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Sensors (Basel, Switzerland) Jun 2024This study aimed to address the challenges encountered in traditional bulk wave delamination detection methods characterized by low detection efficiency. Additionally,...
This study aimed to address the challenges encountered in traditional bulk wave delamination detection methods characterized by low detection efficiency. Additionally, the limitations of guided wave delamination detection methods were addressed, particularly those utilizing reflected waves, which are susceptible to edge reflections, thus complicating effective defect extraction. Leveraging the full waveform inversion algorithm, an innovative approach was established for detecting delamination defects in multi-layered structures using ultrasonic guided wave arrays. First, finite element modeling was employed to simulate guided wave data acquisition by a circular array within an aluminum-epoxy bilayer structure with embedded delamination defects. Subsequently, the full waveform inversion algorithm was applied to reconstruct both regular and irregular delamination defects. Analysis results indicated the efficacy of the proposed approach in accurately identifying delamination defects of varying shapes. Furthermore, an experimental platform for guided wave delamination defect detection was established, and experiments were conducted on a steel-cement bilayer structure containing an irregular delamination defect. The experimental results validated the exceptional imaging precision of our proposed technique for identifying delamination defects in multi-layered boards. In summary, the proposed method can accurately determine both the positions and sizes of defects with higher detection efficiency than traditional pulse-echo delamination detection methods.
PubMed: 38931799
DOI: 10.3390/s24124017 -
Diagnostics (Basel, Switzerland) Jun 2024Chronic heart disease (CHD) is a widespread and persistent health challenge that demands immediate attention. Early detection and accurate diagnosis are essential for...
Chronic heart disease (CHD) is a widespread and persistent health challenge that demands immediate attention. Early detection and accurate diagnosis are essential for effective treatment and management of this condition. To overcome this difficulty, we created a state-of-the-art IoT-Based Ambulatory Blood Pressure Monitoring System that provides real-time blood pressure readings, systolic, diastolic, and pulse rates at predefined intervals. This unique technology comes with a module that forecasts CHD's early warning score. Various machine learning algorithms employed comprise Naïve Bayes, K-Nearest Neighbors (K-NN), random forest, decision tree, and Support Vector Machine (SVM). Using Naïve Bayes, the proposed model has achieved an impressive 99.44% accuracy in predicting blood pressure, a vital aspect of real-time intensive care for CHD. This IoT-based ambulatory blood pressure monitoring (IABPM) system will provide some advancement in the field of healthcare. The system overcomes the limitations of earlier BP monitoring devices, significantly reduces healthcare costs, and efficiently detects irregularities in chronic heart diseases. By implementing this system, we can take a significant step forward in improving patient outcomes and reducing the global burden of CHD. The system's advanced features provide an accurate and reliable diagnosis that is essential for treating and managing CHD. Overall, this IoT-based ambulatory blood pressure monitoring system is an important tool for the early identification and treatment of CHD in the field of healthcare.
PubMed: 38928712
DOI: 10.3390/diagnostics14121297 -
Biomedical Journal Jun 2024The high prevalence of desynchronized biological rhythms is becoming a primary public health concern. We assess complex and diverse inter-modulations among...
BACKGROUND
The high prevalence of desynchronized biological rhythms is becoming a primary public health concern. We assess complex and diverse inter-modulations among multi-frequency rhythms present in blood pressure (BP) and heart rate (HR).
SUBJECTS
and Methods: We performed 7-day/24-hour Ambulatory BP Monitoring in 220 (133 women) residents (23 to 74 years) of a rural Japanese town in Kochi Prefecture under everyday life conditions.
RESULTS
A symphony of biological clocks contributes to the preservation of a synchronized circadian system. (1) Citizens with an average 12.02-h period had fewer vascular variability disorders than those with shorter (11.37-h) or longer (12.88-h) periods (P<0.05), suggesting that the circasemidian rhythm is potentially important for human health. (2) An appropriate BP-HR coupling promoted healthier circadian profiles than a phase-advanced BP: lower 7-day nighttime SBP (106.8 vs. 112.9 mmHg, P=0.0469), deeper nocturnal SBP dip (20.5% vs. 16.8%, P=0.0101), and less frequent incidence of masked non-dipping (0.53 vs. 0.86, P=0.0378), identifying the night as an important time window.
CONCLUSION
Adaptation to irregular schedules in everyday life occurs unconsciously at night, probably initiated from the brain default mode network, in coordination with the biological clock system, including a reinforced about 12-hour clock, as "a biological clock-guided core integration system".
