Search Results (6,171)

Background/Objectives: Pre-discharge NT-proBNP levels may serve as a helpful tool in the algorithm of assessing the long-term risk of mortality after a hospitalization for symptomatic heart failure (HF). The goals were: (a) to identify a cut-off for NT-proBNP concentrations for predicting the two-year all-cause mortality in our sample of patients, and (b) to identify risk factors associated with NT-proBNP concentrations being higher than this cut-off. Methods: The present prospective study included 96 patients diagnosed with symptomatic HF with left ventricular ejection fraction (LVEF) < 50%, who were followed for up to 2 years post-hospital discharge. Results: Levels of pre-discharge NT-proBNP were found to be predictive of all-cause mortality. We determined that an NT-proBNP cut-off score of 8700 pg/mL may predict with 75.8% sensitivity and 70.1% specificity a 4.6-fold increase in mortality risk over a period of two years in our study sample, 95% CI (2–10.8), p = 0.001. Predictors of NT-proBNP concentrations > 8700 pg/mL included: older age, OR 4.73, 95% CI (1.74–12.85), p = 0.002; lack of angiotensin converting enzyme inhibitor (ACE-I) treatment, OR 0.3, 95% CI (0.12–0.74), p = 0.009; low systolic blood pressure (SBP) at admission, OR 3.4, 95% CI (1.36–8.49), p = 0.009; and low serum hemoglobin at admission, OR 3.2, 95% CI (1.38–7.46), p = 0.007. Conclusions: NT-proBNP may serve as a helpful tool for predicting mortality after an episode of HF decompensation, thus allowing the implementation of appropriate long-term monitoring and treatment. Particular attention should be paid to older patients without ACE-I medication, who had SBP < 120 mmHg at admission, and/or low levels of serum hemoglobin—as these patients are more likely to have pre-discharge NT-proBNP concentrations higher than the cut-off. These findings have implications for the long-term community follow-up of patients with HF. Full article

Surface irrigation systems are among the most common yet often inefficient methods due to poor design and management. A key factor in optimizing their design is the accurate prediction of the water advance and infiltration relationships’ coefficients. This study introduces a novel model based on the Beta cumulative distribution function for predicting water advance and estimating infiltration coefficients in surface irrigation systems. Traditional methods, such as the two-point approach, rely on limited data from only the midpoint and endpoint of the field, often resulting in insufficient accuracy and non-physical outcomes under heterogeneous soil conditions. The proposed model enhances predictive flexibility by incorporating the entire advance dataset and integrating the midpoint as a constraint during optimization, thereby improving the accuracy of advance curve estimation and subsequent infiltration coefficient determination. Evaluation using field data from three distinct sites (FS, HF, WP) across 10 irrigation events demonstrated the superiority of the proposed model over the conventional power advance method. The new model achieved average RMSE, MAPE, and R² values of 0.790, 0.109, and 0.997, respectively, for advance estimation. For infiltration prediction, it yielded an average error of 12.9% in total infiltrated volume—outperforming the two-point method—and also showed higher accuracy during the advance phase, with average RMSE, MAPE, and R² values of 0.427, 0.075, and 0.990, respectively. These results confirm that the Beta-based model offers a more robust, precise, and reliable tool for optimizing the design and management of surface irrigation systems. Full article

