Search Results (2,437)

An important area of health is health promotion. A healthy lifestyle supports health improvement and early prevention of chronic diseases. Stimulation of the body by cold water swimming and swimming in a swimming pool can lead to adaptive changes beneficial for the human cardiovascular system. Within the winter swimming season of 2023/2024, for a period of 5 months, from November to March, once a week, study participants (n = 30; n = 15 females and n = 15 males) from the Krakow Society of Winter Swimmers ‘Kaloryfer’ in Krakow (Poland) practiced winter swimming in cold water (4–5 °C) and swam in the sports pool of the University of Physical Culture in Krakow in water at a temperature of 28 °C. After a full season of winter swimming and swimming pool sessions, both males and females exhibited a tendency towards lower erythrocyte (p = 0.002), leukocyte (p < 0.001), and platelet counts (p < 0.001), as well as an increase in blood plasma viscosity (within normal limits) (p = 0.001), without any changes in blood aggregation or fibrinogen indicators. The remaining morphological indicators and the elongation index demonstrated only limited variation. Winter swimming induces positive changes in blood morphology and rheology. Full article

A flagellar motor can rotate either counterclockwise (CCW) or clockwise (CW), and rotational switching is triggered by conformational changes in FliG, although the molecular mechanism is still unknown. Here, we found that cheY deletion, which locks motor rotation in the CCW direction, restored the motility abolished by the fliG L259Q mutation. We found that the CCW-biased fliG G214S mutation also restored the swimming of the L259Q mutant, but the CW-biased fliG G215A mutation did not. Since the L259 residue participates in forming the FliG hydrophobic core at its C-terminal domain, mutations were introduced into residues structurally closer to L259, and their motility was examined. Two mutants, D251R and L329Q, exhibited CW-biased rotation. Our results suggest that mutations in the hydrophobic core of FliG_C collapse its conformational switching and/or stator interaction; however, the CCW state of the rotor enables rotation even with this disruption. Full article

In this work, the hypolipidemic and antioxidative capacity of FSGLR (S7) and GIEWA (S10) from miiuy croaker swim bladders was explored systematically in an oleic acid (OA)-induced nonalcoholic fatty liver disease (NAFLD) model of HepG2 cells. Moreover, the hypolipidemic activity of S7 and S10 and their antioxidative abilities were preliminarily investigated in combination with molecular docking technology. The results indicated that S7 and S10 could decrease the amount of lipid accumulation and the content of triglycerides (TG) and total cholesterol (TC) in the OA-induced NAFLD cell model in a dose-dependent manner. In addition, S7 and S10 exhibited better bile salt binding, pancreatic lipase (PL) inhibition, and cholesterol esterase (CE) inhibition capacities. The hypolipidemic mechanisms of S7 and S10 were connected with the downregulation of the mRNA expression levels of adipogenic factors, including sterol-regulatory element-binding protein-1c (SREBP-1c), acetyl-CoA carboxylase (ACC), sterol-regulatory element-binding protein (SREBP)-2, hydroxymethylglutaryl-CoA reductase (HMGR), and fatty acid synthase (FAS) (p < 0.01), and the upregulation of the mRNA expression of β-oxidation-related factors, including carnitine palmitoyltransferase 1 (CPT-1), acyl-CoA oxidase 1 (ACOX-1), and peroxisome proliferator-activated receptor α (PPARα). Moreover, FSGLR (S7) and GIEWA (S10) could significantly protect HepG2 cells against OA-induced oxidative damage, and their antioxidant mechanisms were related to the increased activity of intracellular antioxidant proteases (superoxide dismutase, SOD; glutathione peroxidase, GSH-PX; catalase, CAT) to remove excess reactive oxygen species (ROS) and decrease the production of malondialdehyde (MDA). The presented findings indicate that the hypolipidemic and antioxidant functions and mechanisms of S7 and S10 could make them potential hypolipidemic and antioxidant candidates for the treatment of NAFLD. Full article

