Search results for: beating heart CABG
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1166

Search results for: beating heart CABG

956 A Hybrid Multi-Pole Fe₇₈Si₁₃B₉+FeSi₃ Soft Magnetic Core for Application in the Stators of the Low-Power Permanent Magnet Brushless Direct Current Motors

Authors: P. Zackiewicz, M. Hreczka, R. Kolano, A. Kolano-Burian

Abstract:

New types of materials applied as the stators in the Permanent Magnet Brushless Direct Current motors used in the heart supporting pumps are presented. The main focus of this work is the research on the fabrication of a hybrid nine-pole soft magnetic core consisting of a soft magnetic carrier ring with rectangular notches, made from the FeSi3 strip, and nine soft magnetic poles. This soft magnetic core is made in three stages: (a) preparation of the carrier rings from soft magnetic material with the lowest possible power losses and suitable stiffness, (b) preparation of trapezoidal soft magnetic poles from Metglas 2605 SA1 type ribbons, and (c) making durable connection between the poles and the carrier ring, capable of withstanding a four-times greater tearing force than that present during normal operation of the motor pump. All magnetic properties measurements were made using Remacomp C-1200 (Magnet Physik, Germany) and 450 Gaussometer (Lake Shore, USA) and the electrical characteristics were measured using laboratory generator DF1723009TC (NDN, Poland). Specific measurement techniques used to determine properties of the hybrid cores were presented. Obtained results allow developing the fabrication technology with an account of the intended application of these cores in the stators of the low-power PMBLDC motors used in implanted heart operation supporting pumps. The proposed measurement methodology is appropriate for assessing the quality of the stators.

Keywords: amorphous materials, heart supporting pump, PMBLDC motor, soft magnetic materials

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955 Assessment of Five Photoplethysmographic Methods for Estimating Heart Rate Variability

Authors: Akshay B. Pawar, Rohit Y. Parasnis

Abstract:

Heart Rate Variability (HRV) is a widely used indicator of the regulation between the autonomic nervous system (ANS) and the cardiovascular system. Besides being non-invasive, it also has the potential to predict mortality in cases involving critical injuries. The gold standard method for determining HRV is based on the analysis of RR interval time series extracted from ECG signals. However, because it is much more convenient to obtain photoplethysmogramic (PPG) signals as compared to ECG signals (which require the attachment of several electrodes to the body), many researchers have used pulse cycle intervals instead of RR intervals to estimate HRV. They have also compared this method with the gold standard technique. Though most of their observations indicate a strong correlation between the two methods, recent studies show that in healthy subjects, except for a few parameters, the pulse-based method cannot be a surrogate for the standard RR interval- based method. Moreover, the former tends to overestimate short-term variability in heart rate. This calls for improvements in or alternatives to the pulse-cycle interval method. In this study, besides the systolic peak-peak interval method (PP method) that has been studied several times, four recent PPG-based techniques, namely the first derivative peak-peak interval method (P1D method), the second derivative peak-peak interval method (P2D method), the valley-valley interval method (VV method) and the tangent-intersection interval method (TI method) were compared with the gold standard technique. ECG and PPG signals were obtained from 10 young and healthy adults (consisting of both males and females) seated in the armchair position. In order to de-noise these signals and eliminate baseline drift, they were passed through certain digital filters. After filtering, the following HRV parameters were computed from PPG using each of the five methods and also from ECG using the gold standard method: time domain parameters (SDNN, pNN50 and RMSSD), frequency domain parameters (Very low-frequency power (VLF), Low-frequency power (LF), High-frequency power (HF) and Total power or “TP”). Besides, Poincaré plots were also plotted and their SD1/SD2 ratios determined. The resulting sets of parameters were compared with those yielded by the standard method using measures of statistical correlation (correlation coefficient) as well as statistical agreement (Bland-Altman plots). From the viewpoint of correlation, our results show that the best PPG-based methods for the determination of most parameters and Poincaré plots are the P2D method (shows more than 93% correlation with the standard method) and the PP method (mean correlation: 88%) whereas the TI, VV and P1D methods perform poorly (<70% correlation in most cases). However, our evaluation of statistical agreement using Bland-Altman plots shows that none of the five techniques agrees satisfactorily well with the gold standard method as far as time-domain parameters are concerned. In conclusion, excellent statistical correlation implies that certain PPG-based methods provide a good amount of information on the pattern of heart rate variation, whereas poor statistical agreement implies that PPG cannot completely replace ECG in the determination of HRV.

Keywords: photoplethysmography, heart rate variability, correlation coefficient, Bland-Altman plot

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954 Relatively High Heart-Rate Variability Predicts Greater Survival Chances in Patients with Covid-19

Authors: Yori Gidron, Maartje Mol, Norbert Foudraine, Frits Van Osch, Joop Van Den Bergh, Moshe Farchi, Maud Straus

Abstract:

Background: The worldwide pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-COV2), which began in 2019, also known as Covid-19, has infected over 136 million people and tragically took the lives of over 2.9 million people worldwide. Many of the complications and deaths are predicted by the inflammatory “cytokine storm.” One way to progress in the prevention of death is by finding a predictive and protective factor that inhibits inflammation, on the one hand, and which also increases anti-viral immunity on the other hand. The vagal nerve does precisely both actions. This study examined whether vagal nerve activity, indexed by heart-rate variability (HRV), predicts survival in patients with Covid-19. Method: We performed a pseudo-prospective study, where we retroactively obtained ECGs of 271 Covid-19 patients arriving at a large regional hospital in The Netherlands. HRV was indexed by the standard deviation of the intervals between normal heartbeats (SDNN). We examined patients’ survival at 3 weeks and took into account multiple confounders and known prognostic factors (e.g., age, heart disease, diabetes, hypertension). Results: Patients’ mean age was 68 (range: 25-95) and nearly 22% of the patients had died by 3 weeks. Their mean SDNN (17.47msec) was far below the norm (50msec). Importantly, relatively higher HRV significantly predicted a higher chance of survival, after statistically controlling for patients’ age, cardiac diseases, hypertension and diabetes (relative risk, H.R, and 95% confidence interval (95%CI): H.R = 0.49, 95%CI: 0.26 – 0.95, p < 0.05). However, since HRV declines rapidly with age and since age is a profound predictor in Covid-19, we split the sample by median age (40). Subsequently, we found that higher HRV significantly predicted greater survival in patients older than 70 (H.R = 0.35, 95%CI: 0.16 – 0.78, p = 0.01), but HRV did not predict survival in patients below age 70 years (H.R = 1.11, 95%CI: 0.37 – 3.28, p > 0.05). Conclusions: To the best of our knowledge, this is the first study showing that higher vagal nerve activity, as indexed by HRV, is an independent predictor of higher chances for survival in Covid-19. The results are in line with the protective role of the vagal nerve in diseases and extend this to a severe infectious illness. Studies should replicate these findings and then test in controlled trials whether activating the vagus nerve may prevent mortality in Covid-19.

