IEEE Open Journal of Engineering in Medicine and Biology最新文献

{"title":"Feasibility of an Inductive Pedicle Screw Loosening Detection Concept Using a Pulse Induction Metal Detector","authors":"Ramon Rohner;David E. Bauer;Martin Hartmann;Tobias Götschi;Mazda Farshad;Jonas Widmer","doi":"10.1109/OJEMB.2024.3482878","DOIUrl":"https://doi.org/10.1109/OJEMB.2024.3482878","url":null,"abstract":"<italic>Introduction:</i>\u0000 Pedicle screw loosening is a major problem in spine surgery. Computed tomography (CT) is the gold standard to diagnose screw loosening. Disadvantages of CT include low sensitivity and specificity for the detection of loosened screws as well as the need for radiation exposure. The aim of this study was to provide a proof of concept of a novel, non-invasive, inductive sensing device for transcutaneous detection of screw loosening using a pulse induction metal detector. \u0000<italic>Materials/Methods:</i>\u0000 Two fresh frozen human cadavers were initially instrumented in the lumbar spinal region (L1 to L5). After assessment of the sensing device behavior using a wooden beam and 3D printed place holders of predefined distances, the ability of implant detection and screw stability determination were assessed during two experiments. Pedicle screw loosening was induced using 3D printed drill/loosening guides during the instrumentation of the lumbar spine. Screw stability was determined by applying weight to the spinous processes of interest and measuring the relative movement of the pedicle screw using the inductive sensor coil. \u0000<italic>Results:</i>\u0000 The sensitivity of our detection coil for an implant movement measurement showed to be high at close distances (60mV voltage change per mm movement), with signal amplitude vanishing at sensing distances of 50mm or greater. Signal amplitude significantly (p < .05) differed with the number of instrumented levels. When differentiating between instrumentation with and without loosened screws, significant (p < .05) mean differences were found in half of all comparative cases. All these differences were smaller than the predefined signal voltage threshold of (60 mV/mm). \u0000<italic>Discussion/Conclusion:</i>\u0000 In this study, the feasibility of a new, inductive and non-invasive sensor concept was tested. While the basic principle of the approach is promising, our implementation was not successful in demonstrating sufficient sensitivity for the required detectability. It appears conceivable that the concept can be successfully implemented with more sensitive sensors and more complex evaluation methods.","PeriodicalId":33825,"journal":{"name":"IEEE Open Journal of Engineering in Medicine and Biology","volume":"6 ","pages":"113-118"},"PeriodicalIF":2.7,"publicationDate":"2024-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10720821","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142636530","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimal Transport Based Graph Kernels for Drug Property Prediction","authors":"Mohammed Aburidi;Roummel Marcia","doi":"10.1109/OJEMB.2024.3480708","DOIUrl":"https://doi.org/10.1109/OJEMB.2024.3480708","url":null,"abstract":"<italic>Objective:</i>\u0000 The development of pharmaceutical agents relies heavily on optimizing their pharmacodynamics, pharmacokinetics, and toxicological properties, collectively known as ADMET (Absorption, Distribution, Metabolism, Excretion, and Toxicity). Accurate assessment of these properties during the early stages of drug development is challenging due to resource-intensive experimental evaluation and limited comprehensive data availability. To overcome these obstacles, there has been a growing reliance on computational and predictive tools, leveraging recent advancements in machine learning and graph-based methodologies. This study presents an innovative approach that harnesses the power of optimal transport (OT) theory to construct three graph kernels for predicting drug ADMET properties. This approach involves the use of graph matching to create a similarity matrix, which is subsequently integrated into a predictive model. \u0000<italic>Results:</i>\u0000 Through extensive evaluations on 19 distinct ADMET datasets, the potential of this methodology becomes evident. The OT-based graph kernels exhibits exceptional performance, outperforming state-of-the-art graph deep learning models in 9 out of 19 datasets, even surpassing the most impactful Graph Neural Network (GNN) that excels in 4 datasets. Furthermore, they are very competitive in 2 additional datasets. \u0000<italic>Conclusion:</i>\u0000 Our