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Iron is critically important and highly regulated trace metal in the human body. However, in its free ion form, it is known to be cytotoxic; therefore, it is bound to iron storing protein, ferritin. Ferritin is a key regulator of body iron homeostasis able to form various types of minerals depending on the tissue environment. Each mineral, e.g. magnetite, maghemite, goethite, akaganeite or hematite, present in the ferritin core carry different characteristics possibly affecting cells in the tissue. In specific cases, it can lead to disease development. Widely studied connection with neurodegenerative conditions is widely studied, including Alzheimer disease. Although the exact ferritin structure and its distribution throughout a human body are still not fully known, many studies have attempted to elucidate the mechanisms involved in its regulation and pathogenesis. In this review, we try to summarize the iron uptake into the body. Next, we discuss the known occurrence of ferritin in human tissues. Lastly, we also examine the formation of iron oxides and their involvement in brain functions.

AZO thin films sputtered at power density of 4.4 x 104 W/m2, substrate temperature of 200ºC and annealed in the forming gas at 400ºC showed a highly (002) oriented crystalline structure with the larger grains. Optimal substrate temperature could not surpass 200ºC and on the other side, an annealing temperature should be higher than 200ºC. Desired properties of AZO thin films for solar cell application - the high figure of merit (F 8 %/), low sheet resistance (Rs 10 /square) and the highest transmittance (Topt 86% ) were obtained in highly oriented AZO films prepared at high values of power density, optimal substrate and annealing temperatures. The next experiments are focusing on the incorporation of AZO films into the real thin film solar cell, on the evaluation of their behaviour and on the

Many people live under stressful conditions which has an adverse effect on their health. Human stress, especially long-term one, can lead to a serious illness. Therefore, monitoring of human stress influence can be very useful. We can monitor stress in strictly controlled laboratory conditions, but it is time-consuming and does not capture reactions, on everyday stressors or in natural environment using wearable sensors, but with limited accuracy. Therefore, we began to analyze the current state of promising wearable stress-meters and the latest advances in the record of related physiological variables. Based on these results, we present the concept of an accurate, reliable and easier to use telemedicine device for long-term monitoring of people in a real life. In our concept, we ratify with two synchronized devices, one on the finger and the second on the chest. The results will be obtained from several physiological variables including electrodermal activity, heart rate and respiration, body temperature, blood pressure and others. All these variables will be measured using a coherent multi-sensors device. Our goal is to show possibilities and trends towards the production of new telemedicine equipment and thus, opening the door to a widespread application of human stress-meters.

Currently available human stress monitoring devices are either very inaccurate or rely on a strictly controlled laboratory environment. In this paper, we present the novel concept of a practical portable device for long-term monitoring of human stress in natural environment and an algorithm for calculation of the stress phenomenon. The concept envisages two synchronized blocks measuring a wider range of physiological parameters. One device will be placed on the forearm or fingers of the non-dominant hand, the other on the chest.

Modern Holter devices are very trendy tools used in medicine, research, or sport. They monitor a variety of human physiological or pathophysiological signals. Nowadays, Holter devices have been developing very fast. New innovative products come to the market every day. They have become smaller, smarter, cheaper, have ultra-low power consumption, do not limit everyday life, and allow comfortable measurements of humans to be accomplished in a familiar and natural environment, without extreme fear from doctors. People can be informed about their health and 24/7 monitoring can sometimes easily detect specific diseases, which are normally passed during routine ambulance operation. However, there is a problem with the reliability, quality, and quantity of the collected data. In normal life, there may be a loss of signal recording, abnormal growth of artifacts, etc. At this point, there is a need for multiple sensors capturing single variables in parallel by different sensing methods to complement these methods and diminish the level of artifacts. We can also sense multiple different signals that are complementary and give us a coherent picture. In this article, we describe actual interesting multi-sensor principles on the grounds of our own long-year experiences and many experiments.

This article describes modern wireless sensor devices and their application in the measurements of the human physiology. We used our own advanced ECG Holter device and EEG helmet to record the heart and brain activity impacted by different environments, materials, colors or body positions during work. In this paper, we want to show the interactions between humans and architecture design, which modify human work performance and well-being. This paper is a conclusion of the 3 different pilot studies, where different scopes of human-space interaction were explored. In the experiments, we aimed mostly at wood materials and their beneficial effects on the nervous system. The research in its actual state is primarily focused on optimizing the methods of the ECG data analysis from our Holter device and the EEG data from helmet. Based on these data, we will improve the methodology of the experiments for the next enhanced research with aspiration to automate data analysi

Porous silicon (PSi) is a semiconductor produced by a dissolution p-type silicon wafers in hydrofluoric acid (HF) solution by applying a positive potential to a silicon electrode. We investigate the effect of etching time on morphology, structure and photoluminescence of PSi produced by a solution of hydrofluoric acid (HF) and methanol without UV irradiation. We found that surface structure depends strongly on etching time. From Fourier transform infrared spectroscopy and grazing incidence X-ray diffraction we suggest formation towards less-ordered amorphous phase of PSi. All samples reveal red-band photoluminescence. Although we observe different morphology of samples (channel-like morphology versus nanometer-sized hillocks morphology) slight effect on PL active structures (small red shift) was observed. We suggest that source of luminescence in our experiment is hydrogenated amorphous silicon structures and various HySiOx complexes. We cannot rule out the effect of SixFyO complexes. Surface morphology has small effect on photoluminescence.

