Search Results (723)

Background: Right-ventricular (RV) involvement is starting to gain recognition in pediatric dilated cardiomyopathy (DCM), but its deformation characteristics and its relationship to functional status remain insufficiently defined. Methods: Twenty-nine children with primary DCM were compared with age- and sex-matched healthy controls. Conventional echocardiography and two-dimensional speckle-tracking echocardiography (2D-STE) were performed. Segmental deformation (basal, mid-ventricular and apical levels) was analyzed using a linear mixed-effects model. Associations between strain indices and advanced functional limitation (NYHA/Ross Class III-IV) were evaluated using exploratory logistic regression and ROC analysis. Results: Children with DCM showed significant impairment in both ventricles. Conventional parameters (TAPSE, tricuspid E/A ratio, RV E′ velocity, and LV ejection fraction) were reduced. Right ventricular strain was significantly lower in DCM compared with controls (p < 0.05). Segmental analysis demonstrated a basal-predominant reduction in RV strain. Right-ventricular free-wall longitudinal strain correlated with RV S′ (r = −0.49), RV E′ (r = −0.46), LVGLS (r = 0.79) and LV ejection fraction (r = −0.63, all p < 0.05). In univariable analysis, RVFWSL predicted advanced functional class (OR 1.13 per 1% decrease, p = 0.026), while LVGLS remained the independent predictor in the multivariable model. A combined model incorporating RVFWSL and LVGLS demonstrated excellent discriminative accuracy (AUC 0.95). Conclusions: Pediatric DCM is characterized by RV involvement with a distinct basal-dominant deformation pattern. Biventricular strain assessment improves the identification of children with advanced functional class and may enhance functional stratification beyond conventional indices. Full article

Wildfire occurrence in arid and semiarid landscapes is increasingly driven by shifts in climatic and biophysical conditions, yet its dynamics remain poorly understood in the mountainous environments of western Saudi Arabia. This study modeled wildfire probabilities across the Aseer, Al Baha, Makkah Al-Mukarramah, and Jazan regions via multisource Earth observation datasets from 2012–2025. Active fire detections from VIIRS were integrated with ERA5-Land reanalysis variables, vegetation indices, and Copernicus DEM GLO30 topography. A random forest classifier was trained and validated via stratified sampling and cross-validation to predict monthly burn probabilities. Calibration, reliability assessment, and independent temporal validation confirmed strong model performance (AUC-ROC = 0.96; Brier = 0.03). Climatic dryness (dew-point deficit), vegetation structure (LAI_lv), and surface soil moisture emerged as dominant predictors, underscoring the coupling between energy balance and fuel desiccation. Temporal trend analyses (Kendall’s τ and Sen’s slope) revealed the gradual intensification of fire probability during the dry-to-transition seasons (February–April and September–November), with Aseer showing the most persistent risk. These findings establish a scalable framework for wildfire early warning and landscape management in arid ecosystems under accelerating climatic stress. Full article

Hemp seeds (Cannabis sativa L.) are a rich source of phenolic compounds with antioxidant and antimicrobial potential. Still, their genotype-dependent variability and ability to enhance antibiotic efficacy remain insufficiently explored. This study compared three Romanian hemp seed cultivars (Lovrin 110, Silvana, and LV 585) extracted by conventional hydroalcoholic extraction (CE) and ultrasound-assisted extraction (UAE) to evaluate their phenolic composition, antimicrobial effects, and synergistic interactions with amoxicillin and miconazole. HPLC identified genotype- and method-dependent differences, with UAE extracts showing substantially higher levels of epicatechin, quercetin, rosmarinic acid, resveratrol, and ferulic acid. These patterns showed stronger antimicrobial inhibition against Gram-positive and Gram-negative bacteria and yeasts, confirmed by MIC, fold-reduction, and percent enhancement assays. The most pronounced synergy occurred in Streptococcus pyogenes, Staphylococcus aureus, Bacillus cereus, and Candida albicans. PCA revealed two dominant phenolic-activity axes: a rosmarinic/resveratrol/ferulic axis associated with potent inhibition in Escherichia coli and C. albicans, and a quercetin-driven axis linked to Gram-positive bacteria. Overall, UAE extracts displayed superior phenolic enrichment and bioactivity, demonstrating that specific phenolic structures—not total phenolic content—govern antimicrobial performance and antibiotic-enhancing potential in hemp seed extracts. Full article