proposed novel class of OT-based graph kernels not only demonstrates a high degree of effectiveness and competitiveness but also, in contrast to graph neural networks, offers interpretability, adaptability and generalizability across multiple datasets.","PeriodicalId":33825,"journal":{"name":"IEEE Open Journal of Engineering in Medicine and Biology","volume":"6 ","pages":"152-157"},"PeriodicalIF":2.7,"publicationDate":"2024-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10716457","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142905935","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental Evaluation of a New Perfusion Machine Using Normothermic Cycles on Explanted Livers","authors":"Eleonora Barcali;Lorenzo Maggi;Rebecca Panconesi;Fabio Staderini;Leonardo Bocchi;Cosimo Nardi;Nadia Navari;Adriano Peris;Matteo Risaliti;Mauricio F. Carvalho;Fabio Marra;Philipp Dutkowski;Gian Luca Grazi;Andrea Schlegel;Filippo Bigi;Mattia Dimitri;Andrea Corvi","doi":"10.1109/OJEMB.2024.3478791","DOIUrl":"https://doi.org/10.1109/OJEMB.2024.3478791","url":null,"abstract":"<italic>Goal:</i>\u0000 Organ perfusion is a vast subject with several techniques, the most common being Hypothermic Machine Perfusion (HMP) and Normothermic Machine Perfusion (NMP). In this paper, a new machine developed at the Biolab of the University of Florence has been tested to validate its capability to perform a well-controlled Oxygenated Rewarming (COR) phase and maintain stability during the NMP phase. \u0000<italic>Methods:</i>\u0000 The tests (n = 5) were conducted on fresh porcine livers and evaluated according to liver perfusion standards. The developed machine is based on a previous version, with an integrated control and sensor system and a complete mechanical and electronic redesign. \u0000<italic>Results:</i>\u0000 The results demonstrate the excellent usability of the machine and its ability to effectively maintain the organs in good condition. The new system performed well, and the measures made on the livers were satisfactory for good preservation of the organ. \u0000<italic>Conclusion:</i>\u0000 This study showed the effectiveness of the developed machine. Future development of the system will include a more sophisticated control system to ensure the correct parameters for perfusion.","PeriodicalId":33825,"journal":{"name":"IEEE Open Journal of Engineering in Medicine and Biology","volume":"6 ","pages":"82-88"},"PeriodicalIF":2.7,"publicationDate":"2024-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10713905","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142600236","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sub-Chronic Peroneal Nerve Stimulation Lowers Ambulatory Blood Pressure in Spontaneously Hypertensive Rats","authors":"K. Romero;M.A. Gonzalez-Gonzalez;D. Lloyd;K. Nguyen;N. Eli;Y. Akay;W. Vongpatanasin;S. Smith;M. Akay;MI Romero-Ortega","doi":"10.1109/OJEMB.2024.3477411","DOIUrl":"https://doi.org/10.1109/OJEMB.2024.3477411","url":null,"abstract":"<italic>Objective:</i>\u0000 Acute electrical stimulation of the common peroneal nerve (cPNS) has been shown to cause an immediate reduction in systolic blood pressure (SBP) in spontaneous hypertense rats (SHR), but the effect of this treatment in sub-chronic ambulatory SBP is unknown. Here we developed an implantable wireless WNClip neural stimulator to test the efficacy of 5-week cPNS as a treatment for hypertension. \u0000<italic>Results:</i>\u0000 Daily cPNS 2 Hz monophasic stimulation at threshold for 8 minutes every day for five weeks, reduced SBP in WKY animals by −4 mm Hg, and in SHR animals by −21 mmHg in week 5 (p < 0.01). Ambulatory SBP measured daily recorded approximately twenty-four hours after the cPNS treatment, showed a significant reduction from the first (176.6 ± 24.1 mm Hg; n = 5) to the last week of treatment (165.7± 42.7 mm Hg; n = 4), a −9 mm Hg reduction (p < 0.01). Evaluation of heart rate during the treatment showed no significant difference caused by the daily 8-minute cPNS. \u0000<italic>Conclusions:</i>\u0000 Electrical stimulation of the common peroneal nerve induced a reduction in SBP that is comparable to that reportedly achieved pharmacologically by ACE inhibitor Ramipril, or by renal denervation procedures. These results support the notion that neuromodulation of the common peroneal nerve can serve as an alternative treatment for drug resistant hypertension.","PeriodicalId":33825,"journal":{"name":"IEEE Open Journal of Engineering in Medicine and Biology","volume":"6 ","pages":"140-146"},"PeriodicalIF":2.7,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10713865","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142713804","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Neural Implants Without Active Implanted Electronics: Possibilities and Limitations of Transcutaneous Coupling in Miniaturized Active Implants","authors":"Patrick Kiele;Gregor Laengle;Martin Schmoll;Cristian Pasluosta;Ronny Pfeifer;Martin Schuettler;Oskar Aszmann;Thomas Stieglitz","doi":"10.1109/OJEMB.2024.3477267","DOIUrl":"https://doi.org/10.1109/OJEMB.2024.3477267","url":null,"abstract":"<italic>Goal:</i>\u0000 Transcutaneous coupling scheme for wireless powering and signal in active implants are known for more than a decade. This study aimed to investigate the in vivo behavior of this approach to drive multiple channels of an implanted peripheral nerve interfaces. \u0000<italic>Methods:</i>\u0000 The stimulation signals were transmitted through the skin over two contacts to an intracorporeal counterpart which was connected to a cuff electrode with two channels. EMG after stimulation was measured to establish recruitment curves. \u0000<italic>Results:</i>\u0000 Limitations of transcutaneous coupling were found in the feasible complexity of the system. High electrical crosstalk in a multi-channel system reduces this approach to low channel applications, such as pain treatment. No significant influence of the pulse width or extracorporeal stimulation amplitude on the electrical crosstalk was observed. \u0000<italic>Conclusions:</i>\u0000 The study's findings provide insight into the behavior of the transcutaneous coupling scheme in vivo and highlight the limitations and areas of application. Our results indicate that transcutaneous coupling schemes are a promising alternative approach for wireless powering of implants, as it does not require complex implanted electronics, expensive sophisticated electronics, and hermetic enclosures. Physical constraints, however, limit the use in highly selective nerve stimulation scenarios.","PeriodicalId":33825,"journal":{"name":"IEEE Open Journal of Engineering in Medicine and Biology","volume":"6 ","pages":"69-74"},"PeriodicalIF":2.7,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10710177","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142600238","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optical Taxonomic Signal and the Diagnosis of Alzheimer's Disease","authors":"Frank A. Greco;Brent R. Schell;Eugene B. Hanlon","doi":"10.1109/OJEMB.2024.3477449","DOIUrl":"https://doi.org/10.1109/OJEMB.2024.3477449","url":null,"abstract":"<italic>Goal:</i>\u0000 We previously demonstrated that near-infrared spectroscopy in vivo presents spectral features at 895 and 861 nm that accurately classify Alzheimer's disease, mild cognitive impairment, and age-matched control subjects. Our purpose here is to associate the 895 nm signal with \u0000<inline-formula><tex-math>$beta$</tex-math></inline-formula>\u0000-amyloid. \u0000<italic>Methods:</i>\u0000 We applied our feature selection technique to subjects with and without leptomeningeal amyloid. We developed a novel concept, optical taxonomic signal, to determine the dependence of signal on source-detector distance. \u0000<italic>Results:</i>\u0000 Features at 891 and 768 nm discriminate between subjects with and without leptomeningeal \u0000<inline-formula><tex-math>$beta$</tex-math></inline-formula>\u0000-amyloid. The variation of optical taxonomic signal with source-detector distance indicates that both signals come from the leptomeninges and not cerebral cortex. The two features are highly correlated and likely result from the same cellular material. \u0000<italic>Conclusions:</i>\u0000 The discovery of an 891 nm feature that clearly depends upon the presence of \u0000<inline-formula><tex-math>$beta$</tex-math></inline-formula>\u0000-amyloid supports our hypothesis that the 895 nm feature previously discovered also reports \u0000<inline-formula><tex-math>$beta$</tex-math></inline-formula>\u0000-amyloid.","PeriodicalId":33825,"journal":{"name":"IEEE Open Journal of Engineering in Medicine and Biology","volume":"6 ","pages":"107-112"},"PeriodicalIF":2.7,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10712650","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142636406","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Miniaturized Devices for Isothermal Amplification and Photometric Quantification of Pseudomonas Aeruginosa","authors":"Ramya Priya;Satish Kumar Dubey;Sanket Goel","doi":"10.1109/OJEMB.2024.3477315","DOIUrl":"https://doi.org/10.1109/OJEMB.2024.3477315","url":null,"abstract":"<italic>Goal:</i>\u0000 This