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Internet examination is a new innovation in elearning. Internet examination extends the virtual mobility from the learning process to the examination of the students’ knowledge on the course topic. Internet examination has pedagogical benefits also in the case where the students are on the site of teaching. The paper is based on the experience we have obtained at the Ragnar Granit Institute.

Non-invasive blood pressure (NIBP) simulators are electro-mechanical devices used for testing and evaluating oscillometric non-invasive blood pressure monitors. Simulators are used mainly in clinical environment to assist with routine and after-repair testing of NIBP monitors. In this paper we suggest basic procedures for evaluating a NIBP simulator; assessing its suitability and quality. Proposed evaluation procedure consists of a static calibration and a dynamic evaluation. In static calibration the simulator is calibrated as a common indicating barometer. In dynamic evaluation the output waveforms are investigated (repeatability of the output according to different static pressures and heart rates, repeatability of the output at a constant blood pressure magnitude). Proposed evaluation procedure represents a minimal set of tests to ensure the simulator can be used for testing NIBP monitors. A commercial simulator SmartArm (by Clinical Dynamics, USA) was evaluated according to it and the results are presented.

An implantable surface acoustic wave (SAW) microsensor has been developed for early detection and monitoring of seizures based on local temperature changes in the brain’s epileptogenic zones that occur prior to and during an epileptic event. Three SAW sensors were designed and fabricated: a 172 MHz filter, a 434 MHz filter, and a 434 MHz delay line. Their temperature sensitivities were tested by measuring the phase change between the input and output waveforms as a function of temperature. We achieved a phase sensitivity of 144 phase degrees per °C and a minimum detectable temperature of 5 mK for the 434-MHz, 10.2-μs delay line. Based on the sensitivity tests, a prototype 434 MHz SAW sensor was fabricated to a size of 11 x 1 x 1.1 mm, which is commensurate with existing brain implantable probes. Because of possible damping of the surface waves by the surrounding tissue or fluid, a glass housing with dry air was built on the top of the SAW substrate. Test and reference sensors were used in the prototype system to minimize the effect of source instabilities and to amplify the temperature effect. The phase change between the output waveforms of the sensors was measured with phase detector electronics after they were converted to lower (10.7 MHz) frequencies by standard mixers. The complete prototype sensor was tested in a saline water bath and found to detect as low as 3 mK changes of temperature caused by the addition of hot water. Operation ability of the system in its wireless variant was demonstrated.

Conventional blood pressure measurement can not explain the link between hypertension and cardiovascular diseases. The missing link is arterial stifness wich can be meassured by noninvasive applanation tonometry. Although well known fenomenon, due to techological reasons it was not clinicaly used for diagnostic purposes. With computer and other technology we are able do detect and analize periferal pulse wave and central aortic pulse wave. Central aortic pulse wave is a function of arterial stifness. The process, by wich the arterial system interacts with left ventricle and coronary arteries can be demonstrated by analysing aortic root pressure waveform. In the young it is common to see no or small augmentation in contarst to older person. Examlpes are presented.

We evaluated the appropriateness of 24-h ambulatory blood pressure (BP) monitoring to detect prehypertensive conditions in apparently healthy siblings of patients with premature cardiovascular disease (CVD). We performed office blood pressure measurements and 24-hour ambulatory blood pressure monitoring in 30 young adults (mean age 26 ± 3 years), whose parents have experienced premature CVD, and 30 control subjects (mean age 26 ± 3 years) with a negative family history of CVD. Positive parental CVD history group had significantly higher mean values of 24-h systolic BP (123 ± 10 mm Hg vs. 118 ± 6 mm Hg; p = 0.044), daytime systolic (127 ± 12 mm Hg vs. 121 ± 7 mm Hg; p = 0.041) and diastolic BP (77 ± 8 mm Hg vs. 73 ± 4 mm Hg; p = 0.045) as well as 24-h heart rate (71 ± 8 beats/min vs. 67 ± 8 beats/min; p =0.05) and systolic BP load (21 ± 20% vs. 10 ± 11%; p = 0.02) compared to controls. There was no significant inter-group difference in blood pressure measurements obtained by conventional office method. In addition, the study group had a considerably higher diurnal variability of blood pressure and heart rate, which is believed to be contributing to their overall CVD risk. In conclusion, slightly higher levels of blood pressure, blood pressure variability and heart rate are early determinants of higher CVD risk, which can be detected in individuals by using 24-h ambulatory blood pressure monitoring.

