Journal of Medical Engineering and Technology最新文献

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Wireless CardioS framework for continuous ECG acquisition. 用于连续心电采集的无线CardioS框架。
Journal of Medical Engineering and Technology Pub Date : 2023-04-01 Epub Date: 2024-01-22 DOI: 10.1080/03091902.2023.2267116
N Sriraam, Avvaru Srinivasulu, V S Prakash
{"title":"Wireless CardioS framework for continuous ECG acquisition.","authors":"N Sriraam, Avvaru Srinivasulu, V S Prakash","doi":"10.1080/03091902.2023.2267116","DOIUrl":"10.1080/03091902.2023.2267116","url":null,"abstract":"<p><p>A first-level textile-based electrocardiogram (ECG) monitoring system referred to as \"CardioS\" (cardiac sensor) for continuous health monitoring applications is proposed in this study to address the demand for resource-constrained environments. and the signal quality assessment of a wireless CardioS was studied. The CardioS consists of a Lead-I ECG signal recorded wirelessly using silver-plated nylon woven (Ag-NyW) dry textile electrodes to compare the results of wired wearable Ag-NyW textile electrode-based ECG acquisition system and CardioS. The effect of prolonged usage of Ag-NyW dry electrodes on electrode impedance was tested in the current work. In addition, electrode half-cell potential was measured to validate the range of Ag-NyW dry electrodes for ECG signal acquisition. Further, the quality of signals recorded by the proposed wireless CardioS framework was evaluated and compared with clinical disposable (Ag-AgCl Gel) electrodes. The signal quality was assessed in terms of mean magnitude coherence spectra, signal cross-correlation, signal-to-noise-band ratio (<i>S</i><sub>band</sub>/<i>N</i><sub>band</sub>), crest factor, low and high band powers and power spectral density. The experimental results showed that the impedance was increased by 2.5-54.6% after six weeks of continuous usage. This increased impedance was less than 1 MΩ/cm<sup>2</sup>, as reported in the literature. The half-cell potential of the Ag-NyW textile electrode obtained was 80 mV, sufficient to acquire the ECG signal from the human body. All the fidelity parameters measured by Ag-NyW textile electrodes were correlated with standard disposable electrodes. The cardiologists validated all the measurements and confirmed that the proposed framework exhibited good performance for ECG signal acquisition from the five healthy subjects. As a result of its low-cost architecture, the proposed CardioS framework can be used in resource-constrained environments for ECG monitoring.</p>","PeriodicalId":39637,"journal":{"name":"Journal of Medical Engineering and Technology","volume":" ","pages":"201-216"},"PeriodicalIF":0.0,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71427661","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Computational study and validation of a novel passive hand tremor attenuator. 一种新型被动手颤衰减器的计算研究与验证。
Journal of Medical Engineering and Technology Pub Date : 2023-04-01 DOI: 10.1080/03091902.2022.2134482
Manthan Shah, Dylan Goode, Hadi Mohammadi
{"title":"Computational study and validation of a novel passive hand tremor attenuator.","authors":"Manthan Shah,&nbsp;Dylan Goode,&nbsp;Hadi Mohammadi","doi":"10.1080/03091902.2022.2134482","DOIUrl":"https://doi.org/10.1080/03091902.2022.2134482","url":null,"abstract":"<p><p>Tremors are a prevalent movement disorder due to a nervous system condition that leads to involuntary muscle movements observed in patients. This paper converts the tremorous anatomical human arm model to a single degree of freedom (SDOF) forced vibration problem. The mathematical modelling with Euler-Lagrange's equation is performed for the SDOF human arm model with two different potential vibration absorbers. A computational study is conducted on MATLAB Simulink by MathWorks Inc. (Natick, MA) to compare two absorbers, and the results are verified on the multibody dynamics simulation solution software, MSC Adams by Hexagon AB. It is concluded that the T beam-shaped vibration absorber represented a higher amplitude reduction, up to 80%, compared to the inertial mass absorber, which had an amplitude reduction of 65% over the range of frequencies. Experiments conducted with the T beam absorber prototype also support the computational findings. Future research focuses on designing an ergonomic wearable device with a proposed T-beam absorber that can passively attenuate the tremor at various frequencies.</p>","PeriodicalId":39637,"journal":{"name":"Journal of Medical Engineering and Technology","volume":"47 3","pages":"157-164"},"PeriodicalIF":0.0,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9720573","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Developing of an open-source low-cost ventilator based on turbine technology. 基于涡轮技术的开源低成本通风机的研制。
Journal of Medical Engineering and Technology Pub Date : 2023-04-01 Epub Date: 2024-01-22 DOI: 10.1080/03091902.2023.2286945
Bashar Al-Haj Moh'd