Background/Objectives: Patients with non-valvular heart failure frequently develop valvular disease. However, the prevalence of valvular disease across patients with different heart failure etiologies remains underexplored. This study aimed to investigate the burden of VHD among patients with non-valvular heart failure, and secondly evaluate its association with cardiopulmonary test. Methods: We analyzed data from patients with non-valvular heart failure (HF) who were evaluated as outpatients at the HF clinic between February 2020 and November 2024. Patients were categorized into three groups: coronary artery disease-related HF (CAD-HF), dilated cardiomyopathy (DCM), and other causes (e.g., hypertension, diabetes, and various cardiomyopathies). Demographic and clinical characteristics, as well as echocardiographic and cardiopulmonary exercise testing (CPET) results, were evaluated. Results: Among all groups mild mitral regurgitation (MR) was the most common valvular disease, followed by mild tricuspid regurgitation (TR). Patients with CAD-HF frequently had mild aortic regurgitation (AR) compared to DCM (23.6% vs. 14.9%, p = 0.05). In the CPET subgroup, which included 41 patients who consented to participate, in patients with moderate-to-severe VHD had significantly lower VO₂/HR (oxygen pulse), VO₂max, and OUES, indicating worsened functional capacity despite similar left ventricular ejection fraction. Hypertension and atrial fibrillation were independently associated with greater valvular disease severity on multivariable analysis. Conclusions: No significant differences in valvular disease between patients with DCM and CAD-HF were documented, apart from a higher prevalence of mild AR in the CAD-HF group. Patients with moderate-to-severe valvular regurgitation demonstrated worse cardiopulmonary performance, regardless of ejection fraction, highlighting the important role of CPET in evaluating the functional impact of valvular heart disease in this population. Full article

To meet gas turbines’ growing demand for high-performance thermal barrier coatings (TBCs), this study addresses the limitations of traditional single-layer 8% Y₂O₃-stabilized ZrO₂ (YSZ) coatings in high-temperature corrosive environments. Atmospheric plasma spraying (APS) was used to fabricate the double-ceramic TBCs with (Sm_0.2Gd_0.2Dy_0.2Er_0.2Yb_0.2)₂(Zr_0.7Hf_0.3)₂O₇ (RHZ) as the outer layer and YSZ as the inner layer; thermal cycling corrosion tests (1000 °C, Na₂SO₄ + V₂O₅ molten salt) were conducted to compare its performance with traditional single-layer YSZ. The results showed that the YSZ corrosion products were m-ZrO₂ and YVO₄, while RHZ/YSZ produced rare-earth vanadates, m-(Zr,Hf)O₂, and t′-(Zr,Hf)O₂, and corrosion degree was positively correlated with salt concentration (which was more impactful) and the number of cycles. Both coatings failed via molten salt penetration, thermochemical reaction, and crack-induced spallation. The corrosion mechanism between the RHZ/YSZ coating and the mixed salt can be explained based on the Lewis acid–base theory and the optical basicity. The RHZ layer on the surface of RHZ/YSZ coatings indeed hinders the penetration of corrosive molten salts into the underlying YSZ layer to some extent. Full article

Cardiovascular diseases (CVDs) cover various pathologies including heart failure (HF). Furthermore, vitamin D is involved in the regulation of the cardiovascular system. This study aimed to assess the association between the vitamin D receptor (VDR) genotypes and the occurrence of cardiovascular disorders in the Algerian population. VDR gene polymorphisms were identified using the PCR-RFLP method. Moreover, plasma concentrations of 25-hydroxyvitamin-D were assessed by a chemiluminescent immunoassay method and plasma NT-proBNP levels were determined in vitro by immunoenzymatic analysis. Interestingly, our results indicate that the genotypic frequencies of ApaI polymorphism of the VDR gene were significantly higher in CVD patients compared to the control group. Moreover, higher numbers of AA genotypes and A alleles were found in the CVD group. Our data indicate that the group of CVD patients with HF compared to those without HF showed the same genotype and allele distribution. Furthermore, low vitamin D rates and high N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels according to the VDR rs7975232 genotype were noted in CVD patients compared to healthy controls. Our results indicate that ApaI polymorphism of the VDR gene and lower vitamin D level may be associated with increased cardiovascular risk. These findings indicate that the ApaI AA genotype could be considered as a new HF risk marker in the Algerian population. Full article

