This paper presents a discrete-time sliding mode voltage controller for a DC-DC boost converter. A disturbance estimator is integrated into the controller, ensuring a fast dynamic response and robustness against matched disturbances and parametric uncertainties, such as input voltage fluctuations, load variations and internal nonlinear dynamics that affect system performance. The disturbance estimator improves the rejection of unmeasured perturbations using only local measurements, without requiring additional sensors or complex adaptive structures. A cascade control scheme is adopted, with an inner inductor current loop and an outer voltage regulation loop. Both controllers utilize disturbance-compensated discrete-time sliding mode control strategies. The simulation results validate the effectiveness of the method, comparing it to the optimized discrete-time proportional integral (DT PI) cascade controller, demonstrating precise voltage regulation and tight performance under disturbances.
Tracking dynamic changes in plant leaves using deep learning models represents a new approach to plant trait analysis. Combining deep learning techniques with botany and agronomy can be of great significance in the future. This indeed marks a crucial step towards addressing the increasingly prevalent problems in agriculture, especially considering that the issue of food scarcity represents a real problem we might face in the coming period. In this paper, we present an adaptation of the Speedy Measurement of Arabidopsis Rosette Traits (SMART) program - a robust, parameter-free system for plant image segmentation and trait extraction. Our goal was to optimize performance on a diverse dataset that differs significantly in characteristics from the one originally used to evaluate SMART. To this end, we replaced the traditional feature extraction methods with a custom-designed semantic segmentation approach. This modification enabled significantly improved results on our target dataset. Furthermore, the enhanced model offers promising potential for future applications, particularly in estimating plant developmental stages.
This research analyses the influence of welding parameters in pulsed TIG welding on the electrical response of the welding power source, and consequently on heat input and weld geometry. In the experiment, we varied pulse frequency and the proportion of base current. By measuring welding current and arc voltage, we analysed the response of welding power source, determined heat input, and examined weld geometry. The results show that, particularly at higher pulse frequencies, the welding power source fails to follow the intended pulse shape and fails to achieve set values of welding current. This directly affects heat input and weld geometry. Increasing pulse frequency up to 5 kHz results in higher weld penetration depths and weld width, mainly due to higher heat input.
Abstract Parabens, often used as preservatives in consumer products, have raised concerns due to their endocrine-disrupting properties. The aim of this study was to quantify the levels of methyl and propyl paraben in adult urine samples and to assess potential health risks. Using high-performance liquid chromatography (HPLC), methyl and propyl parabens were detected in 20 participants at different concentrations. Methylparaben was more prevalent than propylparaben. Risk assessment was performed by calculating the estimated daily intake (EDI) and the hazard quotient (HQ), with HQ values indicating no significant health risk for the participants. Although current exposure levels appear to be safe, the long-term effects of chronic exposure remain uncertain, highlighting the need for further research. This preliminary study provides insight into paraben exposure in adults and contributes to the growing literature on the safety and prevalence of parabens.
Occlusive cervical artery dissection (CeAD) is associated with worse patient outcome. The net clinical benefit of acute revascularization measures has to be weighed against the likelihood of spontaneous recanalization. Our aim was to assess the hitherto un-addressed impact of spontaneous recanalization on stroke risk in patients with occlusive CeAD. MRI verified CeAD patients with initially occlusive CeAD within cohort study that did not undergo acute revascularization measures were assessed. Follow-up data derived from clinical routine and study specific assessments. Outcomes of interest were occurrence of (i) recanalization and (ii) ischemic stroke upstream of CeAD-related occlusion. Adjusted logistic regression analysis addressed the impact of recanalization on said outcomes. 97/328 (29.6%) patients had occlusive CeAD and did not undergo acute revascularization treatment. Upon follow-up, 56/97 (57.7%) showed spontaneous recanalization of initially occlusive CeAD. Female sex (OR 0.41[0.18, 0.97]; P = 0.043) and internal carotid artery dissection (OR 0.33[0.14, 0.78]; P = 0.012) were the only factors independently associated with recanalization. Within a median follow-up of 8.2 (1.58, 12.8) years, a total of 18/97 (18.6%) patients suffered ischemic stroke upstream of the initially CeAD-affected vessel. After adjusting for confounders, spontaneous recanalization was independently associated with lower rates of cerebral ischemia upon follow-up (OR 0.28[0.09, 0.90]; P = 0.032), most notably also independent of type of antithrombotic treatment. Spontaneous recanalization in occlusive CeAD is associated with lower rates of stroke upon follow-up. These results indicate that persistent CeAD-related occlusion remains a risk-factor for recurrent ischemic events, thus calling for future trials addressing optimal medical treatment. N/A. Lukas Mayer-Suess.