{"title":"Developing of an open-source low-cost ventilator based on turbine technology.","authors":"Bashar Al-Haj Moh'd","doi":"10.1080/03091902.2023.2286945","DOIUrl":"10.1080/03091902.2023.2286945","url":null,"abstract":"<p><p>The COVID-19 pandemic has revealed numerous global health system deficits, even in developed countries. The high cost and shortage of treatment, health care, and medical devices are the reasons. Aside from new mutations, the availability of respirators is an urgent concern, especially in developing countries. Even after the pandemic, respiratory diseases are among the most prevalent diseases. Researchers can help reduce treatment costs by offering scalable, open-source solutions that are manufacturable. Since March 2020, serious efforts have been made to reduce the problems caused by the lack of respirators at the lowest possible cost. In this research paper, a unique and integrated solution for a fully automatic ventilator is presented and described. The design considers the cost, speed of assembly, safety, ease of use, robustness, portability issues, and scalability to fit all requirements for emergency ventilation. Furthermore, the device was developed using turbine technology to generate air pressure. The work describes a low-cost alternative ventilator that uses a novel proportional-valve approach to control oxygen mixing process, control circuit, and control algorithm. The current software supports pressure mode controllers, and it can be upgraded to volume-mode or dual mode without any modifications in the hardware. In addition, the hardware, particularly the electronic circuit, has idle input/output ports for further development. Based on the evaluations of the developed ventilator using an artificial lung, the system exhibited acceptable accuracy regarding to the pressure, leak compensation, and oxygen concentration levels. The designated safety conditions have been met, and the safety alarms tripped according to any violations. Moreover, all design files are provided with clear instructions to rebuild the device, despite the complexity of electronics assembly. The system can be described as a development kit, which can shorten the time for researchers/manufacturers to develop a device equivalent to the expensive devices available in the market.</p>","PeriodicalId":39637,"journal":{"name":"Journal of Medical Engineering and Technology","volume":" ","pages":"217-233"},"PeriodicalIF":0.0,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138463354","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Towards using a multi-material, pellet-fed additive manufacturing platform to fabricate novel imaging phantoms. 朝着使用多材料、颗粒喂料的增材制造平台制造新型成像幻影的方向发展。
Journal of Medical Engineering and Technology Pub Date : 2023-04-01 DOI: 10.1080/03091902.2023.2193267
Franck Lacan, Richard Johnston, Rhys Carrington, Emiliano Spezi, Peter Theobald
{"title":"Towards using a multi-material, pellet-fed additive manufacturing platform to fabricate novel imaging phantoms.","authors":"Franck Lacan,&nbsp;Richard Johnston,&nbsp;Rhys Carrington,&nbsp;Emiliano Spezi,&nbsp;Peter Theobald","doi":"10.1080/03091902.2023.2193267","DOIUrl":"https://doi.org/10.1080/03091902.2023.2193267","url":null,"abstract":"<p><p>The design freedom afforded by additive manufacturing (AM) is now being leveraged across multiple applications, including many in the fields of imaging for personalised medicine. This study utilises a pellet-fed, multi-material AM machine as a route to fabricating new imaging phantoms, used for developing and refining algorithms for the detection of subtle soft tissue anomalies. Traditionally comprising homogeneous materials, higher-resolution scanning now allows for heterogeneous, multi-material phantoms. Polylactic acid (PLA), a thermoplastic urethane (TPU) and a thermoplastic elastomer (TPE) were investigated as potential materials. Manufacturing accuracy and precision were assessed relative to the digital design file, whilst the potential to achieve structural heterogeneity was evaluated by quantifying infill density <i>via</i> micro-computed tomography. Hounsfield units (HU) were also captured <i>via</i> a clinical scanner. The PLA builds were consistently too small, by 0.2 - 0.3%. Conversely, TPE parts were consistently larger than the digital file, though by only 0.1%. The TPU components had negligible differences relative to the specified sizes. The accuracy and precision of material infill were inferior, with PLA exhibiting greater and lower densities relative to the digital file, across the 3 builds. Both TPU and TPE produced infills that were too dense. The PLA material produced repeatable HU values, with poorer precision across TPU and TPE. All HU values tended towards, and some exceeded, the reference value for water (0 HU) with increasing infill density. These data have demonstrated that pellet-fed AM can produce accurate and precise structures, with the potential to include multiple materials providing an opportunity for more realistic and advanced phantom designs. In doing so, this will enable clinical scientists to develop more sensitive applications aimed at detecting ever more subtle variations in tissue, confident that their calibration models reflect their intended designs.</p>","PeriodicalId":39637,"journal":{"name":"Journal of Medical Engineering and Technology","volume":"47 3","pages":"189-196"},"PeriodicalIF":0.0,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9373444","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