Background/Objectives: To explore the predictive value of pericardial fat tissue (PFT) radiomics for left ventricular (LV) involvement and major adverse cardiac events (MACE) in arrhythmogenic right ventricular cardiomyopathy (ARVC). Methods: In this retrospective multicenter study, LV involvement was assessed using cardiac magnetic resonance (CMR). A radiomic score (RS) derived from PFT was developed to predict LV involvement. The predictive accuracy of the RS was evaluated through receiver operating characteristic (ROC) analysis. Additionally, multivariable Cox regression analysis was employed to assess the prognosis across the entire dataset. Kaplan–Meier survival curves were used to evaluate the association between RS and MACE. Results: A total of 122 patients (mean age, 44 years ± 17; 76 male) were included, 90 for a development set and 32 for an external test set. The RS demonstrated good predictive performance for LV involvement in both the development and external test sets, with area under the curve (AUC) values of 0.771 and 0.785, respectively. Moreover, a high RS (≥−0.38) was independently associated with MACE during a median follow-up of 5 years (hazard ratio, 3.452; p < 0.001). Based on the right ventricular ejection fraction (RVEF) and RS, a simplified risk score was developed to categorize patients into three groups: high-risk (RVEF ≤ 40%, RS ≥ −0.38), intermediate-risk (RVEF ≤ 40%, RS < −0.38 or RVEF > 40%, RS ≥ −0.38), and low-risk (RVEF > 40%, RS < −0.38). Conclusions: The PFT radiomics can predict LV involvement and be associated with MACE in ARVC patients. Full article

Background: Takotsubo syndrome (TTS) often mimics anterior ST-elevation myocardial infarction (STEMI) caused by left anterior descending (LAD) occlusion, yet the two entities differ fundamentally in pathophysiology and mechanical behavior. Two-dimensional speckle-tracking echocardiography (2D-STE) enables detailed assessment of left ventricular (LV) deformation beyond conventional ejection fraction (LVEF). This meta-analysis compared global and regional LV strain patterns in TTS versus LAD-related anterior STEMI during the acute phase. Methods: A systematic search of PubMed, Embase, and Scopus through October 2025 identified observational case–control studies directly comparing TTS and angiographically confirmed anterior STEMI, with LV mechanics assessed by 2D-STE. Random-effects models were used to pool standardized mean differences (SMDs) for LVEF; global longitudinal strain (GLS); apical, mid-ventricular, and basal longitudinal strain (ALS, MLS, BLS); and global radial strain (GRS). Heterogeneity (I²), publication bias (funnel plots, Egger’s test), meta-regression, and leave-one-out sensitivity analyses were performed. Results: Six studies comprising 221 TTS and 290 anterior STEMI patients met the inclusion criteria. TTS patients were older, predominantly female, and had fewer metabolic risk factors, while LV size was comparable. LVEF was significantly lower in TTS (SMD −1.149; 95% CI −2.20 to −0.10; p = 0.032), with stable findings across sensitivity analyses and no evidence of publication bias. GLS, ALS, MLS, and BLS showed only a non-significant trend toward greater impairment in TTS, and these comparisons were limited by marked inter-study heterogeneity. In contrast, GRS was significantly and consistently more reduced in TTS (SMD −1.284; 95% CI −1.59 to −0.98; p < 0.001), indicating more profound global radial dysfunction. Meta-regression showed no significant influence of demographic factors or vendor-specific software on LVEF or GLS differences. Conclusions: Compared with LAD-related anterior STEMI, TTS is associated with more severely depressed LVEF and markedly impaired radial strain, while longitudinal strain differences remain inconclusive and suggest only a potential trend toward greater dysfunction, reflecting the limited and heterogeneous evidence. These findings are consistent with diffuse, stress-induced myocardial stunning in TTS and suggest that 2D-STE may aid differentiation between stress cardiomyopathy and ischemic infarction in the acute setting, although longitudinal strain parameters should be interpreted cautiously and regarded as hypothesis-generating. Full article

