismic deformation data with hydrodynamic modeling provides a realistic and applicable framework for evaluating flood risks and informing emergency response planning. Full article

Background/Objectives: This study aimed to determine whether the movement patterns and mental health of university teachers changed after returning to on-site class activities following the COVID-19 lockdown. Specifically, it compared levels of physical activity (PA), sedentary behavior time (SBT), active breaks (ABs), and symptoms of depression, anxiety, and stress among university teachers during online and on-site teaching periods. We also analyzed the association between movement patterns with psychological and anthropometric variables. Methods: University teachers who engaged in online teaching activities because of the COVID-19 restrictions and returned to on-site classes were included. Each teacher wore an accelerometer and answered the Depression Anxiety Stress Scales. The following parameters were assessed: SBT, light (LPA), moderate (MPA), and vigorous (VPA) (min/day); moderate–vigorous PA (MVPA) (min/week); steps/day and ABs/day. Results: Thirty-seven teachers with complete data from both phases were included. Once the on-site teaching activities resumed, LPA (9 min/day), MPA (6 min/day), total PA (20 min/day), MVPA (49 min/week), and steps/day (1100) significantly increased. While SBT showed no changes, ABs/day bouts increased. Depression and stress symptoms improved upon returning to on-site teaching activities. A positive association was identified between SBT and waist circumference (WC). There were negative associations between steps/day and MVPA with body mass index (BMI), steps/day with WC, and LPA with stress symptoms. Conclusions: Upon returning to on-site teaching activities, PA levels, steps/day, and ABs/day bouts all increased, although SBT remained elevated compared with during the lockdown. The teachers’ psychological symptoms improved. PA was associated with better health markers, while SBT was associated with increased WC. Full article

Promoting sustainable lifestyles through early interventions in schools is increasingly recognized as a critical component of public health and educational policy. Sustainable development, as outlined by the United Nations Sustainable Development Goals (SDGs), particularly Goal 3 (Good Health and Well-being) and Goal 4 (Quality Education), calls for integrating health-promoting behaviors into all aspects of life, including school settings. Active breaks (ABs) could represent a promising strategy to counteract these effects. This study assessed the impact of ABs on the attention of fifth-grade children, aiming to promote both immediate cognitive benefits and long-term health. A total of 32 primary children (age, 9.34 ± 0.77 years old), divided into an experimental group (AB sessions) and a control group, participated in this study. Attention and concentration were measured using the D2-R Test, while processing speed and distraction-related behaviors were tracked. Additionally, questionnaires assessed children’s and teachers’ perceptions. After five weeks, the experimental group demonstrated significant improvements in attention (p < 0.05), especially after high intensity ABs at 12:00. This study suggested the effectiveness of ABs as a tool for improving children’s attention and behavior in primary schools. The findings suggest that integrating physical activity breaks not only enhances cognitive function but also contributes to sustainable educational practices by fostering better learning environments and supporting children’s health and well-being. Full article

Seeds in soil are often exposed to cycles of hydration and dehydration, which can prime them by triggering physiological activation without leading to germination. While this phenomenon has been scarcely studied in wild species, it may play a critical role in enhancing drought resilience and maintaining seed viability under the warmer conditions predicted by climate change. In this study, I investigated the effects of hydration–dehydration cycles on germination response under water stress in eight Cistus species typical of Mediterranean shrublands. First, seeds were exposed to a heat shock to break physical dormancy, simulating fire conditions. Subsequently, they underwent one of two hydration–dehydration treatments (24 or 48 h) and were germinated under a range of water potentials (0, –0.2, –0.4, –0.6, and –0.8 MPa). Six out of eight species showed enhanced germination responses following hydration–dehydration treatments, including higher final germination percentages, earlier germination onset (T₀), or increased tolerance to water stress. These findings highlight the role of water availability as a key factor regulating germination in Cistus species and evidence a hydration memory mechanism that may contribute in different ways to post-fire regeneration in Mediterranean ecosystems. Full article