Keywords: Covid-19, heart-rate Variability, prognosis, survival, vagal nerve

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953 Fast and Non-Invasive Patient-Specific Optimization of Left Ventricle Assist Device Implantation

Authors: Huidan Yu, Anurag Deb, Rou Chen, I-Wen Wang

Abstract:

The use of left ventricle assist devices (LVADs) in patients with heart failure has been a proven and effective therapy for patients with severe end-stage heart failure. Due to the limited availability of suitable donor hearts, LVADs will probably become the alternative solution for patient with heart failure in the near future. While the LVAD is being continuously improved toward enhanced performance, increased device durability, reduced size, a better understanding of implantation management becomes critical in order to achieve better long-term blood supplies and less post-surgical complications such as thrombi generation. Important issues related to the LVAD implantation include the location of outflow grafting (OG), the angle of the OG, the combination between LVAD and native heart pumping, uniform or pulsatile flow at OG, etc. We have hypothesized that an optimal implantation of LVAD is patient specific. To test this hypothesis, we employ a novel in-house computational modeling technique, named InVascular, to conduct a systematic evaluation of cardiac output at aortic arch together with other pertinent hemodynamic quantities for each patient under various implantation scenarios aiming to get an optimal implantation strategy. InVacular is a powerful computational modeling technique that integrates unified mesoscale modeling for both image segmentation and fluid dynamics with the cutting-edge GPU parallel computing. It first segments the aortic artery from patient’s CT image, then seamlessly feeds extracted morphology, together with the velocity wave from Echo Ultrasound image of the same patient, to the computation model to quantify 4-D (time+space) velocity and pressure fields. Using one NVIDIA Tesla K40 GPU card, InVascular completes a computation from CT image to 4-D hemodynamics within 30 minutes. Thus it has the great potential to conduct massive numerical simulation and analysis. The systematic evaluation for one patient includes three OG anastomosis (ascending aorta, descending thoracic aorta, and subclavian artery), three combinations of LVAD and native heart pumping (1:1, 1:2, and 1:3), three angles of OG anastomosis (inclined upward, perpendicular, and inclined downward), and two LVAD inflow conditions (uniform and pulsatile). The optimal LVAD implantation is suggested through a comprehensive analysis of the cardiac output and related hemodynamics from the simulations over the fifty-four scenarios. To confirm the hypothesis, 5 random patient cases will be evaluated.

Keywords: graphic processing unit (GPU) parallel computing, left ventricle assist device (LVAD), lumped-parameter model, patient-specific computational hemodynamics

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952 Quantitative Evaluation of Mitral Regurgitation by Using Color Doppler Ultrasound

Authors: Shang-Yu Chiang, Yu-Shan Tsai, Shih-Hsien Sung, Chung-Ming Lo

Abstract:

Mitral regurgitation (MR) is a heart disorder which the mitral valve does not close properly when the heart pumps out blood. MR is the most common form of valvular heart disease in the adult population. The diagnostic echocardiographic finding of MR is straightforward due to the well-known clinical evidence. In the determination of MR severity, quantification of sonographic findings would be useful for clinical decision making. Clinically, the vena contracta is a standard for MR evaluation. Vena contracta is the point in a blood stream where the diameter of the stream is the least, and the velocity is the maximum. The quantification of vena contracta, i.e. the vena contracta width (VCW) at mitral valve, can be a numeric measurement for severity assessment. However, manually delineating the VCW may not accurate enough. The result highly depends on the operator experience. Therefore, this study proposed an automatic method to quantify VCW to evaluate MR severity. Based on color Doppler ultrasound, VCW can be observed from the blood flows to the probe as the appearance of red or yellow area. The corresponding brightness represents the value of the flow rate. In the experiment, colors were firstly transformed into HSV (hue, saturation and value) to be closely align with the way human vision perceives red and yellow. Using ellipse to fit the high flow rate area in left atrium, the angle between the mitral valve and the ultrasound probe was calculated to get the vertical shortest diameter as the VCW. Taking the manual measurement as the standard, the method achieved only 0.02 (0.38 vs. 0.36) to 0.03 (0.42 vs. 0.45) cm differences. The result showed that the proposed automatic VCW extraction can be efficient and accurate for clinical use. The process also has the potential to reduce intra- or inter-observer variability at measuring subtle distances.

Keywords: mitral regurgitation, vena contracta, color doppler, image processing

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951 The Amount of Organic Phosphates (Like DPG) Existing in Blood is Determining Factor of Mammal’s Bulk

Authors: Ramin Amirmardfar

Abstract:

Throughout Necessary oxygen should be supplied for all cells of a mammal at any moment through blood to make it possible remain alive all cells the mammal’s body. In case a mammal’s bulk is large, there is a farther distance between cells in different tissues and mammals’ heart. Therefore red blood cells in bulky mammal’s body should be capable of conveying oxygen to farther distances. To make it practical, oxygen should be glued red blood cells tenaciously. In other words, cohesion strength of oxygen to red blood cell of bulky mammal’s blood should be much more than the same of small mammal’s blood. In mammal’s bodies, the controlling factor of amount of cohesion of oxygen to red blood cell, are organic phosphates (like DPG). The less DPG in red blood cells of a mammal, the more cohesion of oxygen to red blood cell (at the same rate). As much as oxygen is glued more tenacious to red blood cells, oxygen could been carried to farther distance and as much as oxygen could be conveyed to farther points of heart, bulk of mammal could be larger at the same rate.

Keywords: mammals size, animals size, organic phosphates, DPG, red blood cell, metabolism

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950 Protective Effect of Vitamin D on Cardiac Apoptosis in Obese Rats

Authors: Kadeejah Alsolami, Zainab Alrefay, Husaam Awad

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Obesity and vitamin D deficiency have both been related to cardiovascular disease. The present work aimed to investigate the possible protective effect of vitamin D on cardiac apoptosis in a rat model of dietary-induced obesity. Methods: 30 male Wistar rats included in this study. They were allocated into 4 groups: Control (n=5), animal were fed standard diet for 3 months: Control + vitamin D (VD) (n=5),animals were fed a standard diet with 400IU VD/kg for 3 months: hypercaloric diets group (n=10), animals were fed a high fat diet for 3 months: hypercaloric diet with VD group (n=10), animals were fed a high fat diet with 400IU VD/kg for 3 months. At the beginning of the experiment, the weight and length were measured to assess body mass index (BMI) and repeated every 45 days. Food intake and body weight were monitored throughout the study period. Then rats were sacrificed and heart tissues collected for Quantitative Real-time polymerase chain reaction (qRT-PCR). qRT-PCR used to detect different genetic markers of apoptosis (anti-apoptotic gene (BCL2), a pro-apoptotic gene(BAX), pro-apoptotic genes (FAS, FAS-L), tumour necrosis factor (TNF), mitogen-activated protein kinases (MAPK). Results: FAS and FAS-L gene expression were significantly upregulated in rats fed with high fat diet. And FAS-L gene expression was significantly upregulated in all groups on comparison with control. Whereas Bax gene expression was significantly downregulated in rats fed with high-fat diet supplied with vitamin D. TNF was significantly upregulated in rats fed with high-fat diet treated with vitamin D. MAPK was significantly upregulated in rats fed with high fat diet group, and in rats fed with high-fat diet supplied with vitamin D. Conclusion: The cardiac apoptotic pathways were more activated in rats fed with high-fat than lean rats. And vitamin D protect the heart from the cardiac mitochondrial-dependent apoptotic pathway.