Background and Objectives: This study was conducted in order to develop and validate the Latvian version of the Orofacial Aesthetic Scale (OES-LV) and to assess its psychometric properties in patients with aesthetic, functional or no treatment needs. Materials and Methods: The English version of the OES was translated into Latvian following international guidelines for establishing cultural equivalency of instruments. The test group consisted of 101 subjects comprised of those without treatment requirement, with functional impairment (tooth loss) and with aesthetic treatment needs. Internal consistency, test–retest reliability and convergent validity were investigated. Responsiveness was not tested in the current study. Results: The test–retest assessment of this study was performed on 31 subjects and showed intra-class correlation coefficients ranging from 0.80 to 0.81, which was considered to be good. Cronbach’s α was 0.91, demonstrating the strong internal consistency of the scale. Spearman’s rank correlation coefficients between the OHIP and OES scores varied across subgroups, ranging from −0.35 to −0.57 and showed a negative correlation between OES-LV and selected OHIP items. Conclusions: The Latvian OES demonstrated strong psychometric properties, supporting its use in assessing self-perceived orofacial aesthetics, clinical research, prosthodontic evaluation and dental education. Further studies on responsiveness are recommended. Full article

Background/Objectives: Acute lymphoblastic leukemia (ALL) is the most common childhood malignancy with promising survival. ALL treatment involves the use of cardiotoxic anthracyclines. The data for children on new methods of echocardiographic detection of early-onset anthracycline-related left ventricle dysfunction is lacking. Methods: Consecutive children with ALL were prospectively enrolled. The echocardiography was performed after ALL diagnosis and before initiation of anthracyclines (first assessment) and after induction and intensification therapy completion (second assessment). The left ventricle echocardiographic assessment involved conventional two-dimensional (2D) echocardiography, 2D speckle tracing, and three-dimensional (3D) echocardiography with offline analysis for 3D speckle tracing. Results: The preliminary group of 32 children presented with mean time between the first and second assessment of 7.3 ± 1.5 months (min.5.3–max.11.4). All children were treated by the same treatment protocol and received doxorubicin and daunorubicin. The mean cumulative equivalent anthracycline dose was 165.6 ± 54.0 mg/m². Statistically significant differences between the first and the second echocardiography were observed in LV-GLS-2D −24.6 ± 3.3% vs. −21.0 ± 3.3%; p < 0.001, LVEF-3D 59.7 ± 7.3% vs. 55.1 ± 3.0%; p = 0.010, LV-GLS-3D −23.3 ± 5.3% vs. −20.4 ± 2.8%; p = 0.031 and LV-GCS-3D −26.3 ± 5.9% vs. −21.9 ± 3.2%; p = 0.017. The differences in LVEF-2D and LV-GRS-3D were not statistically significant. The decrease of >15% from the first assessment was observed in 9 (28%) in LV-GLS-2D, 8 (25%) in LV-GLS-3D, 11 (34%) in LV-GCS-3D and only in 4 (13%) patients in LV-GRS-3D. Conclusions: Two-dimensional and three-dimensional speckle tracing and 3D-LVEF may be sensitive indicators of subclinical left ventricular function impairment in children treated for ALL with anthracyclines. However, this is a preliminary analysis of the planned cohort; our results should be interpreted with caution. Full article

As the penetration of distributed energy resources (DERs) continues to increase, there is conjecture concerning the power quality implications of the inverters used to interface these DERs with low-voltage (LV) electricity supply networks. As a power electronics converter, inverters are a known source of harmonic emissions. Using a combination of large-scale field measurements, laboratory evaluations of inverter performance, and power system modelling, this study applies an empirical data-driven approach to investigate the impact of small-scale solar PV inverters on LV harmonic distortion magnitudes. This multi-facetted approach, involving field data analysis, laboratory assessments of inverter performance, and power system simulation to evaluate the impact of small-scale DER on harmonic distortion in LV networks, is novel in comparison to other studies, which only utilise one or two of the analysis methods of simulation, laboratory evaluation, or analysis of field measurements but not all three. The analysis of field measurement data collected over the past decade does not indicate any significant changes in harmonic distortion magnitudes that can be attributed to the increasing penetration of DERs. Power system modelling, which incorporates data obtained from laboratory inverter performance evaluations, indicates that, even at very high levels of penetration, the harmonic current emissions from solar PV inverters are only sufficient to add modest levels of harmonic distortion to LV networks, a 0.25% increase in THD for 40% penetration and a 0.62% increase in THD for 100% penetration, providing an explanation for the findings of the field data analysis. Full article