The paper presents the application of natural materials, especially wood, which are relevant for human well-being in built environments of health, social, and day care facilities. These properties were tested by a complex methodology in a case study in the wooden waiting room at National Oncology Institute in Bratislava. In this space, experimental tests of physiological responses were further executed on 50 volunteers moving in the waiting room for 20 min. In this article, the EEG (electroencephalograph) (four persons) and emotions from the faces of all our volunteers before entering and after a stay in a wooden waiting room were recorded. Specifically, the ECG (electrocardiograph), heart rate (HR), and respiration activity were measured by using our own designed ECG holter (40 persons), and also blood pressure and cortisol levels were observed. The usage of wooden materials verifies their regenerative and positive impact on the human nervous system, through the appealing aesthetics (color, texture, and structures), high contact comfort, pleasant smell, possibility to regulate air humidity, volatile organic compound emissions (VOC-emissions), and acoustic well-being in the space.

This article describes successive development of electrodermal activity monitoring sensor system. Our aim is to improve existing systems to be more practical and suitable for long-term monitoring. Therefore, compared to conventional devices, our system must be easily wearable, without limiting the examined person in ordinary life, with low power consumption, battery operated and reducing the impact of negative artefacts. Specifically, we describe here three devices. The first is serving mainly to familiarize with the methodology, extensive testing and optimization of measurement parameters. Based on the obtained result, we constructed second system in form of small ring - "EDA ring". Last sensor system is developed with the effort to integrate the monitoring of electrodermal activity in e-health and smart clothes.

We studied the influence of etching time in hydrofluoric acid and methanol solution on the structure and morphology of n-type porous silicon (PSi). Dissolution of Si in the solution of hydrofluoric acid with methanol with surface oxidation occurs. All investigated samples reveal pores with increasing average size proportional to the etching time. Areic density and RMS roughness observed by scanning electron and atomic force microscopies have maximum for 10 min etching time. Additional etching time leads to slight increase in the pore size diameter and decreasing the RMS roughness of layers. All amorphous PSi samples are covered with the SiO2 layer containing probably HySiOx and SiFxHy complexes. The presence of SiH complexes leads probably to the growth of PSi layers with pores. The thickness of this layer depends on etching time and probably contains HySiOx and SiFxOy complexes.

V této práci se popisují naše počáteční experimenty ve vývoji „on-line“ senzoru na monitoring koncentrace citrátu sodného (Na3C6H2O7) v mimo mozkovém proudění krve v průběhu hemodialýzy. Přesný a rychlý monitoring by umožnil regulaci koncentrace citrátu a návrat do krevního řečiště těla v jeho původních hodnotách, tím pacienta významně méně zatíženého než v přítomnosti. Nedávno jsme se soustředili na stanovení koncentrace měřením elektrické impedance a odrazivosti ve zkoumané krvi. Našim cílem je zkoumat trendy vlivu těchto signálů na koncentraci a vyvinout vhodnou metodiku, která může být použita později v senzorech. Částečně začínáme pracovat také na citlivosti metodiky, přičemž bychom rádi výpočtem dosáhli ekvivalentní elektrický model řešení. To je založeno na elektrochemickém dvouvrstvém modelu a korespondenci s Cole-Cole grafy In this paper, we describe our initial steps in the development of online sensor to monitor the tri-sodium citrate concentration in extra-cerebral blood flow during haemodialysis. Accurate and fast monitoring would allow the regulation of the concentration of citrate returning to the human bloodstream to its original values, thereby, making the patient significantly less burdened than at present. In the early stages, we focused on the determination of concentration by measuring of electrical impedance and reflection in the collected blood. Our aim is to study the trends of influencing these signals by concentration and to develop a suitable methodology that can be used later in the sensor. In part, we begin working on the selectivity of the methodology that we would like to achieve by calculating the equivalent electrical model of the solution. It is based on the electrochemical double layer model and the corresponding Cole-Cole graphs.

In this paper, we describe an application of modern wireless sensors in monitoring of physiological parameters during interaction between humans and environment design. Our goal was not only to record these interactions but also to optimize the methodology of measurement and evaluation.

