Assessment of Electromagnetic Field Exposure on European Roads: A Comprehensive In Situ Measurement Campaign.

The rapid evolution of wireless communication technologies (such as fifth-generation (5G) cellular networks) in the last years has allowed connecting different objects (from wearable electronics to vehicles) and people through communication networks, and at the same time, has led to widespread deployment of base stations. Along with this growth, questions about the potential adverse effects on human health due to electromagnetic fields (EMFs) from base station antennas have also been raised. In this paper, we focus on the assessment of EMFs in automobiles during short (between cities) and long (between countries) trips on several European roads. Comprehensive measurement campaigns were carried out in several European countries: Austria, Bulgaria, Croatia, Hungary, Italy, Slovenia, and the Republic of Serbia. The results show that the median total electric field is 0.23-0.24 V/m in Bulgaria, Croatia, Hungary, Italy, and the Republic of Serbia. In Austria and Slovenia, the median is 0.28-0.31 V/m. Austria demonstrated the highest value for the total electric field, at 17.4 V/m.

Use of a novel indentometer to evaluate skin stiffness in healthy and diseased human skin.

BACKGROUND: Mechanical behavior of the skin can be evaluated by different non-invasive methods. In this study, we applied a new measurement device based on indentometry to determine the skin mechanical properties in healthy individuals and in patients with systemic sclerosis (SSc). MATERIAL AND METHODS: Three studies were performed. Study 1 included 100 healthy individuals (46 male and 54 female) divided into four age groups with mean ages of 21.5, 28.9, 51.2, and 69.3 years, respectively. Test sites were located on the center of the forehead and the middle of both volar forearms. Study 2 included 16 healthy individuals (two males and 14 females). Test sites were on both volar forearms. Measurements were made before and after the application of Vaseline and emulsion with 12% urea. Study 3 included 20 patients (one male and 19 females) with SSc and 60 age-matched healthy individuals (23 males and 37 females). Test sites were on the center of the forehead and the middle of both volar forearms. Skin stiffness was measured with skin Indentometer IDM 800 (Courage + Khazaka, Cologne, Germany) equipped with two probes with pin diameters of 3 and 5 mm, respectively. The stiffer the skin, the less deep the displacement by the indenter. The smaller the diameter, the deeper the pin will go into the skin when using the same force. In addition, the Corneometer CM 820 (Courage + Khazaka) was used to determine epidermal water content in study 2. RESULTS: Indentometric (IDM) values of healthy subjects measured with both probes were lower on the forehead compared to volar forearms. There was no significant difference between both forearms. In all age groups, the IDM values on the male forearms were lower than on the female forearms whereas there was no significant difference on the forehead. In both sex and on all test locations a significant positive correlation between age and IDM values measured with both probes was observed. There was a significant positive correlation between IDM values measured with both probes. The application of moisturizers induced significant changes in epidermal water content whereas the IDM values remained unchanged. At both the forehead and volar forearms, the IDM values in patients with SSc were significantly lower compared to the healthy control skin. CONCLUSION: The non-invasive indentometric method used can successfully distinguish the changes in normal skin mechanical properties related to age, sex, and anatomical location, as well as in patients with SSc. The method is not appropriate to study the changes related to epidermal hydration.

A Flexible Miniature Antenna for Body-Worn Devices: Design and Transmission Performance.

The last few years have seen a rapid increase in body-worn devices because these devices cover a broad spectrum of potential uses. Moreover, body-worn devices still require improvements in their flexibility, size, and weight that necessitate the development of flexible and miniature antennas. In this paper, we present a new flexible miniature antenna for body-worn devices. To ensure flexibility and comfort when the antenna is in contact with the human body, a substrate from natural rubber filled with TiO2 is developed. The miniaturization is achieved using the quadratic Koch curve. The antenna design, optimization, and characterization are performed on a human body model. The performance of the antenna is analyzed in two scenarios: (1) in- to on-body, and (2) on- to off-body wireless communications. The results show that the antenna realized the maximum telemetry range of more than 80 mm for in-body communications and more than 2 m for off-body communications. Moreover, the highest 10 g specific absorption rate value was 0.62 W/kg. These results, in addition to the antenna's compact dimensions (12 mm × 26 mm × 2.5 mm) and the low manufacturing price, make the proposed antenna an ideal candidate for health telemetry applications.

Wearable Antennas for Sensor Networks and IoT Applications: Evaluation of SAR and Biological Effects.