Emerging evidence from observational studies suggests that lifestyle modifications, particularly moderate-intensity exercise, may confer neuroprotective benefits against dementia, potentially by enhancing brain resistance through clearance mechanisms. Using light-sheet fluorescence microscopy (LSFM) with tissue clearing, we investigated the role of voluntary swimming in ameliorating β-amyloid pathology in a transgenic Alzheimer’s disease (AD) mouse model. Twenty 52-week-old hAPPsw mice were randomly divided into a 5-week voluntary swimming intervention group and a control group (each n = 10). Each session included a 10-min swim followed by a 10-min rest, escalating from one session per day in the first week to three sessions per day by the fifth week. The excised brains were prepared using tissue-clearing and volume immunostaining with thioflavin-S for β-amyloid. For LSFM imaging, the individual plaque area and volume, total plaque load, and morphological parameters were quantified via an Imaris-based three-dimensional (3D) volumetric surface model. Visual comparison revealed that the intervention group presented significantly lower β-amyloid accumulation. The total surface volume of β-amyloid accumulation in the intervention group was significantly lower than that of the control group (intervention, 122,180,948 μm³ [105,854,660–169,063,081]; control, 167,201,016 μm³ [139,367,765–193,535,450]; p = 0.043). There were no significant differences in the morphological parameters, such as ellipticity and sphericity. Our LSFM study demonstrated notable reductions in β-amyloid, as evidenced by a decrease in total surface volume, in 52-week-old transgenic mice after a 5-week structured swimming program, supporting the notion that even in advanced AD stages, leisure-time voluntary swimming serves as an efficacious intervention for augmenting resistance to pathology. Full article

Different pollutants often coexist in natural environments, making it crucial to monitor and study the ecotoxicological effects of composite pollutants in aquatic environments. Nanoplastics and heavy metals are emerging environmental pollutants that can affect the health of aquatic organisms and threaten human health via the food chain. In this study, zebrafish was employed as a model organism to explore the effects of short-term exposure to polystyrene nanoplastics (PS-NPs) and heavy metal copper ions (Cu²⁺) either individually or in combination on fish behavior. First, the single and combined toxicity of Cu²⁺ and PS-NPs to adult zebrafish was investigated to obtain the LC₅₀ values of the two pollutants at 24, 48, 72, and 96 h. Then, the effects of sub-lethal concentrations of Cu²⁺ (0.06, 0.15, and 0.3 mg/L), PS-NPs (5, 10, and 15 mg/L) and binary mixtures containing Cu²⁺ and PS-NPs (0.06 mg/L + 10 mg/L, 0.15 mg/L + 10 mg/L, and 0.3 mg/L + 10 mg/L) on the swim speed and individual distance of zebrafish within 4 h were studied. The results show that the LC₅₀ value for single exposure of zebrafish to Cu²⁺ decreased with the increase in the exposure time, while PS-NPs showed no significant acute toxicity to zebrafish when the concentration was less than 20 mg/L and the exposure time was less than 96 h. The combined exposure of zebrafish to Cu²⁺ and PS-NPs resulted in a 3.1–32.2% reduction in the LC₅₀ value at different time points compared with Cu²⁺ alone. In the behavioral study, both single and combined exposure to Cu²⁺ and PS-NPs induced hyperactivity and aggregation phenomena in the zebrafish at different levels; the duration of these two phenomena was correlated with the concentration of the pollutants. The combined exposure to Cu²⁺ and PS-NPs exacerbated the behavioral changes in zebrafish compared with exposure to Cu²⁺ alone, reducing their hyperactivity time, average swim speed and aggregation time by 30.7–41.0%, 13.6–15.4%, and 28.3–28.8%, respectively. Therefore, this study indicates that the combined short-term exposure to PS-NPs and Cu²⁺ can exacerbate the toxicity of pollutants, and also proves the feasibility for early warning of combined NPs and heavy metals pollution based on adult zebrafish behavioral indicators. Full article