Keywords: apoptosis, heart, obesity, Vitamin D

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949 Hydrogen Sulfide Releasing Ibuprofen Derivative Can Protect Heart After Ischemia-Reperfusion

Authors: Virag Vass, Ilona Bereczki, Erzsebet Szabo, Nora Debreczeni, Aniko Borbas, Pal Herczegh, Arpad Tosaki

Abstract:

Hydrogen sulfide (H₂S) is a toxic gas, but it is produced by certain tissues in a small quantity. According to earlier studies, ibuprofen and H₂S has a protective effect against damaging heart tissue caused by ischemia-reperfusion. Recently, we have been investigating the effect of a new water-soluble H₂S releasing ibuprofen molecule administered after artificially generated ischemia-reperfusion on isolated rat hearts. The H₂S releasing property of the new ibuprofen derivative was investigated in vitro in medium derived from heart endothelial cell isolation at two concentrations. The ex vivo examinations were carried out on rat hearts. Rats were anesthetized with an intraperitoneal injection of ketamine, xylazine, and heparin. After thoracotomy, hearts were excised and placed into ice-cold perfusion buffer. Perfusion of hearts was conducted in Langendorff mode via the cannulated aorta. In our experiments, we studied the dose-effect of the H₂S releasing molecule in Langendorff-perfused hearts with the application of gradually increasing concentration of the compound (0- 20 µM). The H₂S releasing ibuprofen derivative was applied before the ischemia for 10 minutes. H₂S concentration was measured with an H₂S detecting electrochemical sensor from the coronary effluent solution. The 10 µM concentration was chosen for further experiments when the treatment with this solution was occurred after the ischemia. The release of H₂S is occurred by the hydrolyzing enzymes that are present in the heart endothelial cells. The protective effect of the new H₂S releasing ibuprofen molecule can be confirmed by the infarct sizes of hearts using the Triphenyl-tetrazolium chloride (TTC) staining method. Furthermore, we aimed to define the effect of the H₂S releasing ibuprofen derivative on autophagic and apoptotic processes in damaged hearts after investigating the molecular markers of these events by western blotting and immunohistochemistry techniques. Our further studies will include the examination of LC3I/II, p62, Beclin1, caspase-3, and other apoptotic molecules. We hope that confirming the protective effect of new H₂S releasing ibuprofen molecule will open a new possibility for the development of more effective cardioprotective agents with exerting fewer side effects. Acknowledgment: This study was supported by the grants of NKFIH- K-124719 and the European Union and the State of Hungary co- financed by the European Social Fund in the framework of GINOP- 2.3.2-15-2016-00043.

Keywords: autophagy, hydrogen sulfide, ibuprofen, ischemia, reperfusion

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948 Developing and Evaluating Clinical Risk Prediction Models for Coronary Artery Bypass Graft Surgery

Authors: Mohammadreza Mohebbi, Masoumeh Sanagou

Abstract:

The ability to predict clinical outcomes is of great importance to physicians and clinicians. A number of different methods have been used in an effort to accurately predict these outcomes. These methods include the development of scoring systems based on multivariate statistical modelling, and models involving the use of classification and regression trees. The process usually consists of two consecutive phases, namely model development and external validation. The model development phase consists of building a multivariate model and evaluating its predictive performance by examining calibration and discrimination, and internal validation. External validation tests the predictive performance of a model by assessing its calibration and discrimination in different but plausibly related patients. A motivate example focuses on prediction modeling using a sample of patients undergone coronary artery bypass graft (CABG) has been used for illustrative purpose and a set of primary considerations for evaluating prediction model studies using specific quality indicators as criteria to help stakeholders evaluate the quality of a prediction model study has been proposed.

Keywords: clinical prediction models, clinical decision rule, prognosis, external validation, model calibration, biostatistics

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947 Effect of Cardio-Specific Overexpression of MUL1, a Mitochondrial Protein on Myocardial Function

Authors: Ximena Calle, Plinio Cantero-López, Felipe Muñoz-Córdova, Mayarling-Francisca Troncoso, Sergio Lavandero, Valentina Parra

Abstract:

MUL1, a mitochondrial E3 ubiquitin ligase anchored to the outer mitochondrial membrane, is highly expressed in the heart. MUL1 is involved in multiple biological pathways associated with mitochondrial dynamics. Increased MUL1 affects the balance between fission and fusion, affecting mitochondrial function, which plays a crucial role in myocardial function. Therefore, it is interesting to evaluate the effect of cardiac-specific overexpression of MUL1 on myocardial function. Aim: To determine heart functionality in a mouse model with cardio-specific overexpression MUL1 protein. Methods and Results: Male C57BL/Tg transgenic mice with cardiomyocyte-specific overexpression of MUL1 (n=10) and control (n=4) were evaluated at 12, 27, and 35 weeks of age. Glucose tolerance curve determination was performed after a 6-hours fast to assess metabolic capacity, treadmill test, and systolic, and diastolic pressure was evaluated by the mouse tail-cuff blood pressure system equipment. The result showed no glucose tolerance curve, and the treadmill test demonstrated no significant changes between groups. However, substantial changes in diastolic function were observed by ultrasound and determination of cardiac hypertrophy proteins by western blot. Conclusions: Cardio-specific overexpression of MUL1 in mice without any treatment affects diastolic cardiac function, thus showing the important role contributed by MUL1 in the heart. Future research should evaluate the effect of cardiomyocyte-specific overexpression of MUL1 in pathological conditions such as a high-fat diet is one of the main risk factors for cardiovascular disease.

Keywords: diastolic dysfunction, hypertrophy cardiac, mitochondrial E3 ubiquitin ligase 1, MUL1

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946 Comparison of Cardiomyogenic Potential of Amniotic Fluid Mesenchymal Stromal Cells Derived from Normal and Isolated Congenital Heart Defective Fetuses

Authors: Manali Jain, Neeta Singh, Raunaq Fatima, Soniya Nityanand, Mandakini Pradhan, Chandra Prakash Chaturvedi

Abstract:

Isolated Congenital Heart Defect (ICHD) is the major cause of neonatal death worldwide among all forms of CHDs. A significant proportion of fetuses with ICHD die in the neonatal period if no treatment is provided. Recently, stem cell therapies have emerged as a potential approach to ameliorate ICHD in children. ICHD is characterized by cardiac structural abnormalities during embryogenesis due to alterations in the cardiomyogenic properties of a pool of cardiac progenitors/ stem cells associated with fetal heart development. The stem cells present in the amniotic fluid (AF) are of fetal origin and may reflect the physiological and pathological changes in the fetus during embryogenesis. Therefore, in the present study, the cardiomyogenic potential of AF-MSCs derived from fetuses with ICHD (ICHD AF-MSCs) has been evaluated and compared with that of AF-MSCs of structurally normal fetuses (normal AF-MSCs). Normal and ICHD AF-MSC were analyzed for the expression of cardiac progenitor markers viz., stage-specific embryonic antigen-1 (SSEA-1), vascular endothelial growth factor 2 (VEGFR-2) and platelet-derived growth factor receptor-alpha (PDGFR-α) by flow cytometry. The immunophenotypic characterization revealed that ICHD AF-MSCs have significantly lower expression of cardiac progenitor markers VEGFR-2 (0.14% ± 0.6 vs.48.80% ± 0.9; p <0.01), SSEA-1 (70.86% ± 2.4 vs. 88.36% ±2.7; p <0.01), and PDGFR-α (3.92% ± 1.8 vs. 47.59% ± 3.09; p <0.01) in comparison to normal AF-MSCs. Upon induction with 5’-azacytidine for 21 days, ICHD AF-MSCs showed a significantly down-regulated expression of cardiac transcription factors such as GATA-4 (0.4 ± 0.1 vs. 6.8 ± 1.2; p<0.01), ISL-1 (2.3± 0.6 vs. 14.3 ± 1.12; p<0.01), NK-x 2-5 (1.1 ± 0.3 vs. 14.1 ±2.8; p<0.01), TBX-5 (0.4 ± 0.07 vs. 4.4 ± 0.3; p<0.001), and TBX-18 (1.3 ± 0.2 vs. 4.19 ± 0.3; p<0.01) when compared with the normal AF-MSCs. Furthermore, immunocytochemical staining revealed that both types of AF-MSCs could differentiate into cardiovascular lineages and express cardiomyogenic, endothelial, and smooth muscle actin markers, viz., cardiac troponin (cTNT), CD31, and alpha-smooth muscle actin (α-SMA). However, normal AF-MSCs showed an enhanced expression of cTNT (p<0.001), CD31 (p<0.01), and α-SMA (p<0.05), compared to ICHD AF-MSCs. Overall, these results suggest that the ICHD-AF-MSCs have a defective cardiomyogenic differentiation potential and that the defects in these stem cells may have a role in the pathogenesis of ICHD.