The hard-seed coat of Ormosia henryi significantly impedes germination efficiency in massive propagation, while conventional physical dormancy-breaking methods often result in compromised seed vigor, asynchronous seedling emergence, and diminished stress tolerance. Seed biopriming, an innovative technique involving the inoculation of beneficial microorganisms onto seed surfaces or into germination substrates, enhances germination kinetics and emergence uniformity through microbial metabolic functions and synergistic interactions with seed exudates. Notably, spermosphere-derived functional bacteria isolated from native spermosphere soil demonstrate superior colonization capacity and sustained bioactivity. This investigation employed selective inoculation of these indigenous functional strains to systematically analyze dynamic changes in endogenous phytohormones, enzymatic activities, and storage substances during critical germination phases, thereby elucidating the physiological mechanisms underlying biopriming-enhanced germination. The experimental results demonstrated significant improvements in germination parameters through biopriming. Inoculation with the Bacillus sp. strain achieved a peak germination rate (76.19%), representing a 16.19% increase over the control (p < 0.05). The biopriming treatment effectively improved the seed vigor, broke the impermeability of the seed coat, accelerated the germination speed, and positively regulated physiological indicators, especially amylase activity and the ratio of gibberellic acid to abscisic acid. This study establishes a theoretical framework for microbial chemotaxis and rhizocompetence in seed priming applications while providing an eco-technological solution for overcoming germination constraints in O. henryi cultivation. The optimized biopriming protocol addresses both low germination rates and post-germination growth limitations, providing technical support for the seedling cultivation of O. henryi. Full article

Background/Objective: The impact that lifestyle has on someone’s health has been widely proven. And the lifestyle can also be highly influenced by the sociodemographic background; however, there is less literature that focuses on this matter. Hence, the objective of the present study is to analyze the influence of sociodemographic variables on the lifestyle of the adult population. Methods: A cross-sectional multicenter study was conducted in 20 health centers of the Community of Madrid (Spain). A total of 365 participants were scheduled for nursing consultations and recruited through systematic probabilistic sampling. Lifestyle was assessed using the “Ponte a 100” questionnaire; based on the total score achieved by the participants, these were categorized into four groups depending on their need to adopt healthier lifestyle habits: minimal need (80–100 points), mild need (60–79 points), moderate need (40–59 points), and high need (<39 points). Results: Values ranged from 23 to 98 points in the Lifestyle Index (ISEV), with an average of 71.8 (SD = 14.6 points). Older individuals had better eating habits (β = −1.982), while younger individuals had better physical activity habits and a higher consumption of toxic substances. Men consumed more alcohol (β = −2.307) and felt happier with their lives, while women took more active breaks. Being a student was associated with higher levels of stress and anxiety, lower physical activity and leisure time, and higher alcohol consumption. Retirees had better emotional well-being indices (β = 0.999). Lower income levels were associated with occasional drug use and poorer emotional well-being. People with university degrees had better emotional states (β = 0.861) and better eating habits (β = 1.652) and engaged in more intense physical activity. Having no chronic diseases was related to being more physically active (β = 1.789). Conclusions: The study population generally presents a healthy lifestyle. The dimension of emotional well-being was the most influenced by sociodemographic factors. This study contributes to understanding the impact of socioeconomic variables on lifestyle. Full article

Background: The development of motor competencies in childhood can enhance the trajectory of physical activity throughout life. However, few studies have examined the effects of physical activity programs on motor competencies in schoolchildren with special educational needs. Aim: Our aim was to analyze the effects of a video-guided active break program on motor competencies in schoolchildren aged 6 to 10 years with special educational needs. Methods: A prespecified subanalysis of a multicenter randomized controlled trial was conducted with a sample of 161 schoolchildren (7.8 ± 1.1 years, 32% girls) with special educational needs from five public schools in Chile. Participants were assigned to a control group (CG, n = 85) with no active breaks or an experimental group (EG, n = 76) with active breaks. A 12-week video-guided active break program was implemented in the classroom twice daily, five days per week. The intervention was delivered via a web-based platform. Basic motor competencies were assessed using the MOBAK 1–2 and MOBAK 3–4 tests. Results: A significant time × group interaction was found for object control, F(1154) = 11.365, p < 0.001, η²_p = 0.011; jumping, F(1154) = 11.047, p = 0.001, η²_p = 0.067; and running, F(1154) = 4.881, p = 0.029, η²_p = 0.031. These results indicate that the experimental group showed significantly greater improvements in object control, jumping, and running abilities compared to the control group. Conclusions: The active break program significantly improved motor skills in schoolchildren with special educational needs. The program proved to be both feasible and effective in enhancing students’ motor competencies. School-based guided active break programs may play a role in promoting motor competencies among schoolchildren with special educational needs. Clinical Trial ID NCT06423404 Full article

