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1.
Sensors (Basel) ; 23(13)2023 Jun 22.
Article in English | MEDLINE | ID: mdl-37447671

ABSTRACT

Artery stiffness is a risk factor for cardiovascular disease (CVD). The measurement of pulse wave velocity (PWV) between the carotid artery and the femoral artery (cfPWV) is considered the gold standard in the assessment of arterial stiffness. A relationship between cfPWV and regional PWV has not been established. The aim of this study was to evaluate the influence of gender on arterial stiffness measured centrally and regionally in the geriatric population. The central PWV was assessed by a SphygmoCor XCEL, and the regional PWV was assessed by a new device through the photoplethysmographic measurement of multi-site arterial pulse wave velocity (MPPT). The study group included 118 patients (35 males and 83 females; mean age 77.2 ± 8.1 years). Men were characterized by statistically significantly higher values of cfPWV than women (cfPWV 10.52 m/s vs. 9.36 m/s; p = 0.001). In the measurement of regional PWV values using MPPT, no such relationship was found. Gender groups did not statistically differ in the distribution of atherosclerosis risk factors. cfPWV appears to be more accurate than regional PWV in assessing arterial stiffness in the geriatric population.


Subject(s)
Pulse Wave Analysis , Vascular Stiffness , Male , Humans , Female , Aged , Aged, 80 and over , Carotid Arteries , Femoral Artery , Risk Factors
2.
Sensors (Basel) ; 23(11)2023 May 28.
Article in English | MEDLINE | ID: mdl-37299871

ABSTRACT

The area of military operations is a big challenge for medical support. A particularly important factor that allows medical services to react quickly in the case of mass casualties is the ability to rapidly evacuation of wounded soldiers from a battlefield. To meet this requirement, an effective medical evacuation system is essential. The paper presented the architecture of the electronically supported decision support system for medical evacuation during military operations. The system can also be used by other services such as police or fire service. The system meets the requirements for tactical combat casualty care procedures and is composed of following elements: measurement subsystem, data transmission subsystem and analysis and inference subsystem. The system, based on the continuous monitoring of selected soldiers' vital signs and biomedical signals, automatically proposes a medical segregation of wounded soldiers (medical triage). The information on the triage was visualized using the Headquarters Management System for medical personnel (first responders, medical officers, medical evacuation groups) and for commanders, if required. All elements of the architecture were described in the paper.


Subject(s)
Military Personnel , Wounds and Injuries , Humans , Triage/methods , Warfare , Decision Support Techniques
3.
Sensors (Basel) ; 22(23)2022 Dec 01.
Article in English | MEDLINE | ID: mdl-36502072

ABSTRACT

This article presents the Automatic Speaker Recognition System (ASR System), which successfully resolves problems such as identification within an open set of speakers and the verification of speakers in difficult recording conditions similar to telephone transmission conditions. The article provides complete information on the architecture of the various internal processing modules of the ASR System. The speaker recognition system proposed in the article, has been compared very closely to other competing systems, achieving improved speaker identification and verification results, on known certified voice dataset. The ASR System owes this to the dual use of genetic algorithms both in the feature selection process and in the optimization of the system's internal parameters. This was also influenced by the proprietary feature generation and corresponding classification process using Gaussian mixture models. This allowed the development of a system that makes an important contribution to the current state of the art in speaker recognition systems for telephone transmission applications with known speech coding standards.


Subject(s)
Speech Perception , Speech , Speech Recognition Software , Recognition, Psychology , Selection, Genetic
4.
Pol Merkur Lekarski ; 46(276): 257-262, 2019 Jun 28.
Article in Polish | MEDLINE | ID: mdl-31260435

ABSTRACT

Measurement of pulse wave velocity (PWV) is a simple and noninvasive way to assess stiffness of the arteries. PWV measurement can refer to both the aorta and peripheral arterial vessels. Currently, the most clinically significant is the measurement of PWV between the carotid artery and the femoral artery, which is defined as the speed of the aortic pulse wave. Numerous studies have demonstrated the significance of prognostic PWV aortic measurement as a recognized exponent of subclinical organ damage both among the general population as well as among patients with increased cardiovascular risk, examining patients in detail with hypertension, diabetes, chronic renal failure. The prognostic value of PWV aortic measurement was reflected in the guidelines of the European Society of Cardiology (ESC) and the European Society of Hypertension (ESH). In clinical trials, the repeatability and reproducibility of PWV measurements were also evaluated, both parameters being considered satisfactory. The paper presents reports from studies on the significance of pulse wave velocity results in the prognosis assessment in different disease entities as well as in age groups.


