Search Results (1,034)

Basketball performance is influenced by cardiorespiratory fitness and body composition. However, evidence regarding the ability of maximal oxygen uptake (VO₂max) to distinguish between competitive levels remains inconsistent. This study aimed to examine differences in cardiorespiratory fitness and body composition between professional and amateur basketball players and to explore their contribution to variability in relative VO₂max. This pilot study also informed sample size estimation for future studies. A cross-sectional study was conducted with 12 professional (21.0 ± 2.3 years; BMI: 25.37 ± 3.04 kg/m²) and 12 amateur (22.6 ± 1.7 years; BMI: 26.83 ± 3.24 kg/m²) male basketball players. Absolute and relative VO₂max, ventilatory thresholds, and body composition (five-component fractionation) were assessed. Between-group comparisons were performed using Welch’s t-tests, effect sizes were estimated using Hedges’ g, and covariance analyses were adjusted for height and body fat percentage. No statistically significant differences were observed in relative VO₂max between groups. However, the absolute second ventilatory threshold was significantly higher in professional players, and absolute VO₂max showed a large effect size favoring this group. Professionals also showed lower body fat percentage and greater fat-free mass (p < 0.01; g ≈ 1.2). These findings suggest that body composition differences may partly explain variability in relative VO₂max between competitive levels. Full article

Background: Adequate muscle perfusion, particularly at the level of muscle microcirculation (MM), is essential for muscle function, recovery, and tissue health. Percussive therapy (PT) is increasingly used to support recovery and injury prevention and has shown consistent benefits for range of motion and perceived recovery. However, the underlying physiological mechanisms remain insufficiently understood, and evidence regarding its effects on MM is limited. This study investigated the acute effect of a single PT session on MM and muscle oxygen saturation (SmO₂). Methods: Twenty-two healthy volunteers (24.2 ± 3.0 years) underwent a single PT application (two or four minutes) to the thigh using a handheld percussive device. MM, SmO₂, and the perceived somatosensory sensation (PSS) were assessed at baseline and at five-minute intervals up to 40 min post-application. Data were analyzed using linear mixed models adjusted for age, lower-body fat percentage, and intervention duration. Results: A significant main effect of time was found for both MM and SmO₂. MM increased significantly compared to baseline from 5 to 15 min post-application (all p < 0.001), while SmO₂ increased immediately after PT and remained elevated throughout the 40-min observation period (all p < 0.001). PSS increased significantly during the first 20 min (all p < 0.02) before returning to baseline. Conclusions: A single PT application was associated with transient increases in MM and sustained elevations in SmO₂, along with associated subjective sensations. These time-associated changes suggest that PT may enhance local muscle perfusion and therefore contribute to the understanding of its physiological mechanisms. Full article

Background: Obstructive sleep apnoea (OSA) is a highly prevalent yet underdiagnosed disorder in patients with cardiovascular disease. Growing evidence suggests a pathophysiological link between OSA and coronary artery disease (CAD); however, the relationship between OSA severity and anatomical complexity of coronary lesions remains incompletely understood. Aim: The aim of this study is to assess the prevalence of OSA in patients undergoing coronary angiography and to evaluate the association between sleep-disordered breathing parameters and the severity of CAD expressed by the SYNTAX score. Methods: This prospective study enrolled 103 consecutive patients referred for invasive coronary angiography. All participants underwent overnight type III cardiorespiratory polygraphy. OSA severity was classified according to the Apnea–Hypopnea Index (AHI). The anatomical complexity of CAD was assessed using the SYNTAX score. Linear regression analyses were performed to determine associations between polysomnographic parameters and SYNTAX score. Results: Significant CAD was diagnosed in 74.8% of patients. OSA was highly prevalent, with severe OSA observed in 36.4% of patients with significant CAD compared to 3.8% in those without significant stenoses (p = 0.003). Patients with significant CAD had higher AHI (18.8 vs. 13.5 events/h; p = 0.003), higher oxygen desaturation index (ODI) (19.3 vs. 12.9 events/h; p = 0.003), and greater mean oxygen desaturation (4.1% vs. 3.8%; p = 0.008). In multivariable regression analysis, AHI (B = 0.329; 95% CI [0.083, 0.576]; p = 0.009) and nicotinism (B = 8.693; 95% CI [2.573, 14.814]; p = 0.006) independently predicted higher SYNTAX scores. Interestingly, each 1% increase in snoring percentage was associated with a 0.203-point reduction in SYNTAX score (95% CI [−0.339, −0.068]; p = 0.004). Conclusions: OSA is highly prevalent in patients undergoing coronary angiography and is independently associated with greater anatomical complexity of CAD. Sleep-disordered breathing, particularly AHI and nocturnal hypoxemia, may represent important non-traditional risk markers of advanced coronary atherosclerosis. Systematic screening for OSA should be considered in patients with suspected or confirmed CAD. Full article