Background: Advanced heart failure (HF) carries high morbidity and mortality, and deterioration on the heart transplantation (HT) waiting list remains a major challenge. Intermittent outpatient levosimendan has been proposed as a bridge strategy, but the optimal regimen and its impact on peri-transplant outcomes remain uncertain. Within a personalized-medicine framework, we targeted a low-output/INTERMACS 3 phenotype and operationalized an adaptable, protocolized levosimendan pathway focused on perfusion/congestion stabilization to preserve transplant candidacy. Methods: We conducted a single-center, retrospective cohort study of 25 consecutive adults actively listed for HT between 2019 and 2024, treated with a standardized outpatient program of a 14-day interval of 6 h intravenous levosimendan infusions (target 0.2 μg/kg/min infusions) continued until transplant. Personalization in this program was operationalized through (i) phenotype-based eligibility (low CI and elevated filling pressures despite GDMT), (ii) predefined titration and safety rules for blood pressure, arrhythmias, and renal function, and (iii) individualized continuation until transplant with nurse-supervised monitoring and review of patient trajectories. Baseline characteristics, treatment exposure and safety, changes in hospitalizations and biomarkers, and peri-transplant outcomes were analyzed. Results: Patients were predominantly male (68%), with a mean age of 47.9 ± 17.5 years and severe LV dysfunction (LVEF 30.6 ± 9.8%). Median treatment duration was 131 days (IQR 60–241). No infusions required discontinuation for hypotension or arrhythmia, and no adverse events were directly attributed to levosimendan. Two patients (8%) died on the waiting list, both unrelated to therapy. During treatment, HF hospitalizations decreased significantly compared with the previous 6 months (48% vs. 20%, p = 0.033), renal function remained stable, and NT-proBNP trended downward. Of the 23 patients transplanted, two (9%) underwent urgent HT during decompensation. Post-transplant, vasoplegia occurred in 26% (n = 6 of 23), and 30-day mortality was 9% (n = 2 of 23). Conclusions: By defining the target phenotype, therapeutic goals, and adaptation rules, this study shows how a standardized but flexible outpatient levosimendan regimen can function as a personalized bridge strategy for low-output advanced HF. The approach was associated with fewer hospitalizations, stable renal function, and acceptable peri-transplant outcomes, and merits confirmation in multicenter cohorts with attention to patient heterogeneity and treatment effect refinement. Full article

Heart failure (HF) is a growing public health concern, driven by the increasing prevalence of obesity, diabetes, and aging. Despite therapeutic advances, HF continues to be associated with high morbidity and mortality. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs), originally developed for glycemic control in type 2 diabetes, have demonstrated cardiovascular benefits in clinical trials. Recent studies, including STEP-HFpEF and SUMMIT, have shown improvement in symptoms and weight loss in patients with HF with preserved ejection fraction (HFpEF). GLP-1 RAs are involved in multiple biological pathways relevant to heart failure pathophysiology. These include pathways related to sympathetic nervous system activity, inflammatory cytokine signaling, oxidative stress, calcium handling, natriuretic peptide signaling, and cardiac metabolism. GLP-1 receptor agonists modulate vascular pathways involving nitric oxide signaling, endothelial function, and renal sodium handling, contributing to improved hemodynamics and neurohormonal balance. Together, these actions intersect with key neurohormonal and cellular processes contributing to chronic heart failure progression. This review explores the mechanistic overlap between GLP-1 receptor signaling and heart failure pathophysiology. This mechanistic overlap suggests a plausible role for these agents as adjunctive treatments in heart failure, especially in metabolically driven phenotypes. While direct cardiac effects remain incompletely defined, systemic metabolic and anti-inflammatory actions provide a mechanistic basis for observed clinical benefits. Full article