Keywords: amniotic fluid, cardiomyogenic potential, isolated congenital heart defect, mesenchymal stem cells

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945 Information Communication Technology in Early Childhood Education: An Assessment of the Quality of ICT in the New Mega Primary Schools in Ondo State, Southwestern Nigeria

Authors: Oluyemi Christianah Ojo

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This study seeks to investigate the quality of ICT provided in the new Caring Heart schools in Ondo State, Nigeria. The population for the study was all caring Heart Mega Schools in Ondo State, Nigeria. Research questions were generated; two instruments CCCMS and TQCUC were used to elicit information from the schools and the teachers. The study adopts descriptive survey approach. The studies revealed and concluded that ICT components were available and adequate in these schools, Charts showing ICT components and other forms of computer devices used as instructional materials were available but were not adequate; teachers teaching computer studies are competent in the delivery of instructions and in handling computer gadgets in the laboratory. The study recommended the provision of steady electricity, uninterrupted internet facilities and provision of adequate ICT components and charts for effective teaching delivery and learning.

Keywords: facilities, information communication technology, mega primary school, primary education

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944 Considerations for the Use of High Intensity Interval Training in Secondary Physical Education

Authors: Amy Stringer, Resa Chandler

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High Intensity Interval Training (HIIT) involves a 3-10-minute circuit of various exercises which is a viable alternative to a traditional cardiovascular and strength training regimen. Research suggests that measures of health-related fitness can either be maintained or actually improve with the use of this training method. After conducting a 6-week HIIT research study with 10-14 year old children, considerations for using a daily HIIT workout are presented. Is the use of HIIT with children a reasonable consideration for physical education programs? The benefits and challenges of this type of an intervention are identified. This study is significant in that achieving fitness gains in a small amount of daily class time is an attractive concept – especially for physical education teachers who often do not have the time necessary to accomplish all of their curricular goals in the amount of class time assigned. Basic methodologies include students participating in a circuit of exercises for 7-10 minutes at 80-95% of max heart rate as measured by heart rate monitors. Student pre and post fitness test data were collected for cardio-vascular endurance, muscular endurance, and body composition. Research notes as well as commentary by the teachers and researchers who participated in the HIIT study contributed to the understanding of the cost-benefit analysis. Major findings of the study are that HIIT has limited effectiveness but is a good choice for limited class times. Student efficacy of their ability to complete the exercises and visible heart rate data were considered to be significant factors in success of the HIIT study. The effective use of technology promoting positive audience effect during the display of heart rate data was more important at the beginning of the study than at the end. Student ‘buy-in’ and motivation, teacher motivation and ‘buy-in’, the variety of activities in the circuit and the fitness level of the student at the beginning of the study were also findings influencing the fitness outcomes of the study. Concluding Statement: High intensity interval training can be used effectively in a secondary physical education program. It is not a ‘magic bullet’ to produce health-related fitness outcomes in every student but it is an effective tool to enhance student fitness in a limited time and contribute to the goals of the program.

Keywords: cardio vascular fitness, children, high intensity interval training, physical education

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943 Effect of Environmental Changes in Working Heart Rate among Industrial Workers: An Ergonomic Interpretation

Authors: P. Mukhopadhyay, N. C. Dey

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Occupational health hazard is a very common term in every emerging country. Along with the unorganized sector, most organized sectors including government industries are suffering from this affliction. In addition to workload, the seasonal changes also have some impacts on working environment. With this focus in mind, one hundred male industrial workers, who are directly involved to the task of Periodic Overhauling (POH) in a fabricating workshop in the public domain are selected for this research work. They have been studied during work periods throughout different seasons in a year. For each and every season, the participants working heart rate (WHR) is measured and compared with the standards given by different national and internationally recognized agencies i.e., World Health Organization (WHO) and American Conference of Governmental Industrial Hygienists (ACGIH) etc. The different environmental parameters i.e. dry bulb temperature (DBT), wet bulb temperature (WBT), globe temperature (GT), natural wet bulb temperature (NWB), relative humidity (RH), wet bulb globe temperature (WBGT), air velocity (AV), effective temperature (ET) are recorded throughout the seasons to critically observe the effect of seasonal changes on the WHR of the workers. The effect of changes in environment to the WHR of the workers is very much surprising. It is found that the percentages of workers who belong to the ‘very heavy’ workload category are 83.33%, 66.66% and 16.66% in the summer, rainy and winter seasons, respectively. Ongoing undertaking of this type of job profile forces the worker towards occupational disorders causing absenteeism. This occurrence results in lower production rates, and on the other hand, costs due to medical claims also weaken the industry’s economic condition. In this circumstance, the authors are trying to focus on some remedial measures from the ergonomic angle by proposing a new work/ rest regimen and introducing engineering controls along with management controls which may help the worker, and consequently, the management also.

Keywords: workload, working heart rate, occupational health hazard, industrial worker

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942 The Effect of Aerobic Training and Aqueous Extract of C. monogyna (Hawthorn) on Plasma and Heart Angiogenic Mediators in Male Wistar Rats

Authors: Asieh Abbassi Daloii, Ahmad Abdi

Abstract:

Introduction: Sports information suggests that physical inactivity increases the risk of many diseases, including atherosclerosis. Coronary heart disease, stroke and peripheral vascular disease, atherosclerosis and clinical protests. However, exercise can have beneficial effects on risk factors for atherosclerosis by reducing hyperlipidemia, hypertension, obesity, plaque density, increased insulin sensitivity and glucose tolerance is improved. Despite these findings, there is little information about the molecular mechanisms of interaction between the body and its relation to sport and there arteriosclerosis. The present study aims to investigate the effect of six weeks of progressive aerobic training and aqueous extract of crataegus monogyna on vascular endothelial growth factor (VEGF) variations and angiopoetin-1/2 (ANG- 1/2) in plasma and heart tissue in male Wistar rats. Methods: 30 male Wistar rats, 4-6 months old, were randomly divided into four groups: control crataegus monogyna (N=8), training crataegus monogyna (N=8), control saline (N=6), and training saline (N=8). The aerobic training program included running on treadmill at the speed of 34 meters per minute for 60 minutes per day. The training was conducted for six weeks, five days a week. Following each training session, both experimental and control subjects of crataegus monogyna groups were orally fed with 0.5 mg crataegus monogyna extract per gram of the body weight. The normal saline group was given the same amount of the normal saline solution (NS). Eventually, 72 hours after the last training session, blood samples were taken from inferior Verna cava. Conclusion: It is likely that crataegus monogyna extract compared with aerobic training and even combination of both training and crataegus monogyna extract is more effective on angiogenesis.