study introduced a proof-of-concept prototype for isothermal recombinase polymerase amplification (RPA) with miniaturized photometric detection, enabling rapid P. aeruginosa detection. \u0000<italic>Methods:</i>\u0000 The researchers conducted the amplification process within a microchamber with a diameter of 10 mm, utilizing a standalone Thermostat driven thermal management setup. RPA, an amplification technique was employed, which required a lower operating temperature of 37 °C–40 °C to complete the reaction. The amplified amplicon was labeled with a fluorophore reporter, stimulated by an LED light source, and detected in real-time using a photodiode. \u0000<italic>Results:</i>\u0000 The developed prototype successfully demonstrated the rapid detection of P. aeruginosa using the RPA assay. The process only required the utilization of 0.04 ng of working concentration of DNA. The entire process, from amplification to detection, could be completed in over 15 minutes. The platform showed enhanced sensitivity and specificity, providing a cost-effective and accurate solution for on-site detection/quantification of pathogens. \u0000<italic>Conclusions:</i>\u0000 The integration of isothermal RPA with the miniaturized photometric detection platform proved successful in achieving the goal of rapid and specific pathogen detection. This study proved the benefits of Isothermal Nucleic Acid Amplification Technology (INAAT), emphasizing its potential as an accessible, user-friendly point-of-care technology for resource-constrained institutions. The RPA-based prototype demonstrated capability without requiring costly laboratory equipment or expertise. The developed platform, when combined with Internet of Things (IoT) enabled cloud platform, also allowed remote monitoring of data. Overall, the methodology presented in this study offered a cost-effective, accurate, and convenient solution for on-site testing in resource-limited settings.","PeriodicalId":33825,"journal":{"name":"IEEE Open Journal of Engineering in Medicine and Biology","volume":"6 ","pages":"133-139"},"PeriodicalIF":2.7,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10710143","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142713806","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Feasibility of Using Autonomous Ankle Exoskeletons to Augment Community Walking in Cerebral Palsy","authors":"Collin D. Bowersock;Zachary F. Lerner","doi":"10.1109/OJEMB.2024.3475911","DOIUrl":"https://doi.org/10.1109/OJEMB.2024.3475911","url":null,"abstract":"<italic>Objective:</i>\u0000 This pilot study investigated the feasibility and efficacy of using autonomous ankle exoskeletons in community settings among individuals with cerebral palsy (CP). Five participants completed two structured community walking protocols: a week-long ankle exoskeleton acclimation and training intervention, and a dose-matched Sham intervention of unassisted walking. \u0000<italic>Results:</i>\u0000 Results demonstrated significant improvements in acclimatized walking performance with the ankle exoskeleton, including increased speed and stride length. Participants also reported increased enjoyment and perceived benefits of using the exoskeleton. While ankle exoskeleton training did not lead to significant improvements in unassisted walking, this study demonstrates the feasibility of using ankle exoskeletons in the real world by people with CP. \u0000<italic>Conclusions:</i>\u0000 This study highlights the potential of wearable exoskeletons to augment community walking performance in CP, laying a foundation for further exploration in real-world environments.","PeriodicalId":33825,"journal":{"name":"IEEE Open Journal of Engineering in Medicine and Biology","volume":"6 ","pages":"75-81"},"PeriodicalIF":2.7,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10709375","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142600237","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Machine Learning-Based X-Ray Projection Interpolation for Improved 4D-CBCT Reconstruction","authors":"Jayroop Ramesh;Donthi Sankalpa;Rohan Mitra;Salam Dhou","doi":"10.1109/OJEMB.2024.3459622","DOIUrl":"10.1109/OJEMB.2024.3459622","url":null,"abstract":"<italic>Goal:</i>\u0000 Respiration-correlated cone-beam computed tomography (4D-CBCT) is an X-ray-based imaging modality that uses reconstruction algorithms to produce time-varying volumetric images of moving anatomy over a cycle of respiratory motion. The quality of the produced images is affected by the number of CBCT projections available for reconstruction. Interpolation techniques have been