Acute myocardial infarction (AMI) results from a lack of oxygen supply to the myocardium, leading to the loss of cardiomyocytes and their replacement with fibrotic scar tissue. This process is closely associated with the development of heart failure. Regenerative medicine has emerged as a promising strategy to enhance treatment outcomes in severe cases of heart failure. This study aimed to evaluate myocardial regeneration after AMI using a biomaterial composed of mononuclear stem cells and human amniotic membrane. A total of 120 Wistar rats were subjected to experimentally induced AMI. On the 7th day post-infarction, rats with an ejection fraction of <50% on echocardiography were randomized into four groups: (1) control; (2) stem cells; (3) amniotic membrane; and (4) amniotic membrane combined with stem cells. On the 30th day, the surviving animals underwent a second echocardiographic evaluation and were subsequently euthanized. The group treated with the combination of amniotic membrane and stem cells showed reduced systolic and diastolic ventricular volumes. Histological analysis revealed that these animals exhibited less fibrosis and a lower percentage of type I collagen. Based on the results of the study, it was concluded that the combination of human amniotic membrane and mononuclear stem cells decreased ventricular volumes and myocardial fibrosis, suggesting more favorable ventricular remodeling in this experimental model. Full article

Background: The breathing cycle consists of abdominal breathing (AB), for which the diaphragm is responsible, and thoracic breathing (TB), generated by the intercostal muscles. Contraction of the two portions of the diaphragm accounts for 80% percent of inspiration. While bilateral diaphragmatic paralysis causes severe shortness of breath, hemidiaphragm paralysis (HDP) gives fewer symptoms at rest, making it difficult to recognize and diagnose. Because this condition is rare, little is known regarding its consequences on breathing efficiency. Hypothesis: Based on previous studies, we hypothesized that body positions substantially affect the efficiency of breathing in a patient with unilateral hemidiaphragm paralysis and the corresponding physiological parameters. Aims: To measure and compare the amplitudes of abdominal and chest movements in different body positions in an individual with HDP and measure parameters indicating breathing efficiency. Patient and Methods: The patient had HDP due to iatrogenic phrenic nerve injury. Changes in the circumference of the abdomen and chest were measured during inhalation and exhalation with respiratory plethysmography belts (placed on standardized reproducible positions on the chest and abdomen) in different body positions: sitting (SI), standing (ST), lying (SU) and prone (PR). Breathing frequency was calculated, and blood oxygen saturation (SpO₂) was measured with a pulse oximeter. Results: The percentage (%) contributions of abdominal breathing were SI: 16.0; ST: 50.3; SU: −53.5; PR: 1.1. A negative sign shows paradoxical breathing. Blood oxygen saturation (SpO₂) in the four positions was SI: 93%; ST: 93%; SU: 82%; and PR: 82%, whereas the respiratory rate (1/min) was SI:19.4; ST: 15.0; SU: 37.5; PR: 35.9. Conclusions: Body position markedly influences the relative contributions of abdominal and thoracic breathing and overall respiratory efficiency in patients with hemidiaphragm paralysis; abdominal breathing in the supine and prone positions is greatly reduced leading to decreased blood oxygen saturation, a compensatory increase in respiratory rate, and severe dyspnea even at rest. Full article