News and Product Update. 新闻和产品更新。
Journal of Medical Engineering and Technology Pub Date : 2023-04-01 Epub Date: 2023-05-10 DOI: 10.1080/03091902.2023.2198436
John Fenner
{"title":"News and Product Update.","authors":"John Fenner","doi":"10.1080/03091902.2023.2198436","DOIUrl":"https://doi.org/10.1080/03091902.2023.2198436","url":null,"abstract":"","PeriodicalId":39637,"journal":{"name":"Journal of Medical Engineering and Technology","volume":"47 4","pages":"262-264"},"PeriodicalIF":0.0,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139513782","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Comparison of pulse rate variability from post-auricula and heart rate variability during different body states for healthy subjects. 健康人不同身体状态下听诊后脉搏变异性与心率变异性的比较。
Journal of Medical Engineering and Technology Pub Date : 2023-04-01 DOI: 10.1080/03091902.2023.2175061
Yusheng Qi, Aihua Zhang, Yurun Ma, Tingting Chang, Jianwen Xu
{"title":"Comparison of pulse rate variability from post-auricula and heart rate variability during different body states for healthy subjects.","authors":"Yusheng Qi,&nbsp;Aihua Zhang,&nbsp;Yurun Ma,&nbsp;Tingting Chang,&nbsp;Jianwen Xu","doi":"10.1080/03091902.2023.2175061","DOIUrl":"https://doi.org/10.1080/03091902.2023.2175061","url":null,"abstract":"<p><p>Heart rate variability (HRV) extracted from the electrocardiogram (ECG) is an essential indicator for assessing the autonomic nervous system in clinical. Some scholars have studied the feasibility of pulse rate variability (PRV) instead of HRV. However, there is little qualitative research in different body states. In this paper, the photoplethysmography (PPG) of postauricular and finger and the ECG of fifteen subjects were synchronously collected for comparative analysis. The eleven experiments were designed according to the daily living state, including the stationary state, limb movement state, and facial movement state. The substitutability of nine variables was investigated in the time, frequency, and nonlinearity domain by Passing Bablok regression and Bland Altman analysis. The results showed that the PPG of the finger was destroyed in the limb movement state. There were six variables of postauricular PRV, which showed a positive linear relationship and good agreement (<i>p</i> > 0.05, ratio <math><mo>≤</mo></math>0.2) with HRV in all experiments. Our study suggests that the postauricular PPG could retain the necessary information of the pulse signal under the limb movement state and facial movement state. Therefore, postauricular PPG could be a better substitute for HRV, daily PPG detection, and mobile health than finger PPG.</p>","PeriodicalId":39637,"journal":{"name":"Journal of Medical Engineering and Technology","volume":"47 3","pages":"179-188"},"PeriodicalIF":0.0,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9735877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
News and product update. 新闻和产品更新。
Journal of Medical Engineering and Technology Pub Date : 2023-04-01 DOI: 10.1080/03091902.2023.2187166
{"title":"News and product update.","authors":"","doi":"10.1080/03091902.2023.2187166","DOIUrl":"https://doi.org/10.1080/03091902.2023.2187166","url":null,"abstract":"Manufacturers are invited to send details of new products to be included in this section. All information supplied should be strictly factual. The text may be altered by the editors. There is no charge to the manufacturers of products featured in this section and the journal accepts no responsibility for the accuracy of the information provided. Please send details to Dr J. Fenner, Associate Editor (JMET), Medical Physics (Dept. Infection, Immunity and Cardiovascular Disease), Faculty of Medicine Dentistry and Health, University of Sheffield, Beech Hill Road, Sheffield, S10 2RX, UK. E-mail: j.w.fenner@sheffield.ac.uk.","PeriodicalId":39637,"journal":{"name":"Journal of Medical Engineering and Technology","volume":"47 3","pages":"197-199"},"PeriodicalIF":0.0,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9414766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Estimation of mechanical properties by transcatheter monitoring using local impedance and contact force. 利用局部阻抗和接触力进行经导管监测的机械性能估计。
Journal of Medical Engineering and Technology Pub Date : 2023-02-01 DOI: 10.1080/03091902.2022.2134479
Sota Kawakami, Emiyu Ogawa, Hidehira Fukaya, Gen Matsuura, Sumire Aiga, Hiroshi Kumagai