Zinc oxide (ZnO) and aluminium-doped zinc oxide (ZnO:Al) thin films were prepared by RF diode sputtering at varying deposition conditions. The effects of negative bias voltage and RF power on structural and optical properties were investigated. X-ray diffraction measurements (XRD) confirmed that both un-doped and Al-doped ZnO films are polycrystalline and have hexagonal wurtzite structure. The preferential 〈0 0 1〉 orientation and surface roughness evaluated by AFM measurements showed dependence on applied bias voltage and RF power. The sputtered ZnO and ZnO:Al films had high optical transmittance (>90%) in the wavelength range of 400–800 nm, which was not influenced by bias voltage and RF power. ZnO:Al were conductive and highly transparent. Optical band gap of un-doped and Al-doped ZnO thin films depended on negative bias and RF power and in both cases showed tendency to narrowing.

The relations between the sputtering parameters and the crystalline microstructure of ZnO thin films are presented. The energetic bombardment of substrate by neutral atoms, ions and electrons during sputtering is characterized by total energy flux density which affects the film. This parameter can be estimated by RF power, substrate bias voltage and concentration of reactive gases. Substrate temperature and total energy flux density are the major parameters which have a significant influence on ZnO thin film crystalline structure.

The paper deals with simultaneous psychological application of two biosensor probes developed by two research groups. The first biosensor “Biosense” measures human surface biopotentials (namely cardiac activity (ECG)) and physical activity (acceleration). The second sensor “EDA-ring” measures resistance of human skin, so called electro-dermal activity (EDA).

Miniaturization of biomedical sensors has increased the importance of microsystem technology in medical applications, particularly microelectronics and micromachining. This work presents a new approach to biomedical monitoring and analysis of selected human cognitive processes. The system is based on our preliminary described theory and experiments (Vavrinsky et al. 2010). We are primarily interested in biomonitoring of human cognitive processes and psychophysiological conditions of car drivers in order to enhance road safety. Actually often used method is evaluation of abnormal car driver actions (sudden changes of direction with no direction indicators or too hard cornering). Main disadvantage of such a system is that they offer no prediction. More effective are prediction systems, which offer enough reaction time before undesirable situations, and so they can minimize human error factors and improve road-traffic safety. Our present research is focused on sensing, processing and analysis of selected physiological signals for mental and medical condition recognition. They are known some studies describing interface between emotional condition and physiological responses, and we want also present some, since new ideas and research in psychological recognition and biomonitoring are very welcome. It is also proved that human decisions and reactions are affected by emotional and physical comfort. Emotional reconnoiter of a car driver conditions is influenced by many cognitive processes, such as mind organization, vigilance, planning or fatigue. Nervous and angry people can be very dangerous for traffic road safety. In our experiments, we have monitored: psycho-galvanic reflex (PGR) – skin conductivity changes, heart rate + electrocardiogram (ECG), body temperature, respiration frequency, emotions. To improve the reliability of our measurements, these parameters have been monitored often by duplicate methods, sometimes at macro level, sometimes by local microsystems technologies. In first step, we implemented our technology to the virtual reality driving simulator but preparations for real implementation have been already started, and the final car implementation will follow.

This paper explains problematic of EMG (electromyography) signal measurements. Described experiments are partition of complex project “MEDISYS” dedicated to design of modern medical equipment, consisting the latest technologies and IC. The design is based on low noise wireless measurement block (for ECG, EMG and EEG monitoring) followed by actuator block with mechanical constructions and control electronic.

This work presents differential amplifier designated as a part of modular biomedical sensor system (MBSS) used for EMG (electromyography) signal measurements. Except the standard features which characterize this type of device (high gain, low noise), some special requirements comprising very low supply voltage and low power consumption could be reached by application of the described amplifier. The amplifier provides switch-able 60/80dB gain at 15 Hz – 1kHz frequency bandwidth. A fourth order anti-aliasing filter for next processing block (AD converter) is included as well.

The achieved results have proven that the dedicated developed microelectrodes are able to sense the EDR in a very sensitive and fast way. Moreover, experiments, prior to the work presented here, prove that the achieved accuracy, input signal voltage and frequency ranges are suitable not only from biomedical monitoring point of view but also from the measurement system integration and miniaturization requirements. A non-invasive portable measurement system for the reliable and precise stress detection, based on the psycho-galvanic reflex monitoring, has been designed and developed. The system is based on an auto-balancing bridge measurement method offering digital processing and displaying of the measured data in the developed GUI operating under Windows XP platform. The measurement equipment uses microelectrodes developed for this purpose, and utilizes microcontrollers containing RF wireless communication modules to transfer data between the measurement unit and a personal computer. The complete measurement system has been designed with respect to the system accuracy, sensitivity and power management. Interesting outcome has been observed ­ the psychogalvanic reflex might be much more accurately sensed by the skin admittance phase, since this parameter reflects the human skin conductivity changes more significantly. The achieved measurement accuracy, input signal voltage and frequency ranges are suitable not only from human biomedical monitoring point of view but also from the measurement system integration and miniaturization requirements. Additionally, the proposed system is versatile and flexible, easy to be extended by other sensors' types (integrated or external with wireless communication feature) or different measurement approaches, which enables measurement of other physiologic parameters (e.g. body temperature, blood pressure, heart beat, etc.) There is no doubt that the developed measurement equipment offers new opportunities towards non-invasive wireless system for