The performance of biological wastewater treatment processes directly impacts water resource recycling and ecological safety. This year-long study compared full-scale wastewater treatment plants (WWTPs) using either the anaerobic/anoxic/aerobic (AAO) or modified Bardenpho process. By integrating water quality analysis with 16S rRNA sequencing, we examined how process type, influent quality, and seasonal factors affect microbial communities and treatment performance. Systems with high chemical oxygen demand (COD) and biochemical oxygen demand (BOD)/COD influent exhibited the best pollutant removal performance, with average nitrogen and phosphorus concentrations in the effluent as low as 7.0 mg/L and 0.1 mg/L, respectively. Optimizing a 1:9 influent distribution ratio between the pre-anoxic and first anoxic zones in the modified Bardenpho process increased total nitrogen (TN) removal efficiency by an average of 14 percentage points compared to the AAO process. Additionally, the modified Bardenpho process identified 1100 bacterial genera, indicating a more complex and stable community. Influent water quality had the most significant impact on microbial communities and treatment efficiency, followed by seasonal factors and process type. This study provides theoretical and data support for the optimization of wastewater treatment processes and seasonal regulations. Full article

This research evaluated the efficacy of using two types of biochar (non-modified and acidified) from date palm residues (fronds, leaves, pits) as soil amendments for enhancing soil fertility and maize growth. These biochars were produced through slow pyrolysis under oxygen-limited conditions at 500 °C. Our innovative approach was to minimize gas emissions by converting smoke into liquid fertilizer (LS), which was expected to improve seed germination and early plant growth stages. To assess this aim, a completely randomized experiment was conducted under lab conditions, in which 10 maize seeds were placed on double filter papers in Petri dishes and then exposed to seven concentrations of LS (0.0, 0.01, 0.10, 1.0, 10 and 100%, using distilled water for dilution v/v). The LS contains nutrients and bioactive compounds that may enhance seed germination and early plant growth at low concentrations, whereas higher concentrations may cause phytotoxic effects. Results showed that liquefied smoke at 0.1% increased the absolute percentage of maize germination from 75% (control) to 100% and achieved the highest root length of 9.80 cm. Acidified biochars at 5% reduced soil pH from 8.87 to 8.12 and enhanced potassium availability to 87.93 mg kg⁻¹. Conversely, the non-modified biochars contributed to further increases in soil organic matter (up to 1.02%), nitrogen, and phosphorus. In addition, the application of acidified leaf biochar (5%) enhanced maize shoot growth by 133%, chlorophyll content by 39%, and potassium uptake by 110%. This research establishes a scalable approach for converting agricultural waste into climate-resilient resources, effectively addressing soil degradation in arid environments, boosting crop resilience, and furthering the objectives of a circular bioeconomy. Full article

Background and Objectives: Obesity affects over 1.9 billion adults globally, with a disproportionately higher prevalence in Saudi Arabia among women. While excessive adiposity is known to impair respiratory mechanics and lung function, its relationship with respiratory muscle strength and exercise energy expenditure remains inadequately elucidated. This study examined differences in respiratory muscle strength, metabolic equivalents (METs) of physical activity, and energy expenditure during exercise between adults with normal and high body fat percentage (BF%) and explored the statistical role of body fat as a potential mediator in the cross-sectional association between respiratory muscle strength and energy expenditure. Methods: In this cross-sectional study, 126 Saudi women aged 18–45 years (mean age: 21.7 ± 4.2 years) were stratified into normal (n = 63) and high (n = 63) BF% groups. Body composition was assessed via bioelectrical impedance analysis, and respiratory muscle strength (MIP and MEP) was measured using a MicroRPM device. Peak oxygen consumption (VO_2peak) and energy expenditure were obtained through the Bruce Submaximal Treadmill Protocol, and physical activity was self-reported via the IPAQ. Hierarchical regression and structural equation modeling were used to examine variable associations and explore statistical mediation patterns. Results: Participants with high body fat demonstrated significantly low MIP (−26%) and MEP (−31%), low VO_2peak (−13%), and approximately 26% high energy expenditure during exercise compared to the normal-BF group (all p < 0.001), despite comparable self-reported physical activity levels. Body fat percentage was the most strongly associated with energy expenditure (β = 0.078, R² = 0.329), with maximal inspiratory pressure contributing an additional 7.3% of explained variance in hierarchical regression (total R² = 0.414). Mediation analyses revealed that body fat percentage was statistically consistent with a partial mediation model in the relationship between MIP and energy expenditure (indirect association = −0.016, p = 0.033), accounting for 27% of the total association, and between MEP and energy expenditure (indirect association = −0.013, p = 0.035), accounting for 38% of the total association. Conclusions: High BF% is independently associated with low respiratory muscle strength and high exercise metabolic cost. Body fat is statistically associated with (and consistent with a mediating role in) an inverse relationship between respiratory muscle strength and energy expenditure. Alternative directional relationships and shared underlying factors may explain these observations. Full article