Keywords: angiopoietin 1, 2, vascular endothelial growth factor, aerobic exercise

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941 Yield Loss in Maize Due to Stem Borers and Their Integrated Management

Authors: C. P. Mallapur, U. K. Hulihalli, D. N. Kambrekar

Abstract:

Maize (Zea mays L.) an important cereal crop in the world has diversified uses including human consumption, animal feed, and industrial uses. A major constraint in low productivity of maize in India is undoubtedly insect pests particularly two species of stem borers, Chilo partellus (Swinhoe) and Sesamia inferens (Walker). The stem borers cause varying level of yield losses in different agro-climate regions (25.7 to 80.4%) resulting in a huge economic loss to the farmers. Although these pests are rather difficult to manage, efforts have been made to combat the menace by using effective insecticides. However, efforts have been made in the present study to integrate various possible approaches for sustainable management of these borers. Two field experiments were conducted separately during 2016-17 at Main Agricultural Research Station, University of Agricultural Sciences, Dharwad, Karnataka, India. In the first experiment, six treatments were randomized in RBD. The insect eggs at pinhead stage (@ 40 eggs/plant) were stapled to the under surface of leaves covering 15-20 % of plants in each plot after 15 days of sowing. The second experiment was planned with nine treatments replicated thrice. The border crop with NB -21 grass was planted all around the plots in the specific treatments while, cowpea intercrop (@6:1-row proportion) was sown along with the main crop and later, the insecticidal spray with chlorantraniliprole and nimbecidine was taken upon need basis in the specific treatments. The results indicated that the leaf injury and dead heart incidence were relatively more in the treatments T₂ and T₄ wherein, no insect control measures were made after the insect release (58.30 & 40.0 % leaf injury and 33.42 and 25.74% dead heart). On the contrary, these treatments recorded higher stem tunneling (32.4 and 24.8%) and resulted in lower grain yield (17.49 and 26.79 q/ha) compared to 29.04, 32.68, 40.93 and 46.38 q/ha recorded in T₁, T₃, T₅ and T₆ treatments, respectively. A maximum yield loss of 28.89 percent was noticed in T₂ followed by 19.59 percent in T₄ where no sprays were imposed. The data on integrated management trial revealed the lowest stem borer damage (19.28% leaf injury and 1.21% dead heart) in T₅ (seed treatment with thiamethoxam 70FS @ 8ml/kg seed + cow intercrop along with nimbecidine 0.03EC @ 5.0 ml/l and chlorantraniliprole 18.5SC spray @ 0.2 ml/l). The next best treatment was T₆ (ST+ NB-21 borer with nimbecidine and chlorantraniliprole spray) with 21.3 and 1.99 percent leaf injury and dead heart incidence, respectively. These treatments resulted in highest grain yield (77.71 and 75.53 q/ha in T₅ and T₆, respectively) compared to the standard check, T₁ (ST+ chlorantraniliprole spray) wherein, 27.63 percent leaf injury and 3.68 percent dead heart were noticed with 60.14 q/ha grain yield. The stem borers can cause yield loss up to 25-30 percent in maize which can be well tackled by seed treatment with thiamethoxam 70FS @ 8ml/kg seed and sowing the crop along with cowpea as intercrop (6:1 row proportion) or NB-21 grass as border crop followed by application of nimbecidine 0.03EC @ 5.0 ml/l and chlorantraniliprole 18.5SC @ 0.2 ml/l on need basis.

Keywords: Maize stem borers, Chilo partellus, Sesamia inferens, crop loss, integrated management

Procedia PDF Downloads 181
940 Noticing Nature: Benefits for Connectedness to Nature and Wellbeing

Authors: Dawn Watling, Lorraine Lecourtois, Adnan Levent, Ryan Jeffries, Aysha Bellamy

Abstract:

Mental health diagnoses are on the rise for adolescents worldwide, with many being unable to access support and increasing use of social prescribing time in nature. There is an increasing need to better understand the preventive benefits of spending time in nature. In this paper, research findings from 599 seven to 12-year-olds completed two sets of questionnaires (before the visit and after a walk in nature). Participants spent time in one of three different biodiverse habitats. Findings explore predictors (including age, sex, and mental health) of increases in connection to nature and well-being. Secondly, research findings from 313 eighteen to 87-year-olds who completed questionnaires and had their heart rate monitored, followed by a self-guided walk, will be discussed. Findings explore predictors (including age, sex, connectedness to nature, well-being, and heart rate as a proxy measure of stress) of increases in mood and feelings of restoration. The discussion will focus on the converging evidence for taking time to notice nature and the role of different environments in enhancing connection to nature, well-being, and positive mental health.

Keywords: nature, connectedness to nature, social prescribing, wellbeing

Procedia PDF Downloads 32
939 Sudden Death of a Cocaine Body Packer: An Autopsy Examination Findings

Authors: Parthasarathi Pramanik

Abstract:

Body packing is a way of transfer drugs across the international border or any drug prohibited area. The drugs are usually hidden in body packets inside the anatomical body cavities like mouth, intestines, rectum, ear, vagina etc. Cocaine is a very common drug for body packing across the world. A 48 year old male was reported dead in his hotel after complaining of chest pain and vomiting. At autopsy, there were eighty-two white cylindrical body packs in the stomach, small and large intestines. Seals of few of the packets were opened. Toxicological examination revealed presence of cocaine in the stomach, liver, kidney and hair samples. Microscopically, presence of myocardial necrosis with interstitial oedema along with hypertrophy and fibrosis of the myocardial fibre suggested heart failure due to cocaine cardio toxicity. However, focal lymphocyte infiltration and perivascular fibrosis in the myocardium also indicated chronic cocaine toxicity of the deceased. After careful autopsy examination it was considered the victim was died due congestive heart failure secondary to acute and chronic cocaine poisoning.

Keywords: cardiac failure, cocaine, body packer, sudden death

Procedia PDF Downloads 320
938 Tissue-Specific Distribution of Cytochrome P450 1A1 and 3A in Rainbow Trout (Oncorhynchus mykiss)

Authors: Viktoriia Burkina, Vladimir Zlabek, Galia Zamaratskaia

Abstract:

Cytochromes P450 (CYP) are important family of enzymes in Phase I metabolism. Environmental pollutants often act as inducers of the gene expression and activities CYP1A1 and CYP3A-like isoforms in fish. The activities are generally measured in the fish liver or gills, and less is known about tissue distribution of expression. In present study, the CYP1A1 and CYP3A-like activities were measured in rainbow trout liver, gill, intestine, heart, brain and gonads. The activities of CYP1A1 and CYP3A-like proteins were estimated as the rates of 7-ethoxyresorufin-O-deethylation (EROD) and benzyloxy-4-trifluoromethylcoumarin-O-debenzyloxylation (BFCOD), respectively. The CYP1A1 and CYP3A-like activities were detectable in all investigated fish tissues, with the highest activity in hepatic tissue followed by heart > brain > gill > intestine > gonads. To confirm the presence of CYP1A1 in different tissues, EROD activity was measured in presence of the selective inhibitors ellipticine (CYP1A1), ketoconazole (CYP3A), 8-methoxypsoralen (human CYP2A) and diallyl sulphide (CYP2E1). It was found that ellipticine, ketoconazole and 8-methoxypsoralen inhibited hepatic EROD activity by 88-98%. Ellipticine inhibited gill, intestine, and gonad EROD activity by 50%. In conclusion, EROD and BFCOD activities were detected in rainbow trout liver, gill, intestine, heart, brain and gonads. Further studies are needed to fully identify all CYP450 isoforms responsible for these activities. Acknowledgement: The study was financially supported by the Ministry of Education, Youth and Sports of the Czech Republic - projects „CENAKVA “(No. CZ.1.05/2.1.00/01.0024), “CENAKVA Center Development “(No. CZ.1.05/2.1.00/19.0380), “CENAKVA II “(No. LO1205 under the NPU I program), and "Development of USB - International mobility (No. CZ.02.2.69/0.0/0.0/16_027/0008364).