used to generate intermediary projections to be used, along with the original projections, for reconstruction. Transfer learning is a powerful approach that harnesses the ability to reuse pre-trained models in solving new problems. \u0000<italic>Methods:</i>\u0000 Several state-of-the-art pre-trained deep learning models, used for video frame interpolation, are utilized in this work to generate intermediary projections. Moreover, a novel regression predictive modeling approach is also proposed to achieve the same objective. Digital phantom and clinical datasets are used to evaluate the performance of the models. \u0000<italic>Results:</i>\u0000 The results show that the Real-Time Intermediate Flow Estimation (RIFE) algorithm outperforms the others in terms of the Structural Similarity Index Method (SSIM): 0.986 \u0000<inline-formula><tex-math>$pm$</tex-math></inline-formula>\u0000 0.010, Peak Signal to Noise Ratio (PSNR): 44.13 \u0000<inline-formula><tex-math>$pm$</tex-math></inline-formula>\u0000 2.76, and Mean Square Error (MSE): 18.86 \u0000<inline-formula><tex-math>$pm$</tex-math></inline-formula>\u0000 206.90 across all datasets. Moreover, the interpolated projections were used along with the original ones to reconstruct a 4D-CBCT image that was compared to that reconstructed from the original projections only. \u0000<italic>Conclusions:</i>\u0000 The reconstructed image using the proposed approach was found to minimize the streaking artifacts, thereby enhancing the image quality. This work demonstrates the advantage of using general-purpose transfer learning algorithms in 4D-CBCT image enhancement.","PeriodicalId":33825,"journal":{"name":"IEEE Open Journal of Engineering in Medicine and Biology","volume":"6 ","pages":"61-67"},"PeriodicalIF":2.7,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10678916","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142225756","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of Brain Function After 240 Days Confinement Using Functional Near Infrared Spectroscopy","authors":"Fares Al-Shargie;Usman Tariq;Saleh Al-Ameri;Abdulla Al-Hammadi;Schastlivtseva Daria Vladimirovna;Hasan Al-Nashash","doi":"10.1109/OJEMB.2024.3457240","DOIUrl":"10.1109/OJEMB.2024.3457240","url":null,"abstract":"Future space exploration missions will expose astronauts to various stressors, making the early detection of mental stress crucial for prolonged missions. Our study proposes using functional near infrared spectroscopy (fNIRS) combined with multiple machine learning models to assess the level of mental stress. \u0000<italic>Objective:</i>\u0000 The objective is to identify and quantify stress levels during 240 days confinement scenario. In this study, we utilize a diverse set of stress indicators including salivary alpha amylase (sAA) levels, reaction time (RT) to stimuli, accuracy of target detection, and power spectral density (PSD), in conjunction with functional connectivity networks (FCN). We estimate the PSD using Fast Fourier Transform (FFT) and the FCN using partial directed coherence. \u0000<italic>Results:</i>\u0000 Our findings reveal several intriguing insights. The sAA levels increased from the first 30 days in confinement to the culmination of the lengthy 240-day mission, suggesting a cumulative impact of stress. Conversely, RT and the accuracy of target detection exhibit significant fluctuations over the course of the mission. The power spectral density shows a significant increase with time-in-mission across all participants in most of the frontal area. The FCN shows a significant decrease in most of the right frontal areas. Five different machine learning classifiers are employed to differentiate between two levels of stress resulting in impressive classification accuracy rates: 96.44% with-nearest neighbor (KNN), 95.52% with linear discriminant analysis (LDA), 88.71% with Naïve Bayes (NB), 87.41 with decision trees (DT) and 96.48% with Support Vector Machine (SVM). In conclusion, this study demonstrates the effectiveness of combining functional near infrared spectroscopy (fNIRS) with multiple machine learning models to accurately assess and quantify mental stress levels during prolonged space missions, providing a promising approach for early stress detection in astronauts.","PeriodicalId":33825,"journal":{"name":"IEEE Open Journal of Engineering in Medicine and Biology","volume":"6 ","pages":"54-60"},"PeriodicalIF":2.7,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10670317","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142200295","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}