Subject(s)
Hypertension , Pulse Wave Analysis , Vascular Stiffness , Aorta , Carotid Arteries , Humans , Hypertension/diagnosis , Reproducibility of Results
5.
Environ Technol ; 38(1): 128-139, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27241082

ABSTRACT

In the process of electron beam flue gas treatment (EBFGT), most energy is spent on NOx removal. The dose distribution in the reactor is not uniform and the flue gas flow pattern plays an important role in the process efficiency. It was found that proper construction of the reactor may increase the energy efficiency of the process. The impact of the number of irradiation stages and mixing conditions on NOx removal efficiency was investigated for an ideal case and a practical solution was presented and compared with previously known EBFGT reactor constructions. The research was performed by means of computational fluid dynamics methods in combination with empirical Wittig formula. Two versions of dose distribution were taken for calculations. The results of the research show that for an ideal case, application of multistage irradiation and interstage mixing may reduce the energy consumption in the process by up to 39%. On the other side, simulation of reactor construction modification for two-stage irradiation results in 25% energy consumption reduction. The results of presented case study may be applied for improving the existing reactors and proper design of future installations.


Subject(s)
Air Pollutants/chemistry , Air Pollution/prevention & control , Electrons , Nitrogen Oxides/chemistry
6.
Muscle Nerve ; 46(1): 63-9, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22692996

ABSTRACT

INTRODUCTION: Electrophysiological studies of human motor units can use various electromyographic techniques. Together with the development of new techniques for analysis and processing of bioelectric signals, motor unit action potential (MUAP) wavelet analysis represents an important change in the development of electromyographic techniques. METHODS: The proposed approach involves isolating single MUAPs, computing their scalograms, taking the maximum values of the scalograms in 5 selected scales, and averaging across MUAPs to give a single five-dimensional feature vector per muscle. After Support Vector Machine analysis, the feature vector is reduced to a single decision parameter that allows the subject to be assigned to 1 of 3 groups: myogenic, healthy, or neurogenic. The software is available as freeware. RESULTS: MUAP wavelet analysis yielded consistent results for the diagnostic index and muscle classification, with only 7 incorrect classifications out of a total of 1,015 samples. CONCLUSIONS: This proposed approach provides a sensitive and reliable method for evaluating and characterizing MUAPs.


Subject(s)
Action Potentials/physiology , Electrodiagnosis/methods , Motor Neurons/physiology , Muscle, Skeletal/physiopathology , Neuromuscular Diseases/diagnosis , Electromyography , Humans , Neuromuscular Diseases/physiopathology , Wavelet Analysis
7.
Appl Radiat Isot ; 70(5): 837-47, 2012 May.
Article in English | MEDLINE | ID: mdl-22386663

ABSTRACT

The possibility of application of fluorescein and radioactive 99mTc as tracers for determination of residence time distribution of liquid phase and for diagnosing hydrodynamic conditions in apparatuses for membrane separation was studied. Two different ultrafiltration systems with diverse arrangement of liquid flow: the apparatus with helical flow generated by the movable element (inner cylinder) and the tubular module with cross flow filtration, were tested by the RTD technique. The tracer studies were supplemented with modelling. The optimal conditions enabling to handle the plug flow-like structure in the helical apparatus were determined. The minimum of dimensionless variance (vard) was obtained at P=0.765 bar, Q(R)=121.88 l/h and Ω=2887.5 rpm. In spite of higher linear velocities attained in the tubular cross-flow module, the flow structure in the helical apparatus was more similar to the ideal plug flow pattern that was demonstrated by higher Peclet numbers and lower values of the dimensionless variance. Application of movable part and Couette-Taylor flow in the membrane apparatus may balance the advantages coming from high flow rates applied in cross-flow filtration systems minimising formation of the deposit on the membrane surface and reducing membrane fouling.