Background/Objectives: Obstructive sleep apnea (OSA) is strongly associated with cardiovascular morbidity, and depressive symptoms are common in affected individuals. Both OSA and depression have been linked to autonomic dysfunction, but the independent contribution of depressive symptoms to autonomic dysfunction in OSA remains unclear. We investigated whether depressive symptom severity is associated with autonomic function, indexed by heart-rate variability (HRV), in patients with OSA. Methods: We retrospectively analyzed 1713 adults with OSA at a university-affiliated sleep center from 2011 to 2024. HRV was derived from electrocardiography during polysomnography, and frequency-domain indices (natural log-transformed LF, HF, VLF, TP, and LF/HF) were computed. Depressive symptoms were assessed using the Beck Depression Inventory-II (BDI-II). Associations between BDI-II and HRV indices were evaluated using univariable and multivariable linear regressions. Results: In univariable regression analyses, higher BDI-II scores were significantly associated with lower HRV indices (ln LF, ln HF, ln VLF, ln TP; all p < 0.01). In multivariable analyses, higher BDI-II scores were independently associated with lower ln LF, ln HF, and ln TP (all p < 0.05), adjusting for age, sex, body mass index, hypertension, diabetes, apnea–hypopnea index, arousal index, and sleep quality. Conclusions: Greater depressive symptom burden is independently associated with reductions in multiple HRV indices, suggesting attenuated parasympathetic activity and autonomic dysregulation in patients with OSA. These findings support integrated management strategies that address both physiological and psychological domains in OSA and motivate longitudinal studies to test whether effective depression treatment improves HRV and mitigates long-term cardiovascular risk. Full article

Background/Objectives: Beetroot supplementation is a rich source of inorganic nitrate and has been proposed to enhance nitric oxide bioavailability and support cardiovascular recovery after exercise. This study aimed to evaluate the effects of beetroot supplementation on post-exercise cardiovascular and autonomic recovery in postmenopausal women. Methods: A systematic review and meta-analysis were conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Searches were performed in PubMed, Scopus, and Web of Science databases from inception to July 2025. Ten trials involving postmenopausal women were included. Outcomes assessed included cardiovascular measures (blood pressure and vascular function), autonomic parameters derived from heart rate variability (HRV)—specifically the root mean square of successive differences (RMSSD), the standard deviation of normal-to-normal intervals (SDNN), and high-frequency power (HF)—as well as physical performance (peak oxygen uptake [VO_2peak or VO_2max] and functional fitness tests). Four independent reviewers extracted data, assessed risk of bias, and evaluated the certainty of evidence using the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) approach. Results: Pooled analyses from two trials (n = 54) revealed a statistically significant improvement in RMSSD with beetroot supplementation (mean difference: 6.68 ms; 95% CI: 0.86 to 12.50; p = 0.02), suggesting enhanced parasympathetic reactivation after exercise. No significant effects were detected for HF (mean difference: 61.75 ms²; 95% CI: −70.92 to 194.43; p = 0.36) or SDNN (mean difference: 6.20 ms; 95% CI: −9.69 to 22.09; p = 0.44). Substantial to considerable heterogeneity was identified across outcomes (I² = 73–86%). Certainty of evidence was rated moderate for RMSSD, low for SDNN, and very low for HF. Conclusions: Beetroot supplementation may enhance post-exercise autonomic recovery in postmenopausal women, primarily through improvements in RMSSD. However, further trials with standardized protocols, larger samples, and longer intervention durations are required to clarify its impact on broader HRV domains, cardiovascular function, and clinical outcomes. Full article

An exposed sedimentary succession, ca 115 m of a total of 1000 m, from the Eastern Carpathian foredeep was, for the first time, analyzed using facies analysis and scale- and time-independent sequence stratigraphy methods to reveal the depositional environment and its cyclic sedimentation. The outcropping deposits, belonging to the Șomuz Formation, dated on the basis of molluscs, foraminifera, and ostracods, are uppermost Volhynian (upper Serravalian). The three recurrent facies associations we have distinguished indicate a storm-dominated shoreface–offshore transition environment. Five-decametre-thick high-frequency sequences (HFS1–5), at most of 4th order, bounded by maximum regressive surfaces, were defined in the studied interval. The maximum thickness of the Volhynian deposits in the area, known both from well sites and outcrops, allowed us to estimate the sedimentation rate at ca 1.5 m/kyr. The fossil content shows that the entire sedimentary succession was deposited in very shallow to shallow water during the whole Volhynian (12.65 - ca 12.01 Ma). The time interval we studied was estimated at ca 75 kyr, so the average time of one HFS is ca 15 kyr. At this scale, considering that both high subsidence and Eastern Paratethys sea-level rise added to accommodation, the sediment supply must have been the main control of cyclic sedimentation, which, in turn, must have been controlled by precession climatic changes in the source area. The estimated time of an HFS is shorter than a precession cycle, but better dating might support or refute this hypothesis. This paper may awaken the interest of the owners of better data, especially from subsurface (seismic, well logs), to complete the data from natural exposures. Full article