Varieties of the oscillometric non-invasive blood pressure (NIBP) measuring devices are based on recording the arterial pressure pulsation in an inflated cuff wrapped around a limb during the cuff deflation. The recorded NIBP data contain the pressure pulses in the cuff, called oscillometric pulses, superimposed on the cuff deflation. Some of NIBP devices have also implanted microphone inside the cuff, which enables measurements of Korotkoff sounds The objectives of this contribution are, first, to extract the transfer characteristics of the oscillotonometric method of NIBP deflation from the pressure pulses, and second, to extract the Parametric coefficient of the NIBP system with regression path with ARMAX algorithm.

Contraction properties of spastic muscle has been evaluated using tensiomyographic method before and after treatment of spastic muscles with BTX-A. Significant differences are observed in TMG responses of a spastic muscle of cerebral origin before and after treatment with BTX-A. Typically, a TMG parameter Dm increases while time related TMG parameters Tr and Ts decrease after treatment of a muscle with a BTX-A. A parameter Tr/Dm has been found the most sensitive to changes of the muscle’s contractile properties. It is expected that the method can be used for determining muscle selection and therefore more effective use of expensive medicine and to evaluate the efficiency of the treatment.

Integration of home and healthcare environments and the need for precise and detailed diagnosis data are the driving forces of the recent research works in the area of wireless medical devices. The aim of this paper is to make a comparative analysis on various research works done in this sector in the last couple of years and suggest some approaches for the design of a portable, power efficient, affordable and ergonomic system with the assurance of quick and reliable response. We focus on the relative-discussion on various biosignal analysis methods, circuit design, microcontrollers, wireless communication protocols on the basis of performance, reliability, size and cost regarding the design of a telediagnosis system. Though we have limited this paper on the ECG analysis only, the proposed hardware can be extended anytime for monitoring other biosignals.

The paper presents application of time-gated, intensified CCD camera for imaging of local changes of absorption in the non-homogenous liquid phantom. The surface of the phantom was illuminated sequentially at 25 points (forming 5×5 array) by laser beam at wavelength of 780 nm generated by picosecond, near-infrared diode laser. The spatial distribution of diffusely reflected photons was measured in reflectance geometry at null source-detector separation. For each position of the laser beam the reflectance was measured for two different time windows, distinctly delayed in respect to the laser pulse. The observation of late photons, which penetrated deeply in the optically turbid medium allowed to image the absorbing inclusion (10 mm diameter black ball) located at depth of 15 mm. For each of two time windows the single images for all scanned points were summed. Obtained final images allowed to localize the non-homogeneity in the phantom. The study shows, that the presented method based on imaging at null source-detector separation distance for late time windows may be applied in the evaluation of the tissue absorption measurements, especially in the brain oxygenation imaging.

The impact of various shaped endotracheal tubes on ventilation parameters has been preliminary assessed in this study. Two uncuffed pediatric tubes of different designs: a standard tube (cylindrical) and a new tube of smooth cone shape (3, 3.5 and 4 mm ID) have been examined under IPPV mode ventilation and using infant lung model. The total inspiratory flow resistance (R_i), peak inspiratory preassure (PIP) and work of breathing (WOB) have been determined under intubation with the standard and the cone shaped tube, and also for non-intubated infant lung model. The significant reduction of the Ri, PIP and WOB has been received when the standard tube had been changed with the new cone tube. The results have been confirmed in a case clinic study.