Keywords: BFCOD, EROD, fish, phase I metabolism, selective inhibitors

Procedia PDF Downloads 151
937 Comparison of Effects over the Autonomic Nervous System When Using Force Training and Interval Training in Indoor Cycling with University Students

Authors: Daniel Botero, Oscar Rubiano, Pedro P. Barragan, Jaime Baron, Leonardo Rodriguez Perdomo, Jaime Rodriguez

Abstract:

In the last decade interval training (IT) has gained importance when is compare with strength training (ST). However, there are few studies analyzing the impact of these training over the autonomic nervous system (ANS). This work has aimed to compare the activity of the autonomic nervous system, when is expose to an IT or ST indoor cycling mode. After approval by the ethics committee, a cross-over clinical trial with 22 healthy participants (age 21 ± 3 years) was implemented. The selection of participants for the groups with sequence force-interval (F-I) and interval-force (I-F) was made randomly with assignation of 11 participants for each group. The temporal series of heart rate was obtained before and after each training using the POLAR TEAM® heart monitor. The evaluation of the ANS was performed with spectral analysis of the heart rate variability (HRV) using the fast Fourier transform (Kubios software). A training of 8 weeks in each sequence (4 weeks with each training) with an intermediate period of two weeks of washout was implemented for each group. The power parameter of the HRV in the low frequency band (LF = 0.04-0.15Hz related to the sympathetic nervous system), high frequency (HF = 0.15-0.4Hz, related to the parasympathetic) and LF/HF (with reference to a modulation of parasympathetic over the sympathetic), were calculated. Afterward, the difference between the parameters before and after was realized. Then, to evaluate statistical differences between each training was implemented the method of Wellek (Wellek and Blettner, 2012, Medicine, 109 (15), 276-81). To determine the difference of effect over parasympathetic when FT and IT are used, the T test is implemented obtaining a T value of 0.73 with p-value ≤ 0.1. For the sympathetic was obtained a T of 0.33 with p ≤ 0.1 and for LF/HF the T was 1.44 with a p ≥ 0.1. Then, the carry over effect was evaluated and was not present. Significant changes over autonomic activity with strength or interval training were not observed. However, a modulation of the parasympathetic over the sympathetic can be observed. Probably, these findings should be explained because the sample is little and/or the time of training was insufficient to generate changes.

Keywords: autonomic nervous, force training, indoor cycling, interval training

Procedia PDF Downloads 226
936 Quality Assurance in Cardiac Disorder Detection Images

Authors: Anam Naveed, Asma Andleeb, Mehreen Sirshar

Abstract:

In the article, Image processing techniques have been applied on cardiac images for enhancing the image quality. Two types of methodologies considers for survey, invasive techniques and non-invasive techniques. Different image processes for improvement of cardiac image quality and reduce the amount of radiation exposure for invasive techniques are explored. Different image processing algorithms for enhancing the noninvasive cardiac image qualities are described. Beside these two methodologies, third methodology has applied on live streaming of heart rate on ECG window for extracting necessary information, removing noise and enhancing quality. Sensitivity analyses have been carried out to investigate the impacts of cardiac images for diagnosis of cardiac arteries disease and how the enhancement on images will help the cardiologist to diagnoses disease. The paper evaluates strengths and weaknesses of different techniques applied for improved the image quality and draw a conclusion. Some specific limitations must be considered for whole survey, like the patient heart beat must be 70-75 beats/minute while doing the angiography, similarly patient weight and exposure radiation amount has some limitation.

Keywords: cardiac images, CT angiography, critical analysis, exposure radiation, invasive techniques, invasive techniques, non-invasive techniques

Procedia PDF Downloads 352
935 Characterization of Coronary Artery Obstruction and Related Findings in Ischemic Heart Patients Using Cardiac Scintigraphy

Authors: Yousif Mohamed Y. Abdallah, Eltayeb Wagi Allah Eltayeb, Mohamed E. Gar-elnabi, Mohamed Ahmed Ali

Abstract:

To characterize coronary artery obstruction and related findings in ischemic heart patients using cardiac scintigraphy for the identification of myocardial ischemia, 146 patients were studied at basal conditions and also asked for fasting after night till the intravenous injection of the radiopharmaceutical. After the injection time about 15 to 20 minutes, the patient should eat a fatty meal and chocolate for the good excretion of the gall bladder, to evaluate the performance and regional wall motion of the left ventricle (LV). The results showed that the body mass index percentage in this sample was in range of 43.05 to 61.05. The number of patients who were catheter candidates were 56 with 43% and the patients that were not candidate to cathode were 74 patients with 57% of all patients. For the group of patients where type of ischemia was assessed, 29.5% of patients had reversible posterior and inferior wall, 15.1% of patients had fixed large from apex to base, 9.6% of patients had mild basal inferior wall, 4.8 % of patients had mild anterior wall, 6.2% of patients had antro-septal and 34.9% of patients had moderate ischemia.

Keywords: myocardial ischemia, myocardial scintigraphy, contrast ventriculography, coronary artery obstruction

Procedia PDF Downloads 586
934 Simplified Measurement of Occupational Energy Expenditure

Authors: J. Wicks

Abstract:

Aim: To develop a simple methodology to allow collected heart rate (HR) data from inexpensive wearable devices to be expressed in a suitable format (METs) to quantitate occupational (and recreational) activity. Introduction: Assessment of occupational activity is commonly done by utilizing questionnaires in combination with prescribed MET levels of a vast range of previously measured activities. However for any individual the intensity of performing a specific activity can vary significantly. Ideally objective measurement of individual activity is preferred. Though there are a wide range of HR recording devices there is a distinct lack methodology to allow processing of collected data to quantitate energy expenditure (EE). The HR index equation expresses METs in relation to relative HR i.e. the ratio of activity HR to resting HR. The use of this equation provides a simple utility for objective measurement of EE. Methods: During a typical occupational work period of approximately 8 hours HR data was recorded using a Polar RS 400 wrist monitor. Recorded data was downloaded to a Windows PC and non HR data was stripped from the ASCII file using ‘Notepad’. The HR data was exported to a spread sheet program and sorted by HR range into a histogram format. Three HRs were determined, namely a resting HR (the HR delimiting the lowest 30 minutes of recorded data), a mean HR and a peak HR (the HR delimiting the highest 30 minutes of recorded data). HR indices were calculated (mean index equals mean HR/rest HR and peak index equals peak HR/rest HR) with mean and peak indices being converted to METs using the HR index equation. Conclusion: Inexpensive HR recording devices can be utilized to make reasonable estimates of occupational (or recreational) EE suitable for large scale demographic screening by utilizing the HR index equation. The intrinsic value of the HR index equation is that it is independent of factors that influence absolute HR, namely fitness, smoking and beta-blockade.