PubMed: 38906327
DOI: 10.1016/j.bj.2024.100753 -
Cancers May 2024This study aimed to predict stress in patients using artificial intelligence (AI) from biological signals and verify the effect of stress on respiratory irregularity. We...
This study aimed to predict stress in patients using artificial intelligence (AI) from biological signals and verify the effect of stress on respiratory irregularity. We measured 123 cases in 41 patients and calculated stress scores with seven stress-related features derived from heart-rate variability. The distribution and trends of stress scores across the treatment period were analyzed. Before-treatment information was used to predict the stress features during treatment. AI models included both non-pretrained (decision tree, random forest, support vector machine, long short-term memory (LSTM), and transformer) and pretrained (ChatGPT) models. Performance was evaluated using 10-fold cross-validation, exact match ratio, accuracy, recall, precision, and F1 score. Respiratory irregularities were calculated in phase and amplitude and analyzed for correlation with stress score. Over 90% of the patients experienced stress during radiation therapy. LSTM and prompt engineering GPT4.0 had the highest accuracy (feature classification, LSTM: 0.703, GPT4.0: 0.659; stress classification, LSTM: 0.846, GPT4.0: 0.769). A 10% increase in stress score was associated with a 0.286 higher phase irregularity ( < 0.025). Our research pioneers the use of AI and biological signals for stress prediction in patients undergoing radiation therapy, potentially identifying those needing psychological support and suggesting methods to improve radiotherapy effectiveness through stress management.
PubMed: 38893087
DOI: 10.3390/cancers16111964 -
Reviews on Environmental Health Jun 2024The fifth generation, 5G, for wireless communication is currently deployed in Sweden since 2019/2020, as well as in many other countries. We have previously published... (Review)
Review
The fifth generation, 5G, for wireless communication is currently deployed in Sweden since 2019/2020, as well as in many other countries. We have previously published seven case reports that include a total of 16 persons aged between 4 and 83 years that developed the microwave syndrome within short time after being exposed to 5G base stations close to their dwellings. In all cases high radiofrequency (RF) radiation from 4G/5G was measured with a broadband meter. RF radiation reached >2,500,000 to >3,180,000 μW/m in peak maximum value in three of the studies. In total 41 different health issues were assessed for each person graded 0 (no complaint) to 10 (worst symptoms). Most prevalent and severe were sleeping difficultly (insomnia, waking night time, early wake-up), headache, fatique, irritability, concentration problems, loss of immediate memory, emotional distress, depression tendency, anxiety/panic, dysesthesia (unusual touched based sensations), burning and lancinating skin, cardiovascular symptoms (transitory high or irregular pulse), dyspnea, and pain in muscles and joints. Balance disorder and tinnitus were less prevalent. All these symptoms are included in the microwave syndrome. In most cases the symptoms declined and disappeared within a short time period after the studied persons had moved to a place with no 5G. These case histories are classical examples of provocation studies. They reinforce the urgency to inhibit the deployment of 5G until more safety studies have been performed.
PubMed: 38889394
DOI: 10.1515/reveh-2024-0017 -
Heliyon Jun 2024Horses participating in endurance events encounter enormous physical challenges. Heart rate (HR) and heart rate variability (HRV) have been reported before and after...
Horses participating in endurance events encounter enormous physical challenges. Heart rate (HR) and heart rate variability (HRV) have been reported before and after endurance rides, but these have not been determined during the rides. Moreover, the modulation in HRV and haematology in horses with different ride results (completed a course or disqualified due to irregular gait) have not been elucidated. Therefore, this study aimed to investigate changes in HR, HRV, and haematological parameters during novice endurance rides and to compare these parameters between horses that successfully completed the course (SC) or were disqualified for irregular gait (FTQ-GA). Beat-to-beat (RR) intervals of 16 healthy horses (aged 6-14 years) were recorded before and throughout the approximately 40 km endurance event. Blood samples were taken at the pre-ride inspection and after passing each veterinary inspection. HRV and haematology measures were determined from nine SC and seven FTQ-GA horses. Horses with different ride results demonstrated distinctive physiological stress responses. Increases in PCV, RBC, WBC and neutrophils after completing the ride were found only in SC horses, implying that they were ridden with greater effort than FTQ-GA horses. A reduction in HRV during warm-up, followed by a significant reduction during the first and second riding phases, was observed. HRV returned to baseline at the compulsory rest period of both phases. FTQ-GA horses experienced lower RR intervals, RR triangular index, modified deceleration capacity, very-low-frequency band, and parasympathetic nervous system index, coinciding with higher HR and sympathetic nervous system and stress indices than SC horses. These results indicated that endurance horses revealed a shift toward sympathetic activity during the ride. Lower parasympathetic activity in FTQ-GA horses suggests they were under more stress or discomfort than SC horses in novice endurance rides. These results have welfare implications, indicating the need for additional rest breaks in FTQ-GA horses.
