The Lapicque equation for electrical stimulation of nerve, proposed in 1907 and further discussed in 1909, is applied to the Hodgkin-Huxley neuron, proposed in 1952 and universally recognised nowadays. We demonstrate how an analytical model of the relationship described by Lapicque can be derived through consideration of this mathematical model of the nerve membrane potential when subject to pulsed current input.
Mass is an important factor that has an influence on the stability of the human body. The hypothesis is the higher the mass, the higher the stability. The proportionality of the human body when considering body mass and physical height are expressed by the BMI (body mass index). Our goal was to verify a correlation between BMI and postural stability with the use of stabilometry tests on baropodometric platforms to confirm or refute the mentioned hypothesis. A total of 184 healthy subjects (73 females and 111 male) participated in the measurement and performed a bipedal test with their eyes open and closed, where the evaluated parameters were the confidence ellipse area and the length of the oscillation. After a statistical assessment of the measurements, we can confirm that having the eyes open or closed has an influence on the confidence ellipse area and the length of oscillation. The measured values show that the confidence ellipse area and the length of oscillation are not dependent on the BMI.
- MeSH
- index tělesné hmotnosti * MeSH
- klinická studie jako téma MeSH
- lidé MeSH
- posturální rovnováha * MeSH
- velikost těla MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
Oxygen is the most common drug used in the critical care of infants. There is significant morbidity and mortality associated with excess or inadequate levels. For this reason, an important element of many therapeutic interventions in the ICU requires assessment of their acute impact on oxygenation. It is common to normalize the arterial level of oxygen with the fraction of inspired oxygen (PF-ratio). Further, a change may often be more important than the absolute level. Though the PF-ratio is often reported, it was surmised that the rarely reported, relative magnitude of change in PF-ratio might be a useful metric for assessing the stability and effectiveness of therapy. Therefore, individual patient data from two different studies were evaluated. The cases included periods of therapeutic intervention and periods without intervention, thus permitting the evaluation of the PF-ratio's potential sensitivity to change and thresholds for relevant change. During surfactant administration in extremely preterm infants, the PF-ratio improved at least 25% in 91% of the infants, while 9% showed less than a 10% change. During high-frequency oscillatory rescue in children, the PF-ratio improved at least 25% in 76% of the infants, while 8% showed less than a 10% change. Consideration of thresholds of 50% and 5% reflected low prevalence. In periods of routine care, the prevalence of marked changes was less prevalent but still common (6% and 55%) and periods of little change more prevalent (21% and 21%). We believe this initial work supports the feasibility of using the magnitude of change in PF-ratio and provides a useful stimulus for additional evaluations.
- MeSH
- kyslík MeSH
- lidé MeSH
- oxygenoterapie * metody MeSH
- saturace kyslíkem MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
The aim of the study was to assess the interaction of the cardiostimulation system of the patient and the source of electromagnetic interference (EMI) during the patient’s work by Holter monitoring of ECG. Finally, to analyze ECG recording and evaluate possible pacemaker (PCM) program responses to the presence of EMI. The observation was performed in the selected patient with the single-chamber conventional pacemaker during practicing of a profession in an industrial environment with a real risk of interaction with the defined source of interference. The heart rhythm was monitored with a standard Holter monitor and the measurement was repeated during three work shifts. The PCM was revised before each measurement and at the same time the programming was adjusted for monitoring purposes. The ECG record was back-analyzed and the device response to the presence of EMI was evaluated. No program response to the presence of an interfering electromagnetic field (EMF) was observed from the ECG recording analysis. This program response would manifest to abnormalities in the ECG curve (asynchronous pacing, pacing inhibition, competitive pacing). There were no events in the PCM memory indicating the effect of the EMI.