Keywords: energy expenditure, heart rate histograms, heart rate index, occupational activity

Procedia PDF Downloads 296
933 A Study of NT-ProBNP and ETCO2 in Patients Presenting with Acute Dyspnoea

Authors: Dipti Chand, Riya Saboo

Abstract:

OBJECTIVES: Early and correct diagnosis may present a significant clinical challenge in diagnosis of patients presenting to Emergency Department with Acute Dyspnoea. The common cause of acute dyspnoea and respiratory distress in Emergency Department are Decompensated Heart Failure (HF), Chronic Obstructive Pulmonary Disease (COPD), Asthma, Pneumonia, Acute Respiratory Distress Syndrome (ARDS), Pulmonary Embolism (PE), and other causes like anaemia. The aim of the study was to measure NT-pro Brain Natriuretic Peptide (BNP) and exhaled End-Tidal Carbon dioxide (ETCO2) in patients presenting with dyspnoea. MATERIAL AND METHODS: This prospective, cross-sectional and observational study was performed at the Government Medical College and Hospital, Nagpur, between October 2019 and October 2021 in patients admitted to the Medicine Intensive Care Unit. Three groups of patients were compared: (1) HFrelated acute dyspnoea group (n = 52), (2) pulmonary (COPD/PE)-related acute dyspnoea group (n = 31) and (3) sepsis with ARDS-related dyspnoea group (n = 13). All patients underwent initial clinical examination with a recording of initial vital parameters along with on-admission ETCO2 measurement, NT-proBNP testing, arterial blood gas analysis, lung ultrasound examination, 2D echocardiography, chest X-rays, and other relevant diagnostic laboratory testing. RESULTS: 96 patients were included in the study. Median NT-proBNP was found to be high for the Heart Failure group (11,480 pg/ml), followed by the sepsis group (780 pg/ml), and pulmonary group had an Nt ProBNP of 231 pg/ml. The mean ETCO2 value was maximum in the pulmonary group (48.610 mmHg) followed by Heart Failure (31.51 mmHg) and the sepsis group (19.46 mmHg). The results were found to be statistically significant (P < 0.05). CONCLUSION: NT-proBNP has high diagnostic accuracy in differentiating acute HF-related dyspnoea from pulmonary (COPD and ARDS)-related acute dyspnoea. The higher levels of ETCO2 help in diagnosing patients with COPD.

Keywords: NT PRO BNP, ETCO2, dyspnoea, lung USG

Procedia PDF Downloads 77
932 The Convergence of IoT and Machine Learning: A Survey of Real-time Stress Detection System

Authors: Shreyas Gambhirrao, Aditya Vichare, Aniket Tembhurne, Shahuraj Bhosale

Abstract:

In today's rapidly evolving environment, stress has emerged as a significant health concern across different age groups. Stress that isn't controlled, whether it comes from job responsibilities, health issues, or the never-ending news cycle, can have a negative effect on our well-being. The problem is further aggravated by the ongoing connection to technology. In this high-tech age, identifying and controlling stress is vital. In order to solve this health issue, the study focuses on three key metrics for stress detection: body temperature, heart rate, and galvanic skin response (GSR). These parameters along with the Support Vector Machine classifier assist the system to categorize stress into three groups: 1) Stressed, 2) Not stressed, and 3) Moderate stress. Proposed training model, a NodeMCU combined with particular sensors collects data in real-time and rapidly categorizes individuals based on their stress levels. Real-time stress detection is made possible by this creative combination of hardware and software.

Keywords: real time stress detection, NodeMCU, sensors, heart-rate, body temperature, galvanic skin response (GSR), support vector machine

Procedia PDF Downloads 73
931 Portable System for the Acquisition and Processing of Electrocardiographic Signals to Obtain Different Metrics of Heart Rate Variability

Authors: Daniel F. Bohorquez, Luis M. Agudelo, Henry H. León

Abstract:

Heart rate variability (HRV) is defined as the temporary variation between heartbeats or RR intervals (distance between R waves in an electrocardiographic signal). This distance is currently a recognized biomarker. With the analysis of the distance, it is possible to assess the sympathetic and parasympathetic nervous systems. These systems are responsible for the regulation of the cardiac muscle. The analysis allows health specialists and researchers to diagnose various pathologies based on this variation. For the acquisition and analysis of HRV taken from a cardiac electrical signal, electronic equipment and analysis software that work independently are currently used. This complicates and delays the process of interpretation and diagnosis. With this delay, the health condition of patients can be put at greater risk. This can lead to an untimely treatment. This document presents a single portable device capable of acquiring electrocardiographic signals and calculating a total of 19 HRV metrics. This reduces the time required, resulting in a timelier intervention. The device has an electrocardiographic signal acquisition card attached to a microcontroller capable of transmitting the cardiac signal wirelessly to a mobile device. In addition, a mobile application was designed to analyze the cardiac waveform. The device calculates the RR and different metrics. The application allows a user to visualize in real-time the cardiac signal and the 19 metrics. The information is exported to a cloud database for remote analysis. The study was performed under controlled conditions in the simulated hospital of the Universidad de la Sabana, Colombia. A total of 60 signals were acquired and analyzed. The device was compared against two reference systems. The results show a strong level of correlation (r > 0.95, p < 0.05) between the 19 metrics compared. Therefore, the use of the portable system evaluated in clinical scenarios controlled by medical specialists and researchers is recommended for the evaluation of the condition of the cardiac system.

Keywords: biological signal análisis, heart rate variability (HRV), HRV metrics, mobile app, portable device.

Procedia PDF Downloads 185
930 About Multi-Resolution Techniques for Large Eddy Simulation of Reactive Multi-Phase Flows

Authors: Giacomo Rossi, Bernardo Favini, Eugenio Giacomazzi, Franca Rita Picchia, Nunzio Maria Salvatore Arcidiacono

Abstract:

A numerical technique for mesh refinement in the HeaRT (Heat Release and Transfer) numerical code is presented. In the CFD framework, Large Eddy Simulation (LES) approach is gaining in importance as a tool for simulating turbulent combustion processes, also if this approach has an high computational cost due to the complexity of the turbulent modeling and the high number of grid points necessary to obtain a good numerical solution. In particular, when a numerical simulation of a big domain is performed with a structured grid, the number of grid points can increase so much that the simulation becomes impossible: this problem can be overcame with a mesh refinement technique. Mesh refinement technique developed for HeaRT numerical code (a staggered finite difference code) is based on an high order reconstruction of the variables at the grid interfaces by means of a least square quasi-ENO interpolation: numerical code is written in modern Fortran (2003 standard of newer) and is parallelized using domain decomposition and message passing interface (MPI) standard.