Objectives: To quantitatively evaluate the inhibitory effects of commercially available probiotic formulations (Probien, Enterogermina, Reflor) applied as intracanal medicaments against mature dual-species biofilms of Enterococcus faecalis (E. faecalis) and Candida albicans (C. albicans) using a qPCR-based in vitro root canal model, with calcium hydroxide included as the reference intracanal medicament for comparison. Materials and Methods: Root canal specimens containing mature dual-species biofilms were medicated with probiotic–poloxamer gel formulations (Probien, Enterogermina, or Reflor) or calcium hydroxide (reference inhibitory control); infected but untreated canals served as the non-inhibitory control, and sterile non-inoculated specimens were included to confirm procedural sterility. After a 7-day intracanal application period, microbial loads were quantified at baseline and post-treatment by qPCR, and results were expressed as delta cycle threshold (ΔCt), colony-forming equivalents (CFE/mL), and percentage reduction values. Results: A total of 78 specimens (n = 13 per group) were analyzed. No significant intergroup differences were found in E. faecalis ΔCt or reduction percentages (p > 0.05), indicating its persistence despite intracanal medication. For C. albicans, differences among groups were significant (p < 0.001). Calcium hydroxide showed the strongest antifungal effect, producing marked ΔCt and CFE reductions versus probiotic and positive control groups, whereas probiotic formulations displayed only limited antifungal activity and no measurable inhibition against E. faecalis. Conclusions: Under the conditions of this in vitro model, the tested commercially available probiotic formulations—originally developed for gastrointestinal use—did not demonstrate significant antimicrobial effects against mature E. faecalis–C. albicans biofilms. These findings should be interpreted in the context of the absence of probiotic formulations specifically designed for intracanal use and the distinct ecological characteristics of the root canal system, which represents a closed, low-oxygen environment dominated by hard-tissue surfaces. Rather than excluding the potential of probiotics in endodontics, the present results highlight the need for root canal–adapted probiotic strains and delivery strategies tailored to intracanal conditions. Clinical Relevance: This in vitro study provides experimental insight into the limitations of directly applying commercially available gastrointestinal probiotic formulations within the root canal system. The findings highlight the importance of developing root canal–specific probiotic strains and delivery strategies tailored to the unique ecological conditions of the intracanal environment, thereby informing future translational and experimental research in biological endodontics. Full article

Recent climate changes worldwide have negatively impacted crop yields, highlighting the urgent need to develop new cultivation strategies to counteract this phenomenon. Our study aimed to analyze the effects of saline (0 mM, 100 mM, 200 mM, and 300 mM NaCl) and heat stress (24 °C and 32 °C) on the physiological parameters of Chenopodium quinoa variety “Regalona,” evaluating the efficacy of the microalgal biostimulant Chlorella vulgaris-like extract (0%, 0.025% and 0.05%). Sprouts grown under these different conditions were assessed for antioxidant content, antioxidant activity, reactive oxygen species, and photosynthetic pigments. The analyses did not reveal significant effects of the two microalgal concentrations on germination percentage or sprout length across the various temperature and salinity conditions. However, antioxidant activity was increased in many experimental trials, especially when the microalgae were combined with salt stress, with the higher biostimulant concentration showing more pronounced effects. Conversely, a temperature of 32 °C negatively impacted the parameters measured. These findings provide a basis for further research aimed at enhancing the antioxidant and nutraceutical properties of plants valuable for human nutrition. Full article