8.
Comput Methods Programs Biomed ; 107(3): 393-403, 2012 Sep.
Article in English | MEDLINE | ID: mdl-21194783

ABSTRACT

This paper describes a new method for the classification of neuromuscular disorders based on the analysis of scalograms determined by the Symlet 4 wavelet technique. The approach involves isolating single motor unit action potentials (MUAPs), computing their scalograms, taking the maximum values of the scalograms in five selected scales, and averaging across MUAPs to give a single 5-dimensional feature vector per subject. After SVM analysis, the vector is reduced to a single decision parameter, called the Wavelet Index, allowing the subject to be assigned to one of three groups: myogenic, neurogenic or normal. The software implementation of the method described above created a tool supporting electromyographic (EMG) examinations. The method is characterized by a high probability for the accurate diagnosis of muscle state. The method produced 5 misclassifications out of 800 examined cases (total error of 0.6%).


Subject(s)
Action Potentials/physiology , Neuromuscular Diseases/diagnosis , Support Vector Machine , Algorithms , Computer Simulation , Electromyography/methods , Humans , Models, Statistical , Motor Neurons/physiology , Muscle, Skeletal/pathology , Neuromuscular Diseases/classification , Probability , Reproducibility of Results , Signal Processing, Computer-Assisted , Software , Time Factors
9.
Article in English | MEDLINE | ID: mdl-21096234

ABSTRACT

The paper presents a new method for neuromuscular disorders diagnosis based on analysis of scalograms determined by the Symlet 4 wavelets technique. Obtained results served for extraction of five features, which, after SVM analysis, were reduced to a single decision parameter allowing assigning the investigated cases to one of three groups: myogenic, neurogenic or normal. Software implementation of the method permitted to create a diagnostic tool for EMG investigation aid. The method characterizes high probability of accurate diagnosis of a muscle state with total error of 0.5% - 4 misclassifications out of 780 examined cases.


Subject(s)
Action Potentials/physiology , Artificial Intelligence , Electromyography/methods , Motor Neurons/physiology , Muscle Contraction/physiology , Muscle, Skeletal/physiology , Wavelet Analysis , Algorithms , Humans , Muscle, Skeletal/innervation , Pattern Recognition, Automated/methods , Reproducibility of Results , Sensitivity and Specificity
10.
Article in English | MEDLINE | ID: mdl-19162855

ABSTRACT

The paper presents a new approach to the computer aided diagnostic systems for the needs of quantitative electromyography. The approach is based on the analysis of wavelet scalograms of the motor unit action potentials calculated on the basis of 4th order Symlet wavelet. The scalograms provide the vector consisting of six features describing the state of a muscle that can be reduced to the two features with use of Linear Discriminant Analysis. Consequently, the healthy, myogenic and neurogenic cases can be successfully classified using the linear methods.


Subject(s)
Action Potentials/physiology , Algorithms , Electromyography/methods , Muscle, Skeletal/physiology , Neuromuscular Junction/physiology , Synaptic Transmission/physiology , Adolescent , Adult , Discriminant Analysis , Humans , Linear Models , Male , Young Adult
11.
Article in English | MEDLINE | ID: mdl-19162859

ABSTRACT

A method of diagnosing neural-muscular diseases via Fourier spectral analysis is presented in the paper. Application of this analysis allowed for obtaining a series of spectral features. This resulted in a selection of a discriminant ensuring the best sensitivity of the new method, better than the QEMG method used in the clinical practice. Software implementation of the spectral discriminant enabled creation of a computer diagnostic tool supporting EMG examination. The method is fully automated.