The remaining lifetime of the cable insulation is an important but hard topic for the industry and research groups as there are more and more cables nearing their designed life in China. However, it is hard to accurately and efficiently obtain the ageing characteristic parameters of cross-linked polyethylene (XLPE) cable insulation. This study systematically analyzes the evolution of the remaining insulation lifetime of XLPE cables under different ageing states using the step-stress method combined with the inverse power model (IPM) and a physical-driven model (Crine model). By comparing un-aged and accelerated-aged specimens, the step-stress breakdown tests were conducted to obtain the Weibull distribution characteristics of breakdown voltage and breakdown time. Experimental results demonstrate that the characteristic breakdown field strength and remaining lifetime of the specimens decrease significantly with prolonged ageing. The ageing parameter of the IPM was calculated. It is found that the ageing parameter of IPM increases with the ageing time. However, it can hardly link to the other properties or physic parameters of the material. The activation energy and electron acceleration distance of the Crine model were also calculated. It is found that ageing activation energy stays almost the same in samples with different ageing time, showing that it is a material intrinsic parameter that will not change with the ageing; the electron acceleration distance increases with the ageing time, it makes sense that the ageing process may break the molecule chain of XLPE and increase the size of the free volume. It shows that the Crine model can better fit the physic process of ageing in theory and mathematic, and the acceleration distance of the Crine model is a physical driven parameter that can greatly reflect the ageing degree of the cable insulation and be used as an indicator of the ageing states. Full article

The multiscale coupling characteristics of the kinematic interface behavior of mechanical transmission systems are the core factors affecting system accuracy and lifetime. In this paper, we propose an innovative framework to achieve multiscale modeling from surface topographic parameters to system-level dynamics response through four stages: microscopic topographic regulation, mesoscopic wear modeling, macroscopic gap evolution, and system vibration prediction. Through the active design of laser-textured surfaces and gradient coatings, the contact stress distribution can be regulated to keep the wear extension; combined with the multiscale physical model and joint simulation technology, the dynamic feedback mechanism of wear–gap–vibration is revealed. Aiming at the challenges of data scarcity and mechanism complexity, we integrate data enhancement and migration learning techniques to construct a hybrid mechanism–data-driven life prediction model. This paper breaks through the limitations of traditional isolated analysis and provides theoretical support for the design optimization and intelligent operation and maintenance of high-precision transmission systems. Full article

Development of bio-based active packaging systems for lipid stabilization presents critical importance in preserving lipid integrity and ensuring food safety. Zein/citric acid (Z/CA) composite films containing grape seed ethanol extract (GSEE) (0–8% w/w) were prepared by the solvent casting method. The structural, functional, and environmental properties of the films, including physical and chemical properties, mechanical properties, antioxidant capacity, antibacterial activity, oxidation inhibition effect, and biodegradability, were comprehensively characterized and evaluated. Progressive GSEE enrichment significantly enhanced film thickness (p < 0.05), hydrophobicity, and total phenolic content, while increasing water vapor permeability by 61.29%. Antioxidant capacity demonstrated radical scavenging enhancements of 83.75% (DPPH) and 89.33% (ABTS) at maximal GSEE loading compared to control films. Mechanical parameters exhibited inverse proportionality to GSEE concentration, with tensile strength and elongation at break decreasing by 28.13% and 59.43%, respectively. SEM microstructural analysis revealed concentration-dependent increases in surface asperity and cross-sectional phase heterogeneity. Antimicrobial assays demonstrated selective bacteriostatic effects against Gram-negative pathogens. Notably, the composite film containing 6 wt% GSEE had a remarkable restraining effect on the oxidation of lard. The soil degradation experiment has confirmed that the Z/CA/GSEE composite film can achieve obvious degradation within 28 days. The above results indicate that the Z/CA/GSEE composite material emerges as a promising candidate for sustainable active food packaging applications. Full article

With the growing awareness of public health, urban parks have increasingly become popular venues for physical activities due to their accessibility and pleasant landscapes, among which walking, jogging, and running dominate. This study innovatively integrates exercise trajectory data from the Strava platform and semantic segmentation technology to analyze the interaction mechanisms among park view elements, physical activities, and physiological responses, based on empirical data from three representative parks in Shanghai. This study includes the following: (1) acquiring hotspot exercise paths and physiological data (heart rate and speed) of walking, jogging, and running users through the open Strava platform; (2) conducting semantic segmentation on real-word photos of three case parks to extract 17 types of park elements; (3) applying Spearman’s correlation analysis to reveal the differential impacts of park elements on physiological responses under walking, jogging, and running behaviors, demonstrating that combinations of elements such as trees, water bodies, fences, and sky influence exercise performance; and (4) constructing scene modules for site attraction, training improvement, and restorative relaxation for walking, jogging, and running, and proposing phased landscape scene sequence strategies to provide quantitative guidance for health-oriented park planning and design. This study breaks through the limitations of traditional subjective evaluations by coupling objective physiological data with spatial elements, offering novel insights for optimizing the exercise functionality of urban green spaces. Full article