In this study, a three-dimensional simulation of a walking-beam reheating furnace was developed to improve the steel slab reheating process and reduce surface oxidation kinetics using computational fluid dynamics (CFD). Combustion, heat transfer, fluid dynamics, and chemical reaction models were integrated into the numerical framework of this study. In addition, dynamic mesh remeshing was coupled through user-defined functions (UDFs), enabling the simultaneous simulation of slab movement and evolution of the involved transport phenomena. Turbulence was modeled with the realizable k-ε formulation, combustion with the Eddy Dissipation model, and radiation with the P-1 model coupled with WSGGM to include CO₂ and H₂O gas radiation. Scale formation was modeled using customized functions based on Arrhenius-type kinetics and Wagner’s oxidation model, evaluating its growth as a function of time, temperature, and furnace atmosphere. The predicted thermal evolution inside the furnace was validated using industrial data, yielding an average deviation of 5%. Furthermore, the proposed operating conditions led to an average slab temperature of 1289.77 °C at the exit of the homogenization zone, which was 16 °C higher than that under the current operation but still within the target range (1250 ± 50 °C). The reduction in combustion air decreased energy losses and improved product quality, lowering the molar oxygen content in the furnace atmosphere from 4.9 × 10² mol to 6.7 × 10¹ mol. Additionally, annual savings of 4,793,472 kg of natural gas and 13,884 tons of steel were estimated owing to reduced oxidation losses. The proposed air–fuel adjustment led to estimated annual energy savings (equivalent to 4,793,472 kg of natural gas) and a reduction in material loss due to oxidation from 4.5% to 3.75% (an absolute reduction of 0.75 percentage points; relative reduction ≈ 16.7%), which has a significant industrial impact on metal conservation and descaling cost reduction. Although there are CFD studies on plate overheating and scale growth separately, this work presents three main contributions: (1) the integration, within a single numerical framework, of combustion, radiation, species transport, oxidation kinetics, and actual plate movement using a dynamic mesh; (2) validation against continuous industrial records (16 thermocouples) and quantification of operational benefits such as fuel savings and reduced material loss; and (3) a comparative analysis between actual and optimized conditions, which standardize the air–methane ratio. Full article

Moist chilling is widely used to overcome seed dormancy in zoysiagrass (Zoysia japonica Steud.), but the coordinated physiological and molecular basis remains unclear. Here, freshly matured seeds were subjected to moist chilling at 4 °C in darkness for 0 (Control), 1 (CS1), 2 (CS2), 3 (CS3), or 4 weeks (CS4) and then transferred to germination conditions (30/20 °C, day/night). Prolonged moist chilling progressively improved dormancy release: final germination percentage increased from 40.5% (Control) to 73.5% (CS4), accompanied by a higher germination index and earlier, faster cumulative germination dynamics. Moist chilling also enhanced early seedling vigor, with stronger treatment differentiation in root elongation than in shoot growth. Physiologically, abscisic acid (ABA) content declined while gibberellic acid (GA) content increased, resulting in an elevated GA/ABA ratio with prolonged chilling. Metabolic activation was evidenced by increased α-amylase activity, greater soluble sugar and soluble protein accumulation, and stimulated oxygen uptake. In addition, CAT, SOD, and POD activities were enhanced under prolonged moist chilling, whereas H₂O₂ levels remained relatively stable, suggesting that redox adjustment during dormancy release was characterized by strengthened antioxidant buffering rather than pronounced oxidative accumulation. qRT-PCR supported a mechanistic transition from dormancy maintenance to germination execution, showing moist chilling-associated regulation of ABA/GA metabolism and signaling genes (e.g., NCED, CYP707A, ABI3/ABI5, and GA20ox) and downstream metabolic modules (e.g., GAMYB, AMY, ISA, INV, and HXK1), together with concurrent modulation of respiration- and ROS-related markers (e.g., AOX1a, RBOH, and CAT). Correlation analysis linked germination performance most strongly with α-amylase activity, oxygen uptake, and the GA/ABA ratio. Collectively, our data support a working model in which moist chilling rebalances the ABA–GA gate and activates downstream metabolic and redox adjustment modules to promote dormancy release and improve germination performance in zoysiagrass, providing practical markers for optimizing seed establishment through moist chilling treatment. Full article