Miniaturization of biomedical sensors has increased the importance of microsystem technology in medical applications, particularly microelectronics and micromachining. This paper presents a new approach to biomedical monitoring and analysis of selected human cognitive processes. The proposed technique measures human skin conductivity and heart rate using a dedicated measurement system which offers continuous bio-monitoring in a completely safe and non-invasive manner. This technique also has no undesired influence on natural physiological processes. The main goal is monitoring of the psycho-galvanic reflex (PGR) of the human skin that might be very useful for human stress diagnosis that is performed in different medical as well as psychological experiments.

Planar thin-film microelectrodes have been developed based on conductive and transparent thin films of ZnO:Al which are applicable in biomedicine as well as in the thin film solar cells. Nano-structuralization of their interfaces (surfaces) was carried out by the ion-sputter etching and by the photo-assisted electrodeless chemical etching. Interdigital array of microelectrodes was verified as a very useful tool for biomedical application: the monitoring of blood state or psychogalvanic reflex.

This paper presents a new approach of the noninvasive biomedical monitoring of selected psychosomatic processes. The proposed method measures human skin conductivities (psycho-galvanic reflex - PGR) using the interdigitated array (IDA) of microelectrodes as well as skin temperature, which will allow continuous monitoring and analysis of complicated physiological, pathophysiological, and therapeutic processes. The psychological test was focused on short-time stress situation with a large scale of tasks, which had the probands to do during the test. The tasks were chosen in the way to charge the same part of human brain in order to amplify the stress situation.

This paper presents a new approach of the non-invasive biomedical monitoring of selected psychosomatic processes. The proposed method measures human skin conductivities (psycho-galvanic reflex - PGR) using the interdigitated array (IDA) of microelectrodes as well as skin temperature and skin reflectance using optical spectrometer, which will allow continual monitoring and analysis of complicated physiological and therapeutic processes. The psychological test was focused on short-time stress situation with a large scale of tasks.

A study of the effect of technology parameters (sputtering power, substrate temperature and post-deposition annealing) on structural, electrical and optical properties of aluminium-doped zinc oxide (AZO) thin films was carried out. The optimal technology parameters of preparation were found to get necessary properties of AZO thin films for application in solar cells - the high figure of merit (F ges 4 %/Omega), low electrical sheet resistance (Rs les 10 Omega/square) and high optical transmittance (T ges 82%, including the glass substrate).

Transparent conductive oxide thin films (indium tin oxide, zinc oxide and Al doped zinc oxide) were prepared by RF diode sputtering. Selected properties of these films (structure, resistivity and transparency) were investigated with the aim to use them in thin film solar cells.

This paper describes a new modification of non-invasive biomedical monitoring of psychosomatic processes. The proposed method is based on skin conductivity measurements by interdigitated array (IDA) of microelectrodes, which allows continual monitoring and analyzing of complicated physiological, pathophysiological and therapeutic processes. Main goal is to monitor psycho-galvanic reflex of the human skin in medical and psychological experiments.

A novel asymmetric ratio resistance method has been developed to overcome the technological residual defects and imperfections. Accurate and reproducible monitoring of small differences of temperatures and concentrations is also important in biochemical sensors, e.g. calorimetric or electrochemical sensors. We have applied that new principle in the electrochemical conductometry method.

Following sensor system, described in this article is composed of portable units, intended for in-time wireless measurement and evaluation of electrical activity, produced by skeletal muscles. It brings a lot of advantages to biomedical electronics and medical care. In order to optimize the performance of novel proposed smart biomedical instrument we have focused on measurement of the known electromyography (EMG) signal characteristics at periodic muscle motion with constant load (physical exercise). Except for very precise measurement features, which characterize this device (high gain, low noise, wireless data transfer, multi-probe measuring), some special features as low voltage and ultra-low power consumption were reached by application of the described amplifier in order to achieve its longer performance.

The design of the car driver monitoring system is presented with a novel IDAT microsensor applied. We have developed new thin film multipurpose microsensors (IDAT) consisting of an impedance sensor based on the interdigital array of microelectrodes which is integrated together with temperature resistive sensor on single chip. The developed microsensor allows monitoring of psychogalvanic reflex, heart pulse and skin temperature using depth impedance analysis of different skin layers by choosing the appropriate size of microelectrodes.