Keywords: LES, multi-resolution, ENO, fortran

Procedia PDF Downloads 366
929 Accuracy of Fitbit Charge 4 for Measuring Heart Rate in Parkinson’s Patients During Intense Exercise

Authors: Giulia Colonna, Jocelyn Hoye, Bart de Laat, Gelsina Stanley, Jose Key, Alaaddin Ibrahimy, Sule Tinaz, Evan D. Morris

Abstract:

Parkinson’s disease (PD) is the second most common neurodegenerative disease and affects approximately 1% of the world’s population. Increasing evidence suggests that aerobic physical exercise can be beneficial in mitigating both motor and non-motor symptoms of the disease. In a recent pilot study of the role of exercise on PD, we sought to confirm exercise intensity by monitoring heart rate (HR). For this purpose, we asked participants to wear a chest strap heart rate monitor (Polar Electro Oy, Kempele). The device sometimes proved uncomfortable. Looking forward to larger clinical trials, it would be convenient to employ a more comfortable and user friendly device. The Fitbit Charge 4 (Fitbit Inc) is a potentially comfortable, user-friendly solution since it is a wrist-worn heart rate monitor. Polar H10 has been used in large trials, and for our purposes, we treated it as the gold standard for the beat-to-beat period (R-R interval) assessment. In previous literature, it has been shown that Fitbit Charge 4 has comparable accuracy to Polar H10 in healthy subjects. It has yet to be determined if the Fitbit is as accurate as the Polar H10 in subjects with PD or in clinical populations, generally. Goal: To compare the Fitbit Charge 4 to the Polar H10 for monitoring HR in PD subjects engaging in an intensive exercise program. Methods: A total of 596 exercise sessions from 11 subjects (6 males) were collected simultaneously by both devices. Subjects with early-stage PD (Hoehn & Yahr <=2) were enrolled in a 6 months exercise training program designed for PD patients. Subjects participated in 3 one-hour exercise sessions per week. They wore both Fitbit and Polar H10 during each session. Sessions included rest, warm-up, intensive exercise, and cool-down periods. We calculated the bias in the HR via Fitbit under rest (5min) and intensive exercise (20min) by comparing the mean HR during each of the periods to the respective means measured by the Polar (HRFitbit – HRPolar). We also measured the sensitivity and specificity of Fitbit for detecting HRs that exceed the threshold for intensive exercise, defined as 70% of an individual’s theoretical maximum HR. Different types of correlation between the two devices were investigated. Results: The mean bias was 1.68 bpm at rest and 6.29 bpm during high intensity exercise, with an overestimation by Fitbit in both conditions. The mean bias of Fitbit across both rest and intensive exercise periods was 3.98 bpm. The sensitivity of the device in identifying high intensity exercise sessions was 97.14 %. The correlation between the two devices was non-linear, suggesting a saturation tendency of Fitbit to saturate at high values of HR. Conclusion: The performance of Fitbit Charge 4 is comparable to Polar H10 for assessing exercise intensity in a cohort of PD subjects. The device should be considered a reasonable replacement for the more cumbersome chest strap technology in future similar studies of clinical populations.

Keywords: fitbit, heart rate measurements, parkinson’s disease, wrist-wearable devices

Procedia PDF Downloads 111
928 Formation and Development of Polyspecies Biofilm on the Surface of Ti-7.5Mo Nanotubes Growth

Authors: Escada A. L. A., Pereira C. A., Jorge A. O. C., Alves Claro A. P. R.

Abstract:

In the present work, a susceptibility and efficacy of the Ti–7.5Mo alloy nanotube and Ti–7.5Mo alloy to bacterial biofilm formation after surface treatment was evaluated. The Ti–7.5Mo alloy was obtained in arc furnace under an argon atmosphere. Ingots were then homogenized under vacuum at 1100 ◦C for 86.4 ks to eliminate chemical segregation and after cold worked discs were cutting. Nanotubes were processed using anodic oxidation in 0.25% NH4F electrolyte solution. Biofilms were grown in discs immersed in sterile brain heart infusion broth (BHI) containing 5% sucrose, inoculated with microbial suspension (106 cells/ml) and incubated for 5 days. Next, the discs were placed in tubes with sterile physiological solution 0.9% sodium chloride (NaCl) and sonicated for to disperse the biofilms. Tenfold serial dilutions were carried and aliquots seeded in selective agar, which were then incubated for 48 h. Then, the numbers CFU/ml (log 10) were counted and analyzed statistically. Scanning electron microscopy (SEM) on discs with biofilms groupswas performed, atomic force microscope (AFM) and contact angle. The results show that there is no difference in bacterial adhesion between Ti–7.5Mo alloy nanotube pure titanium and Ti–7.5Mo alloy.

Keywords: biofilm, titanium alloy, brain heart infusion, scanning electron microscopy

Procedia PDF Downloads 318
927 Contactless Heart Rate Measurement System based on FMCW Radar and LSTM for Automotive Applications

Authors: Asma Omri, Iheb Sifaoui, Sofiane Sayahi, Hichem Besbes

Abstract:

Future vehicle systems demand advanced capabilities, notably in-cabin life detection and driver monitoring systems, with a particular emphasis on drowsiness detection. To meet these requirements, several techniques employ artificial intelligence methods based on real-time vital sign measurements. In parallel, Frequency-Modulated Continuous-Wave (FMCW) radar technology has garnered considerable attention in the domains of healthcare and biomedical engineering for non-invasive vital sign monitoring. FMCW radar offers a multitude of advantages, including its non-intrusive nature, continuous monitoring capacity, and its ability to penetrate through clothing. In this paper, we propose a system utilizing the AWR6843AOP radar from Texas Instruments (TI) to extract precise vital sign information. The radar allows us to estimate Ballistocardiogram (BCG) signals, which capture the mechanical movements of the body, particularly the ballistic forces generated by heartbeats and respiration. These signals are rich sources of information about the cardiac cycle, rendering them suitable for heart rate estimation. The process begins with real-time subject positioning, followed by clutter removal, computation of Doppler phase differences, and the use of various filtering methods to accurately capture subtle physiological movements. To address the challenges associated with FMCW radar-based vital sign monitoring, including motion artifacts due to subjects' movement or radar micro-vibrations, Long Short-Term Memory (LSTM) networks are implemented. LSTM's adaptability to different heart rate patterns and ability to handle real-time data make it suitable for continuous monitoring applications. Several crucial steps were taken, including feature extraction (involving amplitude, time intervals, and signal morphology), sequence modeling, heart rate estimation through the analysis of detected cardiac cycles and their temporal relationships, and performance evaluation using metrics such as Root Mean Square Error (RMSE) and correlation with reference heart rate measurements. For dataset construction and LSTM training, a comprehensive data collection system was established, integrating the AWR6843AOP radar, a Heart Rate Belt, and a smart watch for ground truth measurements. Rigorous synchronization of these devices ensured data accuracy. Twenty participants engaged in various scenarios, encompassing indoor and real-world conditions within a moving vehicle equipped with the radar system. Static and dynamic subject’s conditions were considered. The heart rate estimation through LSTM outperforms traditional signal processing techniques that rely on filtering, Fast Fourier Transform (FFT), and thresholding. It delivers an average accuracy of approximately 91% with an RMSE of 1.01 beat per minute (bpm). In conclusion, this paper underscores the promising potential of FMCW radar technology integrated with artificial intelligence algorithms in the context of automotive applications. This innovation not only enhances road safety but also paves the way for its integration into the automotive ecosystem to improve driver well-being and overall vehicular safety.

Keywords: ballistocardiogram, FMCW Radar, vital sign monitoring, LSTM

Procedia PDF Downloads 73