Vitamin E (VitE), a potent antioxidant, has demonstrated significant potential in mitigating oxidative stress and cellular damage, making it a valuable agent for countering environmental toxicities, including those caused by polystyrene nanoplastics (PSNPs). This study examined the effects of PSNPs on the zebrafish visual system and evaluated the protective role of VitE. Zebrafish embryos were exposed to PSNPs (0.01, 0.1, 1, and 10 μg/mL) with or without 20 μM VitE co-treatment from fertilization to 6 days post-fertilization (dpf). Visual function, morphology, and molecular responses were assessed at 4 or 6 dpf. Exposure to PSNPs at concentrations of 0.1 to 10 μg/mL significantly increased bioaccumulation in the zebrafish eye in a concentration-dependent manner and disrupted the visual system. These disruptions caused a reduction in the eye-to-body length ratio and decreased optomotor response positivity and swimming distance, indicating impaired visual function and behavior. Furthermore, PSNPs elevated reactive oxygen species (ROS) levels, induced retinal apoptosis, and disrupted gene expression related to visual development (six6, pax2, pax6a, and pax6b), apoptosis (tp53, casp3, bax, and bcl2a), and antioxidant defense (sod1, cat, and gpx1a). VitE co-treatment significantly mitigated these adverse effects, reducing oxidative damage, restoring antioxidant defenses, and preserving retinal function. This study highlights the potential of VitE as a protective agent against PSNP-induced visual dysfunction and underlines the urgent need to address nanoplastic pollution to protect aquatic ecosystems. Full article

Progestogens’ anti-anxiety and anti-depressive effects and mechanisms are not well-understood. Progestogens are hypothesized to have anti-anxiety and anti-depressive effects on behavior, independent of actions at nuclear progestin receptors (NPRs) and dependent on allopregnanolone (5α-pregnan-3α-ol-20-one; 3α,5α-THP), a 5α-reduced, neuroactive metabolite of progesterone (P₄). Adult c57 mice in behavioral estrus (proestrus; pro) showed more anti-anxiety-like and anti-depressant-like behavior and higher levels of estradiol (E₂), P₄, and allopregnanolone in the hippocampus/amygdala complex. Proestrus c57 > 5α-reductase knockout (5αRKO) mice made more central entries in an open field than diestrus c57 and 5αRKO mice that were not different. Ovariectomized (OVX) c57 mice administered 1, 2, or 4 mg/kg P₄ SC showed dosage-dependent increases in central entries in an open field (more anti-anxiety-like behavior); 5αRKO mice had maximal increases at 1–2 mg/kg P₄. OVX c57 and 5αRKO mice showed maximum increases in central entries with SC 3α,5α-THP (4 mg/kg), and c57s showed a similar maximal response to P₄ (4 mg/kg), but 5αRKOs response was half at that dosage. P₄ (4 mg/kg SC to OVX c57 or progestin receptor knockout (PRKO) mice decreased immobility (depression-like behavior) in the forced swim task. Effects of E₂ and veh were similar in both groups. Levels of 3α,5α-THP in the hippocampus/amygdala were consistent with effects on central entries in the open field. Levels of brain-derived neurotrophic factor (BDNF) in the hippocampus/amygdala were greater among E₂-primed (0.09 mg/kg, SC) vs vehicle-administered mice. In sum, adult female mice can be responsive to P₄ for anti-anxiety/anti-depressant-like behavior; such effects may be independent of NPRs but require 5α-reduction and E₂’s priming actions at BDNF in the hippocampus/amygdala complex. Full article

In this study, we investigate whether differences in sociodemographic and housing characteristics may lead to heterogenous reactions on water demand across households in the event of an unexpected shock. In this sense, we estimate a switching regression model for residential water usage in Gijón, Spain, between 2017 and 2021, exploiting the exogenous impact of the COVID-19 pandemic and various movement restriction phases. A rich dataset that integrates real data on water consumption and pricing, alongside reported household and housing characteristics, allows us to effectively control the heterogeneity of water consumers and test changes in marginal effects over time. Our findings reveal a significant increase in average water consumption coinciding with the onset of the pandemic. This increase in water usage was particularly pronounced among households with more members and those residing in older houses that also owned outdoor amenities such as gardens or swimming pools, among other socioeconomic and housing characteristics. Additionally, our study indicates that the price elasticity of water demand did not significantly differ from zero during the periods of the State of Alarm and the New Normal. This suggests that the implementation of movement restrictions and teleworking may have amplified households’ preferences and dependence on water, thus fostering increased water consumption. Furthermore, our results point towards unchanged residential information or knowledge of the expense of water services despite the time spent at home. Full article