{"title":"Estimation of mechanical properties by transcatheter monitoring using local impedance and contact force.","authors":"Sota Kawakami,&nbsp;Emiyu Ogawa,&nbsp;Hidehira Fukaya,&nbsp;Gen Matsuura,&nbsp;Sumire Aiga,&nbsp;Hiroshi Kumagai","doi":"10.1080/03091902.2022.2134479","DOIUrl":"https://doi.org/10.1080/03091902.2022.2134479","url":null,"abstract":"<p><p>The mechanical properties of the myocardium in the left ventricle and right atrium were estimated by simultaneously measuring the local impedance (LI) and contact force (CF) using an ablation catheter. Radiofrequency catheter ablation (RFCA) is a well-established arrhythmia treatment. Monitoring the RF power, CF and properties of myocardium during RFCA are necessary to estimate the effect of ablation. Indices, such as CF, lesion size index and ablation index, do not include the myocardium mechanical properties. Therefore, there is the risk of side effects, such as cardiac tamponade, by excessive catheter indentation into vulnerable areas. We propose the simultaneous measurement of LI and CF for estimating the myocardial mechanical properties to reduce the side effects. In this study, an <i>in vitro</i> experimental system was constructed to measure LI and CF <i>via</i> the catheter. The relationship between the porcine myocardial tissue thickness and CF-LI curve was investigated using the left ventricle and right atrium. Power function coefficients approximating the CF-LI curve increased with thicker left ventricle. The thickness of the myocardium can be estimated by simultaneously measuring LI and CF. Intraoperative measurement of the myocardial mechanical properties can be used to determine the ablation conditions at each site.</p>","PeriodicalId":39637,"journal":{"name":"Journal of Medical Engineering and Technology","volume":"47 2","pages":"141-146"},"PeriodicalIF":0.0,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10565693","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Low-cost body-powered prosthesis for transfemoral amputation. 用于经股截肢的低成本身体动力假体。
Journal of Medical Engineering and Technology Pub Date : 2023-02-01 DOI: 10.1080/03091902.2022.2134480
Obinna P Fidelis, Ayomide P Arowolo
{"title":"Low-cost body-powered prosthesis for transfemoral amputation.","authors":"Obinna P Fidelis,&nbsp;Ayomide P Arowolo","doi":"10.1080/03091902.2022.2134480","DOIUrl":"https://doi.org/10.1080/03091902.2022.2134480","url":null,"abstract":"<p><p>To allow an amputee resume healthy walking, a well-designed lower limb prosthesis is required. However, in many developing countries, the cost of high-tech and often imported prosthesis is out of the financial reach of many amputees. The objective of this study was to design and implement a mechanical, body-powered transfemoral prosthetic device to help transfemoral amputees regain functional ambulation. The materials used include socket adapter, acetone hardener, plaster of Paris bandages, perlite lining, and polyester resin. Using anthropometric measurements of a volunteer amputee, a user-friendly and ergonomic transfemoral prosthetic device was designed using AutoCAD rendering and fabricated using engineering methods such as casting and welding. The prosthetic limb consists of a polypropylene socket, a galvanised iron knee joint with a hinge and spring suspension system, and a perlite foot. An evaluation of the prosthetic limb after fabrication showed that it restores the ambulatory function of the amputee.</p>","PeriodicalId":39637,"journal":{"name":"Journal of Medical Engineering and Technology","volume":"47 2","pages":"147-152"},"PeriodicalIF":0.0,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9137385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
An automated standalone hand wash outdoor deployment unit for infectious disease control. 一种用于传染病控制的自动独立户外洗手装置。
Journal of Medical Engineering and Technology Pub Date : 2023-02-01 DOI: 10.1080/03091902.2022.2100495
Oludolapo Opeyemi Olufajo, Olufemi Ayomide Balogun
{"title":"An automated standalone hand wash outdoor deployment unit for infectious disease control.","authors":"Oludolapo Opeyemi Olufajo,&nbsp;Olufemi Ayomide Balogun","doi":"10.1080/03091902.2022.2100495","DOIUrl":"https://doi.org/10.1080/03091902.2022.2100495","url":null,"abstract":"<p><p>The recent global coronal virus pandemic raised increased awareness towards ideal hand hygiene procedures as promoted by World Health Organisation (WHO) and other related health care associations. Compliance to the prescribed procedure has been rather difficult as people gradually get accustomed to this effective hand wash habit, especially with regards the 20 s hand rub process. Traditional hand wash faucets with manual controls are prone to exposing users to recontamination or transmission of infectious deceases. Also, water wastage of 51.32% was observed from empirical studies. The designed automated standalone hand wash unit (ASHU) seeks to solve the contamination problem by running a contactless tap operation, while guiding users through the ideal hand wash procedure with the aid of visual and audio annunciators. Being a standalone unit, solar energy in used to power of the low power design system for uninterrupted outdoor operation, even in unelectrified rural regions. With the suitable level sensors and IoT infrastructure put in place, the unit maintenance operators are able to monitor the fluid levels in with the aid of a custom-built mobile app. Subsequently, the ASHU yields a water wastage potential of only a maximum of 13.31% and a user satisfaction guarantee for 93% of the refill cycle.</p>","PeriodicalId":39637,"journal":{"name":"Journal of Medical Engineering and Technology","volume":"47 2","pages":"104-120"},"PeriodicalIF":0.0,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9135869","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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