- MeSH
- elektrokardiografie ambulantní metody MeSH
- elektromagnetická pole MeSH
- kardiostimulátor * MeSH
- lidé MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
Oxygen is the most common drug used in the critical care of infants. There is significant morbidity and mortality associated with excess or inadequate levels. For this reason, an important element of many therapeutic interventions in the ICU requires assessment of their acute impact on oxygenation. It is common to normalize the arterial level of oxygen with the fraction of inspired oxygen (PF-ratio). Further, a change may often be more important than the absolute level. Though the PF-ratio is often reported, it was surmised that the rarely reported, relative magnitude of change in PF-ratio might be a useful metric for assessing the stability and effectiveness of therapy. Therefore, individual patient data from two different studies were evaluated. The cases included periods of therapeutic intervention and periods without intervention, thus permitting the evaluation of the PF-ratio's potential sensitivity to change and thresholds for relevant change. During surfactant administration in extremely preterm infants, the PF-ratio improved at least 25% in 91% of the infants, while 9% showed less than a 10% change. During high-frequency oscillatory rescue in children, the PF-ratio improved at least 25% in 76% of the infants, while 8% showed less than a 10% change. Consideration of thresholds of 50% and 5% reflected low prevalence. In periods of routine care, the prevalence of marked changes was less prevalent but still common (6% and 55%) and periods of little change more prevalent (21% and 21%). We believe this initial work supports the feasibility of using the magnitude of change in PF-ratio and provides a useful stimulus for additional evaluations.
- MeSH
- hyperoxie komplikace terapie MeSH
- hypoxie komplikace terapie MeSH
- jednotky intenzivní péče o novorozence MeSH
- lidé MeSH
- novorozenci extrémně nezralí MeSH
- oxygenoterapie * metody ošetřování škodlivé účinky MeSH
- saturace kyslíkem MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- metaanalýza MeSH
- práce podpořená grantem MeSH
Knife attacks have become a global problem in recent years, especially in countries where access to firearms is limited. However, the current situation is that the method of selection and characteristics of protective equipment about the physical attributes of stabbing attacks is not systematically determined. Attacks with stab weapons can be divided according to the weapon's grip, the angle of the attack, and its execution into six different attacks (e.g., underarm action stab, overarm action stab, etc.). Our work presents a survey of methods for capturing and then evaluating the physical parameters of point attacks in specific motion capture and analysis programs. In this work, kinematic analysis was used to analyze motion during a stabbing attack and to obtain data on the kinetic energy of the stab. The measurements were performed with the MoCap system - Vicon Nexus 2.70. The results of the study show that the average value for the straight stab and the underarm stab is almost the same (66.5–67.1 J), while the overarm stab reaches a much higher value (92.8 J). The study aims to determine the kinetic energy of types of attacks, for standards state the level of protection based on energy levels. The results could provide new insights into the current state of protective equipment and energy values in national/international standards.
- MeSH
- biomechanika MeSH
- biomedicínský výzkum MeSH
- bodné rány * patologie prevence a kontrola MeSH
- kinetika MeSH
- lidé MeSH
- počítačové zpracování signálu přístrojové vybavení MeSH
- snímání pohybu * metody přístrojové vybavení MeSH
- střelné zbraně MeSH
- zbraně klasifikace MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
- přehledy MeSH
In this paper, we describe a technical design of wearable multi-sensor systems for physiological data measurement and wide medical applications, significantly impacted in telehealth. The monitors are composed of three analog front-end (AFE) devices, which assist with interfacing digital electronics to the noise-, time-sensitive physiological sensors for measuring ECG (heart-rate monitor), RR (respiration-rate monitor), SRL (skin resistivity monitor). These three types of sensors can be used separately or together and allow to determine a number of parameters for the assessment of mental and physical condition. The system is designed based on requirements for demanding environments even outside the realm of medical applications, and in accordance with Health and Safety at Work directives (89/391/CE and Seveso-II 96/82/EC) for occupational hygiene, medical, rehabilitation, sports and fitness applications.