Background: Pulse oximetry is widely used to estimate arterial oxygen saturation, yet accuracy may vary for a number of reasons. Data on children with functionally univentricular circulation are limited. The primary aim of this study was to evaluate the agreement between arterial oxygen saturation measured by blood gas and pulse oximetry in children with functionally univentricular circulations. Methods: A retrospective analysis was performed of paired arterial blood gas and pulse oximetry oxygen saturation measurements following Norwood, Glenn, or Fontan procedures. Signed difference was defined as arterial oxygen saturation by blood gas—arterial oxygen saturation by pulse oximetry. Bland–Altman analyses, multivariable regressions, and generalized additive modeling were performed. Results: Mean bias was −4.9 percentage points, indicating pulse oximetry overestimated arterial saturation. The 95% limits of agreement were wide, from −20.7 to 10.8. The agreement was similar in Black and White patients. Fontan physiology demonstrated reduced overestimation by pulse oximetry by multivariable regression. Nonlinear modeling demonstrated more bias in agreement at lower arterial oxygen saturation levels, with arterial oxygen saturation levels explaining 50% of the variance. Conclusions: In functionally univentricular patients, pulse oximetry using the Nellcor MAXN-NS pulse oximeter (Medtronic, Dublin, Ireland) systematically overestimates arterial saturation, particularly in the setting of hypoxemia. Saturation level, rather than race, was the dominant determinant of bias. Full article

Cardiometabolic abnormalities, which are common in diabetes patients, can be alleviated through exercise. We examined the specific effects of walking (4–5 METS) on diabetic patients’ cardiac function in a randomized study. Patients with type 2 diabetes (metformin-, insulin-, and diet-controlled; n = 32) were randomized to a 12-week walking intervention (40 min, three times/week; n = 16) or standard care (control group, n = 16). We prospectively compared metabolic, anthropometric, cardiac function and cardiorespiratory fitness parameters between the two groups via linear regression. Compared with that of the control group, the postintervention global strain of the walking group improved significantly (−19.0 (±3.0) vs. −20.9 (±2.6), Diff = −1.92 (CI = −2.61–−1.24), p < 0.001; control: −18.7 (±3.2) vs. −18.9 (±3.6), Diff = −0.19 (CI = −1.00–0.63), p = 0.650), with a pre/post between-group estimated mean difference of ~−1.73 (CI = −2.78–−0.69; p < 0.001). Abdominal circumference (−3 cm (CI = −4.41–−1.59), p < 0.001)), resting heart rate/bpm (−6.50 (CI = −9.69–−3.31, p < 0.001)) and body fat percentage (−2.74 (CI = −4.71–−0.76, p < 0.007)) changed significantly only in the walking group. Spiroergometric data revealed improved oxygen uptake in the walking group vs. the control group: abs_VO2max/L·min⁻¹ (0.19 (0.05–0.33), p < 0.008); rel_VO2max/mL·kg⁻¹·min⁻¹ (2.43 (1.03–3.83), p < 0.001). This first randomized intervention study of supervised walking in patients with type 2 diabetes demonstrated that even moderate-intensity physical activity (such as walking) can improve cardiac function and body composition, reduced waist circumference, and increased oxygen uptake, making it a cost-effective treatment with significant preventive and restorative benefits for cardiac function and body composition in these patients. Full article

This investigation assessed the neurovascular coupling response through integrated assessments of neuronal function [electroencephalography (EEG)], microvascular oxygenation concentrations [functional near-infrared spectroscopy (fNIRS)], and arterial responses [transcranial Doppler ultrasound (TCD)]. The NVC response was assessed in 113 participants (86 females, aged 19–40 years) during visual (“Where’s Waldo?”) and motor (finger tapping) tasks. Block-averaged, time–frequency power was computed from the EEG data, while hemodynamic response functions were obtained from the fNIRS and TCD metrics. Granger causality assessed the predictiveness between EEG-fNIRS-TCD waveforms for each participant and was converted into a percentage of individuals displaying a significant value. Linear models were computed to determine the influence of sex, concussion history, young adulthood age, cardiorespiratory fitness, and mental health/learning disabilities on NVC parameters. During the initial 10 s of task onset, unidirectional predictiveness was weak to very strong for EEG-TCD (range: 47–83%) and fNIRS-TCD (44–92%) relationships; however, very weak to weak predictiveness was seen for the E0EG-fNIRS (0–29%) relationship for both tasks. Aside from known sex-, age-, and fitness-based influences on baseline/peak hemodynamic values (p < 0.050), the addition of concussion history and mental health/learning disabilities had minimal influence on NVC responses (p > 0.050). The findings demonstrated a unidirectional feedforward mechanism from the neuronal and microvasculature to the upstream arteries during task onset. Full article