(1) Background: Ventricular arrhythmias (VAs) are a leading cause of morbidity and mortality in ischemic and non-ischemic heart disease. While automated implantable cardioverter–defibrillators (AICDs) are standard treatment for high-risk patients, predicting future VA post-implantation remains limited. This study evaluated echocardiographic and strain parameters for predicting VA risk in AICD recipients. (2) Methods: This retrospective cohort study included patients who underwent AICD implantation at Westmead Hospital, New South Wales, Australia (January 2014–May 2024). Pre-implant transthoracic echocardiograms (TTEs) were analysed for structural and functional parameters, including left-ventricular (LV) ejection fraction (LVEF), LV global longitudinal strain (GLS), mechanical dispersion (MD), and delta contraction duration (DCD). VA events, defined as appropriate AICD shock or anti-tachycardia pacing, were identified from electronic medical records and device checks. Univariate and multivariate Cox regression analyses were performed. (3) Results: Among 242 patients, 98 experienced VA events. Increased LV end-diastolic diameter, indexed LV mass, and right-ventricular basal diameter were associated with VA events (p < 0.05), whilst LVEF and GLS were not. LV dyssynchrony was greater in affected patients (MD 69.2 ms vs. 63 ms, p = 0.036; DCD 288.8 ms vs. 246.4 ms, p = 0.010). DCD was an independent predictor of VA events (HR 1.003; 95% CI: 1.000–1.006; p = 0.022). (4) Conclusions: DCD may improve risk stratification in AICD patients. Full article

Elite 50 m freestyle performance demands targeted interventions for events that may be decided by hundredths of a second. This case study assesses the effectiveness of an individualised in-water resistance training intervention informed by load–velocity (LV) profiling in both profiling metrics and competitive performance, while documenting the training characteristics of an elite 50 m freestyle swimmer (male, 24.8 years) over the 18 months culminating in the Paris 2024 Olympic Games. A coach-led, six-week resisted-swim intervention involved three sessions per week with prescribed velocity-decrement zones targeting technical development, speed-strength, and power while preserving the swimmer’s race stroke rate. Post-intervention LV outputs showed likely improvements in maximal swim speed, of +3.4% and theoretical maximal load, of +13.6%, and competition time improved by 1.3% with a 3.5% improvement in free swimming time (15–45 m). Although limited to a single-athlete design, the observed improvements suggest that individualised, LV-informed resisted swimming using accessible equipment may contribute to enhancements in sprint swimming performance. Full article

Background: Left ventricular (LV) function and lactate dynamics are major prognostic markers after ST-segment elevation myocardial infarction (STEMI). Early identification of patients at risk for impaired LV function or systemic hypoperfusion may improve outcomes. Machine learning (ML) can enhance predictive accuracy beyond traditional statistical methods, yet most prior studies were limited by small sample sizes and categorical outcomes. Methods: We retrospectively analyzed 2132 consecutive STEMI patients admitted to LMU Hospital (2014–2023). After preprocessing, 1608 patients with complete data were included. Thirty-eight demographic, clinical, procedural, and laboratory variables were used to train Decision Tree, Random Forest, and XGBoost regression models for predicting continuous left ventricular ejection fraction (LVEF) at discharge and lactate levels during hospitalization. Model performance was evaluated using mean squared error (MSE), root mean squared error (RMSE), mean absolute error (MAE), coefficient of determination (R²), and mean absolute percentage error (MAPE). Feature importance and Shapley additive explanations (SHAP) were applied for interpretability. Results: Ensemble models outperformed single trees. XGBoost achieved the best performance for LVEF prediction (MSE = 0.008, RMSE = 0.086, MAE = 0.068, R² = 0.35). Lactate prediction showed moderate accuracy (R² = 0.42 for admission and 0.47 for peak levels). Key predictors included cardiogenic shock, left anterior descending (LAD) culprit lesions, and peak lactate. Conclusions: ML enables individualized prediction of LV function and lactate dynamics after STEMI using routinely available clinical and laboratory data. Ensemble models, particularly XGBoost, demonstrated consistent and clinically meaningful predictive performance and generalizability, supporting their potential for early, data-driven risk stratification in acute cardiac care. Full article