This study investigated the physiological effects of seat vibration during prolonged sitting in a simulated autonomous driving environment. Eleven healthy participants (3 young adults and 8 older adults) viewed a 120-min highway driving video under two conditions: rhythmic seat vibration (2 Hz, mimicking natural respiration) and no vibration. Physiological and behavioral metrics—including Psychomotor Vigilance Task (PVT), seat pressure distribution, heart rate variability (HRV), body acceleration, and skin temperature—were assessed across three phases. Results demonstrated that seat vibration significantly enhanced parasympathetic activity, as evidenced by increased HF power and decreased LF/HF ratio (p < 0.05), suggesting reduced autonomic stress. Additionally, seated posture remained more stable under vibration, with reduced asymmetry and sway, while the no-vibration condition showed time-dependent postural degradation. Interestingly, skin surface temperature was lower in the vibration condition (p < 0.001), indicating a possible thermoregulatory mechanism. In contrast, PVT performance revealed more false starts in the vibration condition, particularly among older adults, suggesting that vibration may not enhance—and could slightly impair—cognitive alertness. These findings suggest that low-frequency seat vibration can support physiological stability and postural control during prolonged sedentary conditions, such as in autonomous vehicles. However, its effects on vigilance appear limited and age-dependent. Overall, rhythmic vibration may contribute to enhancing passenger comfort and reducing fatigue-related risks, particularly in older individuals. Future work should explore adaptive vibration strategies to balance physiological relaxation and cognitive alertness in mobility environments. Full article

Background/Objectives: Allophylus edulis, known as “vacum”, is popularly used in Brazil for treating inflammatory diseases, though no scientific evidence supports the anti-inflammatory activity of its leaf infusion. This study aimed to assess the chemical composition, antioxidant and anti-inflammatory properties of the lyophilized infusion (ILAE) of A. edulis leaves, as well as the pharmacological effects of its hydromethanolic fraction (HMf) and the isolated compound vitexin 2″-O-rhamnoside (AE-1). Histochemical analyses of the leaves and in silico toxicity prediction of AE-1 were also performed. Methods: Fresh leaves were used for histochemical analysis and preparation of ILAE. The infusion was fractionated into n-hexane (Hf), ethyl acetate (EAf), and HMf fractions. Total phenols, flavonoids, flavonols, tannins, and antioxidant activity were determined by spectrophotometric methods. AE-1 was obtained from HMf through chromatographic methods and was evaluated by the ProTox model in relation to toxicity predictions (in silico). Anti-inflammatory effects of ILAE (3, 30, 100 mg/kg), HMf (3, 30 mg/kg), and AE-1 (3 mg/kg) were evaluated in carrageenan-induced paw edema, pleurisy, and CFA-induced inflammation in mice. Results: ILAE and its fractions were rich in total phenols (≤177 mg GAE/g) and showed potent antioxidant activity. Histochemical analysis revealed leaf secretory structures. AE-1 showed no hepatotoxic, carcinogenic, mutagenic, or cytotoxic effects in silico. All doses of ILAE and HMf reduced edema, hyperalgesia, and leukocyte migration. ILAE (30 mg/kg), HMf (30 mg/kg), and AE-1 (3 mg/kg) reduced CFA-induced inflammatory responses. Conclusions: ILAE contains polyphenolic compounds with antioxidant, anti-inflammatory, and antihyperalgesic properties, supporting the traditional use of A. edulis and its potential in inflammation-related therapies. Full article