PubMed: 38845925
DOI: 10.1016/j.heliyon.2024.e31874 -
Heliyon May 2024Postoperative atrial fibrillation (POAF) is considered the most prevalent irregular heart rhythm after heart surgery. The cardiac autonomic nervous system significantly...
BACKGROUND AND AIMS
Postoperative atrial fibrillation (POAF) is considered the most prevalent irregular heart rhythm after heart surgery. The cardiac autonomic nervous system significantly affects POAF, and neuropeptide Y (NPY), an abundant neuropeptide in the cardiovascular system, is involved in this autonomic regulation. The current work aimed to examine the potential association of NPY with POAF in individuals administered isolated off-pump coronary artery bypass grafting.
METHODS
From January 1 to May 31, 2020, we examined consecutive cases administered successful isolated off-pump coronary artery bypass grafting with no previously diagnosed atrial fibrillation (AF). Clinical characteristics and plasma samples were collected before surgery. NPY was quantified by enzyme-linked immunosorbent assay (ELISA) in peripheral blood, and POAF cases were identified through a 7-day Holter monitoring.
RESULTS
Among 120 cases with no previously diagnosed AF, 33 (27.5 %) developed POAF during hospitalization. Median NPY levels were markedly elevated in the POAF group in comparison with the sinus rhythm group (31.72 vs. 27.95, P = 0.014). Multivariable logistic regression analysis revealed age (OR = 1.135, 95%CI 1.054-1.223; P = 0.001), left atrial size (OR = 1.136, 95%CI 1.004-1.285; P = 0.043), and NPY levels in peripheral blood (OR = 1.055, 95%CI 1.002-1.111; p = 0.041) independently predicted POAF. Additionally, NPY levels were positively correlated with high-frequency (HF) (r = 0.2774, P = 0.0022) and low-frequency (LF) (r = 0.2095, P = 0.0217) components of heart rate variability.
CONCLUSION
In summary, this study demonstrates an association between elevated NPY levels in peripheral blood before surgery and POAF occurrence.
PubMed: 38803941
DOI: 10.1016/j.heliyon.2024.e31251 -
Nature Communications May 2024The conformational dynamics of nucleosome arrays generate a diverse spectrum of microscopic states, posing challenges to their structural determination. Leveraging...
The conformational dynamics of nucleosome arrays generate a diverse spectrum of microscopic states, posing challenges to their structural determination. Leveraging cryogenic electron tomography (cryo-ET), we determine the three-dimensional (3D) structures of individual mononucleosomes and arrays comprising di-, tri-, and tetranucleosomes. By slowing the rate of condensation through a reduction in ionic strength, we probe the intra-array structural transitions that precede inter-array interactions and liquid droplet formation. Under these conditions, the arrays exhibite irregular zig-zag conformations with loose packing. Increasing the ionic strength promoted intra-array compaction, yet we do not observe the previously reported regular 30-nanometer fibers. Interestingly, the presence of H1 do not induce array compaction; instead, one-third of the arrays display nucleosomes invaded by foreign DNA, suggesting an alternative role for H1 in chromatin network construction. We also find that the crucial parameter determining the structure adopted by chromatin arrays is the angle between the entry and exit of the DNA and the corresponding tangents to the nucleosomal disc. Our results provide insights into the initial stages of intra-array compaction, a critical precursor to condensation in the regulation of chromatin organization.
Topics: Nucleosomes; Electron Microscope Tomography; DNA; Cryoelectron Microscopy; Nucleic Acid Conformation; Chromatin; Histones; Osmolar Concentration; Animals
PubMed: 38782894
DOI: 10.1038/s41467-024-48305-1 -
Aquatic Toxicology (Amsterdam,... Jun 2024Ammonia is a respiratory gas that is produced during the process of protein deamination. In the unionised form (NH), it readily crosses biological membranes and is...