Random lasers (RLs) based on glasses and glass-ceramics doped with rare-earth ions (REI) deserve great attention because of their specific physical properties such as large thermal stability, possibility to operate at high intensities, optical wavelength tunability, and prospects to operate Fiber-RLs, among other characteristics of interest for photonic applications. In this article, we present a brief review of experiments with RLs based on tellurite and germanate glasses and glass-ceramics doped with neodymium (Nd³⁺), erbium (Er³⁺), and ytterbium (Yb³⁺) ions. The glass samples were fabricated using the melt-quenching technique followed by controlled crystallization to achieve the glass-ceramics. Afterwards, the samples were crushed to obtain the powder samples for the RLs experiments. The experiments demonstrated RLs emissions at various wavelengths, with feedback mechanisms due to light scattering at grain/air and crystalline/glass interfaces. The phenomenon of replica symmetry breaking was verified through statistical analysis of the RLs intensity fluctuations, indicating a photonic phase-transition (corresponding to the RL threshold) analogous to the paramagnetic-to-spin glass transition in magnetic materials. The various results reported here highlight the potential of glasses and glass-ceramics for the development of RLs with improved performance in terms of reduction of laser threshold and large lifetime of the active media in comparison with organic materials. Full article

Fatigability, a phenotype of poor energy regulation, is associated with lower physical activity in older adults, but independent associations with sedentary behavior are unknown. We examined whether sedentary behavior was associated with fatigability using cross-sectional data from the Study of Muscle, Mobility and Aging. Mean sedentary time, sedentary bout length, and sedentary breaks/day were measured using 7-day waking hour data collected from a thigh-worn accelerometer. Fatigability was assessed using the Pittsburgh Fatigability Scale Physical subscale (PFS, score 0–50, higher = greater fatigability) and the Pittsburgh Performance Fatigability Index (PPFI), a percentage decline of observed cadence to maximal cadence from a wrist-worn accelerometer captured during a usual-paced 400 m walk (range 0–100%, higher = more performance deterioration). The participants (N = 663; 76.4 ± 5.1 years, 58% women, 54% high PFS, median PPFI 1.4%) were sedentary for 614.8 ± 111.7 min/day, with a mean 15.0 ± 5.5 min/day bout length and mean 46.1 ± 13.2 sedentary breaks/day. Higher total sedentary time was associated with greater PFS Physical score (β = 0.71, p = 0.0368), but this association was not independent of step count/day. After adjusting for step count/day, higher sedentary time was associated with lower PPFI score (β = −0.44, p = 0.0039). Sedentary bout length and breaks/day were not associated with perceived or performance fatigability. Future studies should aim to better understand the inter-relatedness of these behaviors. Full article

Microalgae are a sustainable source of bioactive compounds and nutrients that do not compete with crops for arable land. Lobosphaera sp. was used to produce biodegradable films. Bioactive compounds, polysaccharides, and proteins were extracted from this microalga. The total phenolic content (TPC) and antioxidant activity (ABTS, DPPH, and ORAC) of the bioactive-rich extract were determined, and its composition was analyzed for phenolics using LC-ESI-QqTOF-HRMS and for lipids using GC-FID. The cytotoxicity of this extract on Caco-2 cells was also assessed. Different types of films were produced based on alginate (2%) (film A) and alginate with polysaccharides-rich (PS-rich) extract (0.5%) (film B); PS-rich extract and bioactive-rich extract (0.25%) (film C); protein-rich (P-rich) extract (0.5%) (film D); and P-rich extract and bioactive-rich extract (film E). The antioxidant activity and physical parameters of the films, such as thickness, color, water vapor permeability, solubility, tensile strength (TS), and elongation at break (EAB), were determined. The TPC of the bioactive-rich extract was 1.07 ± 0.05 mg GAE/100 mg DW, and its antioxidant activity was 2.44 ± 0.27, 1.67 ± 0.15, and 11.90 ± 1.22 µmol TE/100 mg DW for ABTS, DPPH, and ORAC, respectively. The extract showed no cytotoxicity to gut cells at concentrations equal to or below 1.0 mg/mL. Film E obtained the best results for the antioxidant activity, 451.06 ± 14.68 and 212.81 ± 39.12 µM TE/mg film for ABTS and DPPH, respectively. In addition, the films enriched with the bioactive-rich extract (films C and E) presented antimicrobial activity against Listeria monocytogenes. These films controlled the mold and yeast growth in strawberries during a four-day storage at 25 °C. All films were completely soluble in water and hydroethanolic solutions but only partially solubilized in acetic acid (3%). TS and EAB were not significantly different among the films. It was possible to produce biodegradable films using microalga Lobosphaera sp. with good bioactivity and physical characteristics. Full article