The article analyses the hosting capacity of low-voltage (LV) power grids for connecting distributed energy sources (DER), mainly photovoltaic installations (PV), considering technical limitations imposed by power system operating conditions. The main objective of the research was to develop a simple equation that enables the quick estimation of the maximum power of an energy source that can be safely connected at a given point in the network without causing excessive voltage rise or overloading the transformer and line cable. The analysis was performed on the basis of relevant calculation formulas and simulations carried out in DIgSILENT PowerFactory, where a representative low-voltage grid model was developed. The network model included four transformer power ratings (40, 63, 100, and 160 kVA) and four cable cross-sections (25, 35, 50, and 70 mm²), which made it possible to assess the impact of these parameters on grid hosting capacity as a function of the distance from the transformer station. Based on this, the P_HCI indicator was developed to determine the hosting capacity of a low-voltage network, using only the transformer rating and the length and cross-section of the line for the calculations. A comparison of the results obtained using the proposed equation with detailed calculations showed that the approximation error does not exceed 15%, which confirms the high accuracy and practical applicability of the proposed approach. Full article

Background: Exposure to hypoxia is widely used to enhance training adaptations, but its acute effects on cardiac function remain unclear. Exercise-induced cardiac fatigue (EICF), defined as transient impairments in left ventricular (LV) systolic and diastolic function, has been reported after endurance exercise. Whether moderate hypoxia influences EICF, particularly in athletes, is unknown. Methods: Twenty-four healthy men participated: 12 endurance-trained cyclists (T) and 12 untrained individuals (UT). Each completed two exhaustive cycling tests under normoxia (FiO₂ = 20.9%) and moderate normobaric hypoxia (FiO₂ = 14.4%; ~3000 m). Echocardiography was performed at rest and immediately post-exercise to assess LV systolic and diastolic function. Results: Exhaustive exercise reduced LV diastolic function in both groups, with no significant condition-related differences. Under normoxia, early peak filling velocity (Mitral E) decreased by 21.2% in UT and 23.2% in T, and under hypoxia, by 16.2% in UT and 14.9% in T. Global longitudinal strain (LV GLS) became less negative after exercise under normoxia (UT: +25.2%, T: +30.6%) and hypoxia (UT: +24.8%, T: +20.3%). Athletes exhibited slightly less post-exercise systolic impairment under hypoxia than normoxia, reflected by the maintenance of a more negative LV GLS (∆GLS: 6.87 ± 2.65% in normoxia vs. 4.55 ± 1.86% in hypoxia, p < 0.05). Conclusions: Moderate normobaric hypoxia (~3000 m) did not exacerbate EICF in either group. Athletes showed slightly less post-exercise systolic impairment under hypoxia. Moderate hypoxia may modify the cardiac response to exhaustive exercise, but studies with larger samples and direct preload assessment are needed. Full article

Background/Objectives: Cardiovascular disease is the leading cause of mortality in patients with metabolic dysfunction-associated steatotic liver disease (MASLD), which includes simple steatosis (metabolic dysfunction-associated steatotic liver, MASL), metabolic dysfunction-associated steatohepatitis (MASH), and fibrosis. This study aimed to evaluate the association between left ventricular (LV) systolic function, measured by global longitudinal strain (GLS), and liver inflammation and fibrosis in obese patients with MASLD undergoing preoperative evaluation for bariatric surgery. Methods: Intraoperative liver biopsies classified patients into four groups: non-MASLD; MASL; MASH; and MASH with fibrosis. Preoperative transthoracic echocardiography (TTE) was performed, and LV GLS was assessed using automated strain analysis. Results: Ninety-two patients were included: 13 non-MASLD, 34 MASL, 21 MASH, and 24 MASH with fibrosis. Although most patients had normal LV GLS, values were significantly lower in the MASH with fibrosis group compared to the MASL and non-MASLD groups (p = 0.011). In multivariate analysis adjusted for HDL cholesterol and LV mass, LV GLS was associated with inflammation and fibrosis (OR 0.784; 95% CI 0.637–0.965; p = 0.022). Conclusions: LV GLS was significantly lower in patients with MASH and MASH with fibrosis and was associated with hepatic inflammation and fibrosis in obese individuals undergoing bariatric surgery. Full article

The demand for a reliable power supply is growing. Non-linear loads are becoming more numerous, so supply cables must be carefully selected to consider the skin effect. This article calculates the power losses and cable temperature for different cable arrangements supplying non-linear loads. Power losses are determined using the fast Fourier transform (FFT) of the distorted current signal and the current penetration depth method. The temperature distribution is then calculated using finite element analysis (FEA) for selected cases. The results show that cable bundles can be used instead of single cables with a large cross-sectional area because of lower conductor temperatures, lighter cable arrangements, and reduced installation costs. These aspects are important for the sustainable development of the economy, particularly with regard to material usage. Full article