Background/Objectives: Renal failure (RF) and systolic heart failure (sHF) are very often associated with each other, and their synergistic influence can affect the prognosis of acute pulmonary embolism (aPE) patients. The aim of this study is to evaluate the associations between RF, sHF, and in-hospital mortality in patients with normotensive aPE. Methods: We analyzed data from the Regional PE Registry (REPER), and 1968 patients with CT pulmonary angiography-confirmed aPE who had a systolic blood pressure of 100 mmHg and higher, and for whom creatinine blood levels and left ventricular ejection fraction (LVEF) were measured at admission to hospital were enrolled. The patients were divided into four groups: the first group comprised patients without renal and systolic heart failure, the second those with RF (creatinine clearance less than 60 mL/min), the third those with sHF (LVEF less than 50%), and the fourth those with both RF and sHF. The primary endpoint of this study was in-hospital all-cause mortality. Results: There are significant differences between in-hospital mortality among the groups: 38/1247 (3.0%) vs. 63/514 (12.9%) vs. 10/99 (10.1%) vs. 20/108 (18.5%) (p < 0.001). In the multivariable regression model adjusted for age, right ventricular dysfunction, and troponin levels, the presence of renal failure, sHF, and both were independently associated with in-hospital all-cause mortality with ORs of 3.59 (95%CI 2.04–6.30, p < 0.001) vs. 3.97 (1.71–9.25, p = 0.001) vs. 6.39 (3.15–12.99, p < 0.001), respectively. Conclusions: The association of renal failure and systolic heart failure has a deleterious prognosis in patients with normotensive aPE.
Anomalous origin of the Left Coronary Artery from the Pulmonary Artery (ALCAPA), also known as Bland-White-Garland syndrome, is a rare congenital coronary anomaly with an estimated incidence of 1 in 300,000 live births. While commonly diagnosed in infancy, adult presentations are exceedingly rare and pose significant diagnostic challenges. Delayed diagnosis may result in progressive myocardial ischemia, heart failure, arrhythmias, or sudden cardiac death. Surgical correction is the definitive treatment, with the goal of restoring a dual coronary artery system and preventing irreversible myocardial damage. We present the case of a 30-year-old male with a prior history of non–ST-elevation myocardial infarction who was referred for evaluation of exertional angina and symptoms of heart failure. Transthoracic echocardiography revealed a dilated left ventricle with an ejection fraction (LVEF) of 35%. Coronary angiography and cardiac MDCT identified an anomalous origin of the left circumflex artery (LCx) from the right pulmonary artery (RPA) and a coronary–pulmonary artery fistula involving the LAD. The patient underwent successful surgical correction with reimplantation of the LCx into the ascending aorta. Postoperative recovery was uneventful. At 3-month follow-up the patient was symptom-free, though echocardiography revealed persistent LV dilation and reduced LVEF, necessitating continued pharmacologic therapy and monitoring. This case highlights the importance of maintaining a high index of suspicion for ALCAPA in adult patients with unexplained cardiomyopathy or ischemic symptoms. Early diagnosis and surgical intervention remain crucial for improving long-term outcomes and preventing life-threatening complications.
OBJECTIVES The primary aim of this study is to detect and quantify the presence of Sildenafil (SDF) and Tadalafil (TDF) in dietary supplements marketed as natural sexual enhancers in Bosnia and Herzegovina. Additionally, the study seeks to utilize these findings to inform relevant authorities, enabling further testing in reference laboratories and prompting the necessary actions to remove these adulterated products from the market. METHODS Using high-performance liquid chromatography with diode array detection (HPLC-DAD), 20 samples were analysed for the PDE-5 inhibitors. RESULTS The analysis revealed that seven of the samples contained either SDF or TDF, with mean concentrations ± standard deviation (SD) ranging from 2,075.57 ± 0.47 µg/g to 33,808.857 ± 99.43 µg/g, and TDF concentrations ranging from 24.16 ± 0.11 µg/g to 3,994.66 ± 6.95 µg/g. CONCLUSION These findings indicate a significant health risk posed by the adulteration of these products. The widespread presence of these active pharmaceutical ingredients (APIs) in products falsely labelled as natural underscores the urgent need for stringent regulatory oversight and enhanced quality control measures to protect consumer safety. This study adds to the growing body of evidence concerning the adulteration of dietary supplements and emphasizes the critical importance of regulatory compliance and monitoring in safeguarding public health.