Ammonia is a respiratory gas that is produced during the process of protein deamination. In the unionised form (NH), it readily crosses biological membranes and is highly toxic to fish. In the present study we examined the effects of unionized ammonia (UIA), on the resting oxygen consumption (MO), ventilation frequency (f), heart rate (HR) and heart rate variability (HRV) in Nile tilapia (Oreochromis niloticus). Fish were either exposed to progressively increasing UIA concentrations, up to 97 µM over a 5 h period, or to a constant UIA level of 7 µM over a 24 h period. For both treatment groups resting MO, HR and f were recorded as physiological variables. Relative to the control group, the fish groups exposed to the incremental UIA levels did not exhibit significant changes in their MO, HR and f at UIA concentrations of 4, 10, 35, or 61 µM compared to control fish. Exposure to 97 µM UIA, however, elicited abrupt and significant downregulations (p < 0.05) in all three responses, as MO, HR and fv decreased by 25, 54 and 76 % respectively, compared to control measurements. Heart rate became increasingly irregular with increasing UIA concentrations, and heart rate variability was significantly increased at 61 and 97 µM UIA. Prolonged exposure elicited significant changes at exposure 7 µM UIA. Standard (SMR) and maximum metabolic rate (MMR) were significantly reduced, as was the corresponding f and HR. It is evident from this study that Nile tilapia is tolerant to short term exposure to UIA up to 61 µM but experience a significant metabolic change under conditions of prolonged UIA exposures even at low concentrations.
Topics: Animals; Ammonia; Heart Rate; Cichlids; Water Pollutants, Chemical; Oxygen Consumption
PubMed: 38692129
DOI: 10.1016/j.aquatox.2024.106932 -
Cureus Mar 2024Cardiac autonomic neuropathy (CAN) is a disorder affecting the autonomic nerves that regulate the cardiovascular system, leading to irregular heart rate and blood...
INTRODUCTION
Cardiac autonomic neuropathy (CAN) is a disorder affecting the autonomic nerves that regulate the cardiovascular system, leading to irregular heart rate and blood pressure control. It is commonly associated with diabetes mellitus but can also result from other conditions such as autoimmune disorders, chronic kidney disease, alcohol abuse, and certain medications. Screening for CAN is essential, particularly in individuals with poor glycemic control, cardiovascular risk factors, or complications. Early identification of CAN is vital for timely intervention to prevent or manage cardiovascular complications effectively. Regular screening helps detect CAN before symptoms emerge, enabling early intervention to slow or halt its progression. This study examined the relationship between sudomotor function and cardiovascular reflex tests.
MATERIAL AND METHODS
This was a cross-sectional study conducted between June 2019 and June 2020. The study included 271 subjects aged 18 years and above who provided informed consent, were diagnosed with type 2 diabetes mellitus (T2DM), and were overweight or obese. Exclusion criteria encompassed patients with other types of diabetes, pregnant women, those with recent neoplasm diagnoses, stroke sequelae, history of myocardial infarction, or pelvic limb amputations. The assessment of cardiac autonomic neuropathy involved conducting an electrocardiogram and evaluating the QTc interval in the morning before taking medication. Additionally, cardiovascular reflex tests (CART) were conducted, including assessments of heart rate variability during deep breathing, the Valsalva maneuver, and changes in orthostatic position. Simultaneously, the diagnosis of CAN was assessed by performing a sweat test using a Sudoscan assessment (Impeto Medical, Moulineaux, France). Results: More than half of the participants (52%, n=143) were female. Significant differences in statistical measures were noted between females and males regarding age, systolic blood pressure, fasting blood glucose, A1c level, total cholesterol, triglycerides, gamma-glutamyl transferase, and bilirubin levels. Within the CAN-diagnosed group (CAN+), 40.92% were classified as mild cases (n=90), 47.27% as moderate cases (n=104), and 11.81% as severe cases (n=26). Among the CAN+ group, 54% (n=119) were women. Electrochemical skin conductance was lower in the CAN+ group than the CAN- group in hands (67.34±15.51 μS versus 72.38±12.12 μS, p=0.008) and feet (73.37±13.38 μS versus 82.84 ±10.29 μS, p<0.001). The Sudoscan-CAN score significantly correlated with Ewing scores (r= 0.522, p<0.001). In multiple linear regression analysis, the Sudoscan-CAN score remained significantly associated with age, high BMI, long-standing diabetes, and Ewing score.
CONCLUSIONS
Sudoscan demonstrates potential in identifying patients with an increased risk of CAN. Its integration into clinical practice can improve patient outcomes through early detection, risk stratification, and personalized treatment approaches. Its non-invasive, portable, and user-friendly features render it suitable for utilization in outreach programs or resource-constrained settings as part of screening efforts designed to pinpoint high-risk individuals for additional assessment.
PubMed: 38686272
DOI: 10.7759/cureus.57226