During the grinding process of K9 glass, various forms of surface damage—such as indentations and pitting—as well as subsurface damage—including cracks and residual stress—are generated. This paper focuses on the planetary grinding method utilizing bonded abrasives for both process research and subsurface damage detection. It examines the timeliness of grinding duration and analyzes the effects of abrasive grain size and grinding pressure on surface quality. Building upon the principle of differential etching, an improved HF chemical etching method is proposed to establish a relationship model that correlates the depth of subsurface damage with abrasive grain size, applied pressure, and surface roughness. Full article

Cardiopulmonary Exercise Testing (CPET) is the gold standard for the functional assessment in patients with heart failure (HF), providing objective parameters that reflect the integrated response of the cardiovascular, respiratory, and muscular systems, in addition several CPET-derived variables have shown independent prognostic value in patients with both reduced (HFrEF) and preserved ejection fraction (HFpEF) HF. This review aims to critically analyze the main CPET prognostic variables in heart failure, highlighting their underlying pathophysiological mechanisms, their predictive capacity for mortality and hospitalizations, and their integration into clinical decision-making models. Parameters such as peak oxygen uptake (VO₂), minute ventilation/carbon dioxide production (VE/VCO₂) slope, periodic breathing (or exercise oscillatory ventilation—EOV), anaerobic threshold (AT), oxygen pulse, and VO₂/work slope provide complementary insights into clinical risk; moreover, the combination of multiple CPET variables allows for more accurate risk stratification compared to the isolated use of each parameter. Multiparametric prognostic models such as the Metabolic Exercise Cardiac Kidney Index (MECKI) score, the Seattle Heart Failure Model, and the Heart Failure Survival Score (HFSS) incorporate these variables alongside clinical and laboratory data to guide advanced management and therapeutic decisions, including heart transplantation or left ventricular assistant device (LVAD) implantation. For these reasons, CPET-derived variables are essential prognostic tools in heart failure. Beyond improving risk stratification, their integration into multiparametric models supports a more personalized therapeutic approach, including tailored pharmacological management. Full article

Background/Objectives: Mechanical circulatory support (MCS) is increasingly utilized for the management of acute decompensated heart failure (HF) and cardiogenic shock (CS). The primary goals of MCS are to restore systemic perfusion, reduce cardiac workload, and support end-organ function. A thorough understanding of cardiovascular physiology in patients supported by MCS is essential for clinical decision-making. This review summarizes current evidence on the physiological effects of various MCS devices, key monitoring techniques, patient management, and explores the emerging role of artificial intelligence (AI) in this field. Main Text: Short-term MCS devices include intra-aortic balloon pumps (IABP), percutaneous left-sided devices such as Impella (Abiomed, Danvers, MA, USA) and TandemHeart (LivaNova, London, UK), percutaneous right-sided support devices like Protek Duo (LivaNova, London, UK) and Impella RP Flex (Abiomed, Danvers, MA, USA), and veno-arterial extracorporeal membrane oxygenation (VA-ECMO). Long-term support is mainly provided by left ventricular assist devices (LVADs), including the HeartMate 3 (Abbott Laboratories, Chicago, IL, USA). Optimal MCS application requires an understanding of device-specific cardiovascular interactions and expertise in appropriate monitoring tools to assess device performance and patient response. The choice of device, timing of initiation, and patient selection must be individualized, with careful consideration of ethical implications. The integration of AI offers significant potential to advance clinical care by improving complication prediction, enabling real-time optimization of device settings, and refining patient selection criteria. Conclusions: MCS is a rapidly evolving field that requires a comprehensive understanding of cardiovascular interactions, careful selection of monitoring strategies, and individualized clinical management. Future research should address current device limitations, clarify device-specific clinical applications, and assess the validity of AI-driven technologies. Full article