As an electrically driven artificial muscle, dielectric elastomer actuators (DEAs) are notable for their large deformation, fast response speed, and high energy density, showing significant potential in soft robots. The paper discusses the working principles of DEAs, focusing on their reversible deformation under electric fields and performance optimization through material and structural innovations. Key applications include soft grippers, locomotion robots (e.g., multilegged, crawling, swimming, and jumping/flying), humanoid robots, and wearable devices. The challenges associated with DEAs are also examined, including the actuation properties of DE material, material fatigue, viscoelastic effects, and environmental adaptability. Finally, modeling and control strategies to enhance DEA performance are introduced, with a perspective on future technological advancements in the field. Full article

Monitoring physiological parameters is vital for tracking swimmers’ progress and performance. This study examines an elite male swimmer’s nutrition during his preparation for the 2024 Paris Olympics, considering his metabolic rate and body composition. His resting energy needs (2905 ± 407.99 kcal/day) were measured using indirect Cosmed K5, calorimetry, and body composition determined through skinfold measurements. Nutrition plans were developed using software, varying with his training intensity—providing 2910 ± 379 kcal/day on rest days, and 4238 ± 562 kcal/day on intense days. The analysis of the correlations between key variables revealed strong and diverse interactions among anthropometric, metabolic data, and energy substrates. Thus, weight exhibited a very strong positive correlation with lean mass (FFM), indicating that higher weight is associated with increased lean mass. Conversely, the moderate correlation between weight and body fat percentage suggests a weaker association. The amount of skin folds accurately reflects the body fat percentage. Ensuring that a high-energy dietary intake aligned with his actual needs throughout the season was crucial for sustaining performance. Experimenting with fueling and recovery tactics during smaller competitions enabled the athlete to meet energy and nutrient demands at the elite level. Full article

In 2019, a disease outbreak struck a hybrid sturgeon farm (Huso dauricus ♀ × A. schrenckii ♂) in Tiantai, Zhejiang province, leading to the deaths of 8000 sturgeons. The sturgeons exhibited reduced appetite, lethargic and uncoordinated swimming, and physical signs such as reddish petechiae and ulcers on the body and fins. Hemorrhagic spots were observed on the kidneys, spleen, and gonads, alongside reddish intestines with hemorrhagic ascites in the abdominal cavity. ST-1902 was isolated and identified as Aeromonas hydrophila through physiological and biochemical characterization and 16S rDNA sequence analysis. The pathogenicity of ST-1902 was confirmed through a challenge test, with a median lethal dosage (LD50) of 7.9 × 10⁶ CFU/IND. Histopathological examination showed hyperplasia and neoplasm-like changes in the epicedial mesothelial tissues, enlarged and necrosis renal tissue, and serious hemosiderosis in spleen and gills. Virulent genes (Aer, Epa, Alt, Hly, and Act) were detected in ST-1902, corresponding to typical β-hemolysis, extracellular protease, and enterotoxin. Moreover, antimicrobial experiment detection indicated ST-1902 is sensitive to quinolones and phenicols but resistant to sulfamethoxazole, aminoglycoside antibiotics with Sul1, and Intl and Ant (3”)-I. These results suggest that A. hydrophila was the causative agent of the sturgeon disease and highlight the emerging threat it poses to the sturgeon industry. Full article

The Ylistrum japonicum is a scallop of commercial significance, renowned for its capacity to undertake long-distance swimming. A total of 150 individuals were collected to explore the connections between morphological traits and quality traits and to determine the nutritional components of the adductor muscle. The results showed a robust positive correlation between morphological traits and quality traits, with certain variations in the intensity of the correlation depending on gender. For both female and male individuals, the most significant factor directly influencing the quality traits was shell width, and shell length had the greatest indirect influence on the individual quality traits. The nutritional results of the adductor muscle of Y. japonicum showed that the moisture content was 80.17%, the ash content was 1.43%, the protein content was 16.93%, the fat content was 0.67%, and the carbohydrate content was 0.80%. Furthermore, a total of 17 amino acids and a total of 23 fatty acids were detected. The study’s findings contribute to the understanding of the quality traits and nutritional value of Y. japonicum, laying a basis for the development of selective breeding strategies aimed at boosting the species’ aquaculture potential. Full article