- MeSH
- automatizované zpracování dat metody přístrojové vybavení MeSH
- biomedicínské technologie metody přístrojové vybavení MeSH
- biomedicínský výzkum MeSH
- dechová frekvence MeSH
- duševní zdraví MeSH
- elektrokardiografie metody přístrojové vybavení MeSH
- lidé MeSH
- nositelná elektronika * klasifikace MeSH
- srdeční frekvence MeSH
- telemedicína metody přístrojové vybavení MeSH
- tělesná výkonnost MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
- přehledy MeSH
The paper describes a software tool created to inspect the anatomical structures of any segmented voxel model of the human body for use in numerical analyses of the interaction of non-ionizing electromagnetic radiation with a metallic implant. A voxel model is a three-dimensional representation of the human body model in the form of a numerical array of indices that identify each element as belonging to a particular tissue, organ, or anatomical part. The process of virtual implant placement within these models while maintaining their anatomical limitations is complex and time-consuming. We have created a software tool in the MATLAB environment to simplify and speed up this process. As a representative case, we used the developed tool to identify three implantation sites of pacing electrodes within the cardiovascular system of the available AustinMan and AustinWoman models.
- MeSH
- biomedicínský výzkum MeSH
- digitální technologie metody přístrojové vybavení MeSH
- kardiostimulace umělá metody MeSH
- kardiovaskulární nemoci diagnostické zobrazování prevence a kontrola MeSH
- lidské tělo * MeSH
- modely anatomické MeSH
- počítačová simulace MeSH
- software * trendy MeSH
- Publikační typ
- práce podpořená grantem MeSH
- přehledy MeSH
Acute ischemic stroke and intracranial hemorrhages (ICH) represent critical situations for the patient. Rapid accurate diagnosis and therapy are required to prevent serious lifelong consequences or death. In the case of suspected head circulatory pathology, computed tomography (CT) is often the first choice among imaging techniques because of its availability, speed and reliability. In order to refine and speed up the diagnostic process, advanced algorithms implemented in computer aided diagnosis systems are currently being developed. This paper presents approaches to an automatic ICH localization as a part of a research project aimed at the development of machine learning methods for the analysis of circulatory disorders in head CT scans. Three designed deep learning-based algorithms are described and compared for prediction of the exact position of ICH within a 3D CT scan, and in two cases also for classification into the sub-types. An objective evaluation of the methods is presented along with a discussion of the results. Further possibilities for circulatory diseases analysis in head CT scans using modern algorithms are also discussed.
- MeSH
- biomedicínské technologie * MeSH
- biomedicínský výzkum MeSH
- intrakraniální krvácení * diagnostické zobrazování prevence a kontrola MeSH
- ischemická cévní mozková příhoda diagnostické zobrazování prevence a kontrola MeSH
- kardiovaskulární systém diagnostické zobrazování patofyziologie MeSH
- lidé MeSH
- neuronové sítě (počítačové) MeSH
- počítačová rentgenová tomografie metody přístrojové vybavení MeSH
- počítačová simulace MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
The article introduces the remote ECG data collecting system. The system consists of a one-lead ECG device connectable via USB to a smartphone, an Android application, a server, and a web application. The ECG device is designed as a USB dongle with small dimensions and uses On-the-Go (OTG) powering technique. These features classify the developed device as wearables. The measured ECG data are stored in the smartphone's internal memory and transmitted to the remote biobank server at predefined time intervals for archiving and subsequent processing. The functionality of Android and the web application are also described in the article. Both applications have a user-friendly graphical user interface. The proposed system was tested in two scenarios: ECG measured on the patient simulator and living subject. The measured raw ECG signals are suitable for basic diagnostics of cardiac health and confirmed the correct function of the proposed system.
- MeSH
- automatizované zpracování dat metody MeSH
- banky biologického materiálu MeSH
- biomedicínský výzkum MeSH
- chytrý telefon přístrojové vybavení MeSH
- elektrokardiografie * metody přístrojové vybavení MeSH
- kardiovaskulární nemoci diagnostické zobrazování patofyziologie prevence a kontrola MeSH
- mobilní aplikace klasifikace trendy MeSH
- počítače MeSH
- počítačové komunikační sítě trendy MeSH
- Publikační typ
- práce podpořená grantem MeSH
- přehledy MeSH