Subject(s)
Artificial Intelligence , Diagnosis, Computer-Assisted/methods , Electromyography/methods , Neuromuscular Diseases/diagnosis , Pattern Recognition, Automated/methods , Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Reproducibility of Results , Sensitivity and Specificity , Young Adult
12.
IEEE Trans Biomed Eng ; 54(12): 2300-2, 2007 Dec.
Article in English | MEDLINE | ID: mdl-18075047

ABSTRACT

The statistical processing of electromyographic signal examination performed in the time domain ensures mostly correct classification of pathology; however, because of an ambiguity of most temporal parameter definitions, a diagnosis can include a significant error that strongly depends on the neurologist's experience. Then, selected temporal parameters are determined for each run, and their mean values are calculated. In the final stage, these mean values are compared with a standard and, including additional clinical information, a diagnosis is given. An inconvenience of this procedure is high time consumption that arises from the necessity of determination of many parameters. Additionally, an ambiguity in determination of basic temporal parameters can cause doubts when parameters found by the physician are compared with standard parameters determined in other research centers. In this paper, we present a definition for spectral discriminant that directly enables a unique diagnosis to be made. An essential advantage of the suggested discriminant is a precise and algorithmically realized definition that enables an objective comparison of examination results obtained by physicians with different experiences or working in different research centers. A suggestion of the standard for selected muscle based on a population of 70 healthy cases is presented in the Results section.


Subject(s)
Action Potentials/physiology , Algorithms , Diagnosis, Computer-Assisted/methods , Electromyography/methods , Motor Neurons/physiology , Muscle, Skeletal/physiology , Neuromuscular Junction/physiology , Humans , Signal Processing, Computer-Assisted , Synaptic Transmission/physiology
13.
IEEE Trans Biomed Eng ; 51(3): 548-51, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15000388

ABSTRACT

This paper presents problems related to thermal radiation of human bodies in microwave range with respect to diagnosis of breast carcinoma. A mathematical model of thermal radiation transfer through tissues is introduced and methods of measurement of temperature, depth and size of a heat source, by means of multifrequency microwave thermograph are described. Theoretical considerations are supplemented by presentation of experimental results.


Subject(s)
Algorithms , Body Temperature/physiology , Diagnosis, Computer-Assisted/methods , Microwaves , Models, Biological , Radiometry/methods , Thermography/methods , Biomedical Engineering/methods , Computer Simulation , Diagnosis, Computer-Assisted/instrumentation , Radiometry/instrumentation , Thermography/instrumentation
14.
Neurol Neurochir Pol ; 36(1): 25-32, 2002.
Article in Polish | MEDLINE | ID: mdl-12053613

ABSTRACT

Urinary dysfunction in idiopathic Parkinson's disease (IPD) has already been described, however its incidence, urodynamic pattern, dependence on the severity of parkinsonism as well as improvement with levodopa treatment are not exactly known. The aim of the study was to evaluate the frequency of urinary disturbances in patients with idiopathic Parkinson's disease and their relationship to treatment with levodopa. The investigation was carried out on 41 IPD patients aged 37-84 (mean 61.6) years. The neurological examination, including evaluation of parkinsonism according to UP-DRS scale was conducted together with the urological tests, including uroflowmetry and cystometry. Patients with infection of the urinary tract and with prostate hypertrophy were excluded from the study. 32 (78%) patients had urinary symptoms: frequency in 27 cases (65%), urgency in 9 cases (21%), urge incontinence in 1 case and dysuria in 1 case. Disorders in urodynamic examination were found in 26 cases (63%); they were: detrusor hyperactivity in 21 cases (51%), prolonged time of micturition in 18 cases (44%) and decrease of maximum flow rate in 19 cases (46%). Detrusor hyperactivity was more frequent in patients with extended parkinsonian motor signs. The results of the examination indicate frequent urinary disturbances (70%) in IPD, which improve during treatment with increased dose of levodopa.


Subject(s)
Antiparkinson Agents/therapeutic use , Levodopa/therapeutic use , Parkinson Disease/complications , Parkinson Disease/drug therapy , Urination Disorders/etiology , Adult , Aged , Aged, 80 and over , Female , Follow-Up Studies , Humans , Male , Middle Aged , Urination Disorders/diagnosis , Urination Disorders/physiopathology , Urodynamics/drug effects
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