The journal retracts the article titled "Resilience and Perceived Social Support in Cancer Survivors: Validity, Levels, and Sociodemographic Correlates of CD-RISC-25 and MSPSS Scales" [...].
OBJECTIVE The optimal management of patients with asymptomatic (AsxCS) and symptomatic (SxCS) carotid stenosis is controversial and includes intensive medical management (i.e., best medical therapy [BMT]) with/without an additional carotid revascularization procedure (i.e., carotid endarterectomy [CEA], transfemoral carotid artery stenting [TFCAS] or TransCarotid Artery Revascularization [TCAR]). The aim of this international, expert-based, multispecialty Delphi Consensus document was to reconcile the conflicting views regarding the optimal management of AsxCS and SxCS patients. METHODS A three-round Delphi Consensus process was performed including 63 experts from Europe (n=37) and the United States (n=26). A total of 6 different clinical scenarios were identified involving patients with either AsxCS or SxCS. For each scenario, 5 treatment options were available: (i) BMT alone, (ii) BMT plus CEA, (iii) BMT plus TFCAS, (iv) BMT plus TCAR, or (v) BMT plus CEA/TFCAS/TCAR. Differences in treatment preferences between U.S. and European participants were assessed using Fisher's Exact Test, and odds ratios were used to quantify the magnitude and direction of association. Consensus was achieved when >70% of the Delphi Consensus participants agreed on a therapeutic approach. RESULTS Most participants concurred that BMT alone is not adequate for the management of a 70-year-old fit male or female patient with 80-99% AsxCS (52/63; 82.5% and 45/63; 71.5%, respectively). In contrast, most panelists would opt for BMT alone for an 80-year-old male AsxCS patient with several co-morbidities (48/63; 76.2%). The majority of participants would opt for BMT plus a carotid revascularization procedure for an 80-year-old male SxCS patient with a recent ipsilateral cerebrovascular event, an ipsilateral 70-99% SxCS and a 5-year predicted risk of ipsilateral ischemic event of 10% (54/63; 85.7%), 15% (59/63; 93.6%), or 20% (63/63; 100%). The opinion of U.S.-based participants varied from that of Europe-based respondents in some scenarios. CONCLUSIONS The panel agreed that BMT alone is insufficient for most patients with SxCS, and that select subgroups of AsxCS patients may also benefit from revascularization, especially when high-risk features are present. Patients should be stratified according to their predicted stroke risk, as well as their individual clinical/anatomical/imaging features and should be treated accordingly.