This paper reviews the numerical simulation method for thermal anti-icing. Typically, the numerical study of an anti-icing system involves a coupled simulation of various physical processes: airflow, droplet flow, thin water film flow on the wall, and heat conduction within the solid wall. Airflow is commonly simulated using the Reynolds-Averaged Navier–Stokes method, while droplet flow can be modeled using either the Eulerian or Lagrangian approach. For simulating water film flow, there are three primary models: the Messinger model, the SWIM model, and the Myers model. The heat transfer process within the solid wall can be coupled with the external air/droplet and film flow using either a tight-coupling or a loose-coupling method. When simulating an electrothermal anti-icing system, methods such as the equivalent heat conductivity scheme or shell conduction method are employed to handle heat conduction in multi-layer thin walls. To improve the accuracy of thermal anti-icing simulations, additional research is still necessary, focusing on studies on rivulet flow, bead flow, and the heat convection coefficient on the system’s wall. Full article

Background: The main aim of this study was to identify the differences between subgroups of swimmers based on physiological (peak oxygen uptake—VO₂peak), strength (average tethered swimming force—60F_ave), stroke kinematics (v₁₀₀—swimming speed at 100 m front crawl, stroke rate—SR, stroke length—SL), and anthropometrical (i.e.,: biological age—BA, body height—BH, body mass—BM) factors within swimmers at different levels of maturity (BA). Methods: This study involved 39 female swimmers (age: 12.88 ± 0.54 years, BA: 13.98 ± 1.91 years). Cluster analysis (k-cluster) and stepwise multiple regression was performed. Results: Significant correlations were observed between v₁₀₀ and BA, 60F_ave, AS, VO₂peak. Stepwise multiple regression indicated 60F_ave and VO₂peak as the main explanatory variables of v₁₀₀ (R² = 0.60, p < 0.0001). Cluster analysis allowed us to distinguish three groups of swimmers, differing in BA (cluster 1: 14.07 ± 0.96 years, cluster 2: 17.05 ± 1.53, cluster 3: 11.94 ± 0.95) and v₁₀₀, as well as in BH, FFM, AS. Conclusions: There were differences between cluster groups, with early mature swimmers characterized by the highest BH, FFM, AS, 60F_ave, and VO₂peak. Probably, biologically younger late mature swimmers (cluster 3) are slower than the other 2 groups (cluster 1 and 2) because of being less somatically developed. Based on these study results, coaches should ensure further development of aerobic and anaerobic conditioning among normal mature swimmers with simultaneous focus on improving technique skills among early mature ones. Full article

The objective of this study was to assess the antidepressant efficacy of a novel imipramine–magnesium (IMI–Mg) complex in comparison to the administration of imipramine and magnesium individually. The study utilized adult male albino Swiss mice. Behavioral assessments were conducted using the forced swim test (FST) and the tail suspension test (TST). A locomotor activity test was conducted to exclude false positive results in the FST and TST. Moreover, the study assessed oxidative stress levels in the mice subjected to acute environmental stress by measuring glutathione peroxidase, glutathione reductase, total oxidant status, and total antioxidant status. The administration of the IMI–Mg complex at doses of 5, 10, and 20 mg/kg resulted in a reduction in immobility time in both behavioral tests, thereby indicating the antidepressant-like potential of the tested complex, which was similar to the one observed after the administration of these two compounds as separate drug forms. The efficacy of the novel IMI–Mg complex represents a significant advancement and provides a foundation for future research. This innovative agent has the potential to enhance the safety profile of the therapy, streamline the treatment protocol, improve patient satisfaction, and promote adherence to the therapeutic regimen. Full article