Introduction: The risk of cognitive impairment, including dementia and moderate cognitive impairment (MCI), is higher in patients with diabetes and prediabetes. The need for early diagnosis biomarkers has increased due to the rise in the prevalence of type 2 diabetes mellitus (T2DM) and its related cognitive problems worldwide, as well as the lack of clear biochemical indicators and efficient treatments for dementia or cognitive decline. Chronic low-grade inflammation, reflected by elevated complete blood count-derived inflammatory indices (CBCIIs), has been implicated in both metabolic dysregulation and neurodegeneration. However, their relationship with cognitive impairment in T2DM remains insufficiently explored. The objective of this study was to investigate the association between CBCIIs and cognitive function in patients with T2DM. Methods and materials: This cross-sectional observational study included 116 patients with T2DM recruited from diabetes counseling centers in the Public Institution Health Center of Sarajevo Canton, Bosnia and Herzegovina. Based on the assessed cognitive status, patients with T2DM were divided into two groups: with cognitive impairment (n= 76) and without cognitive impairment (n=40). A validated assessment tool, the Montreal Cognitive Assessment (MoCA), a quick test designed to screen for milder forms of cognitive impairment, was used for cognitive screening. Venous blood samples were analyzed for standard complete blood count parameters, from which 11 CBCIIs were calculated: neutrophil-to-lymphocyte ratio (NLR), derived NLR (dNLR), neutrophil-to-platelet ratio (NPR), neutrophil-to-lymphocyte-to-platelet ratio (NLPR), platelet-to-lymphocyte ratio (PLR), monocyte-to-lymphocyte ratio (MLR), systemic immune-inflammation index (SII), aggregate index of systemic inflammation (AISI), systemic inflammation response index (SIRI), lymphocyte-to-monocyte ratio (LMR), and monocyte-to-neutrophil ratio (MNR).. Results: The results of our study showed that NLR, dNLR, NPR, NLPR, PLR, MLR, SII, AISI, and SIRI were significantly higher in the group of T2DM patients with cognitive impairment compared to the group without cognitive impairment. On the other hand, LMR and MNR were significantly lower in the group of T2DM patients with cognitive impairment compared to the group without cognitive impairment (p<0.05). The MoCA score was significantly negatively correlated with NLR, dNLR, NPR, NLPR, and SII, and positively with MNR (p<0.05) Conclusion: Elevated CBCIIs are significantly associated with cognitive impairment in patients with T2DM. These inexpensive and widely available indices may serve as adjunctive markers for early cognitive screening in this population.
The objectives of this study are to determine the prevalence of Staphylococcus aureus in nasal and throat swab samples collected from healthy individuals within a population of workers and students, analyze its frequency in relation to the gender distribution of partici- pants, and assess the antibiotic susceptibility profile. S. aureus was isolated exclusively from nasal swab samples (111/1403). The findings indicate that nasal carriage is significantly more prevalent in male participants than in females and is independent of age. No statistically significant differences in S. aureus prevalence were observed between the worker and student populations. Resistance was detected for: penicillin, ampicillin, amoxicillin/clavulanate, oxa- cillin, cephalexin, gentamicin, erythromycin, chloramphenicol, trimethoprim-sulfamethoxaz- ole and ciprofloxacin. Further research involving a larger sample size and an extended study period is required to elucidate the influence of geographic and sociodemographic factors on S. aureus carriage, as well as the potential impact of gender on the prevalence of resistant strains.
Introduction: Stress is an essential element of students' academic lives, especially as exams approach. Due to academic demands, social pressure, and personal expectations, stress can negatively impact students' mental and physical health and lead to an increased risk of chronic illness. This study investigated the effects of oral exams on students' physiological parameters. Material and Methods: The study involved 35 physiotherapy students. The "Smart Bracelet TK 30" monitored heart rate, blood pressure, and blood glucose levels before and during the exams. Results: Significant blood pressure and pulse changes were observed between resting and exam conditions. Blood glucose levels were higher in men than in women during the exams. Conclusion: Exam stress significantly impacts students' physiological responses. Given the potential long-term health risks, preventive health strategies should be developed to help students cope with academic stress.
Background/Objectives: This study investigates the antimicrobial properties of pomegranate peel extract (PoPEx) and its major polyphenolic constituents against Gram-positive and Gram-negative bacteria, employing six clinical isolates of Staphylococcus aureus and five isolates of Escherichia coli. The study further aims to elucidate mechanisms of action through molecular docking and transport studies. Methods: Chemical composition was analyzed using liquid chromatography–mass spectrometry (LC–MS). Antimicrobial activity was determined by the broth microdilution method. Molecular docking was performed with the AutoDock Vina algorithm, and transport studies through porin channels were carried out using Caver software. Results: PoPEx showed stronger activity against Gram-positive (MICs 15.62–500.00 μg/mL) than Gram-negative bacteria (MICs 125.00–500.00 μg/mL). Punicalagin was most active against S. aureus, while gallic acid was most effective against E. coli. Docking revealed high affinities of punicalagin and punicalin, whereas transport studies highlighted the advantage of smaller phenolics like gallic acid in crossing porins. Conclusions: Larger tannins exhibited strong target binding but limited porin permeability, reducing efficacy in Gram-negative bacteria. These findings provide insights into structure–activity relationships of pomegranate polyphenols and support their potential as natural antimicrobial agents.
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