In recent years, there has been a rapid development in the wearable industry. The growing number of wearables has led to the demand for new lightweight, flexible wearable antennas. In order to be applicable in IoT wearable devices, the antennas must meet certain electrical, mechanical, manufacturing, and safety requirements (e.g., specific absorption rate (SAR) below worldwide limits). However, the assessment of SAR does not provide information on the mechanisms of interaction between low-intensity electromagnetic fields emitted by wearable antennas and the human body. In this paper, we presented a detailed investigation of the SAR induced in erythrocyte suspensions from a fully textile wearable antenna at realistic (net input power 6.3 mW) and conservative (net input power 450 mW) conditions at 2.41 GHz, as well as results from in vitro experiments on the stability of human erythrocyte membranes at both exposure conditions. The detailed investigation showed that the 1 g average SARs were 0.5758 W/kg and 41.13 W/kg, respectively. Results from the in vitro experiments demonstrated that the short-term (20 min) irradiation of erythrocyte membranes in the reactive near-field of the wearable antenna at 6.3 mW input power had a stabilizing effect. Long-term exposure (120 min) had a destabilizing effect on the erythrocyte membrane.

Fully Textile Dual-Band Logo Antenna for IoT Wearable Devices.

In recent years, the interest in the Internet of Things (IoT) has been growing because this technology bridges the gap between the physical and virtual world, by connecting different objects and people through communication networks, in order to improve the quality of life. New IoT wearable devices require new types of antennas with unique shapes, made on unconventional substrates, which can be unobtrusively integrated into clothes and accessories. In this paper, we propose a fully textile dual-band logo antenna integrated with a reflector for application in IoT wearable devices. The proposed antenna's radiating elements have been shaped to mimic the logo of South-West University "Neofit Rilski" for an unobtrusive integration in accessories. A reflector has been mounted on the opposite side of the textile substrate to reduce the radiation from the wearable antenna and improve its robustness against the loading effect from nearby objects. Two antenna prototypes were fabricated and tested in free space as well as on three different objects (human body, notebook, and laptop). Moreover, in the two frequency ranges of interest a radiation efficiency of 25-38% and 62-90% was achieved. Moreover, due to the reflector, the maximum local specific-absorption rate, which averaged over 10 g mass in the human-body phantom, was found to be equal to 0.5182 W/kg at 2.4 GHz and 0.16379 W/kg at 5.47 GHz. Additionally, the results from the performed measurement-campaign collecting received the signal-strength indicator and packet loss for an off-body scenario in real-world use, demonstrating that the backpack-integrated antenna prototype can form high-quality off-body communication channels.

Use of a novel Indentometer to evaluate skin induration in localized scleroderma and psoriasis vulgaris.

INTRODUCTION: Diseased skin in localized scleroderma (LS) and plaque psoriasis (PPs) is characterized by induration that can be evaluated by non-invasive bioengineering methods. In this study, we applied a new measurement device based on indentometry to determine the changes of skin mechanical properties in patients with LS and PPs. MATERIAL AND METHODS: A total of 30 sclerodermatous plaques in 12 patients with LS and 46 psoriatic plaques in 19 patients with PPs were measured with Indentometer IDM 800 (Courage + Khazaka, Cologne, Germany). The device measures the penetration depth of the probe indenter (pin) into the skin in mm. We used two probes with pin diameters 3 and 5 mm, respectively. The stiffer the skin, the less deep is the displacement by the indenter. The smaller the diameter, the deeper the pin will go into the skin when using the same force. The measurements were made on diseased skin and in adjacent normal skin served as control. In addition, the psoriatic plaques were measured before and after treatment. RESULTS: The sclerodermatous skin and the psoriatic skin showed lower Indentometer values compared to adjacent normal skin as measured with both probes. This suggests that diseased skin is stiffer than healthy skin. The values of psoriatic plaques increased after treatment applied that correlates with the clinical improvement. The Indentometric readings significantly negatively correlated with clinical scores of skin induration. There was a significant correlation between the measurements with probe 3 mm and probe 5 mm. CONCLUSION: The non-invasive method used is appropriate for objective and quantitative determination of the degree of skin induration in LS and PPs as well as for assessment of the disease evaluation and treatment efficacy.

Application of a novel finger temperature device in the assessment of subjects with Raynaud's phenomenon.

INTRODUCTION: Finger skin thermometry is one of the most commonly used methods for evaluating the response of the digital vessels to cold stimulation. The aim of this study was to evaluate the applicability of a novel finger skin temperature device for performing cold-stimulation test (CST) in subjects with primary and secondary Raynaud's phenomenon (RP). METHODOLOGY: A total of 155 consecutive subjects were studied. They were divided into three groups: 73 patients with primary RP (8 males, 65 females, mean age 38.5 ± 16.2), 42 patients with secondary RP (4 males, 38 females, mean age 49.6 ± 13.1, connected with lupus erythematosus and systemic scleroderma), and 40 healthy controls (5 males, 35 females, mean age 38.8 ± 16.6). Standardized CST consisting of exposure of both hands to water with a temperature of 10℃ for 5 minutes was performed. Changes in skin temperature of both wrists and 2-5 fingers were measured using a novel finger temperature device (Courage & Khazaka). Measurements were made before and 5, 10, 15, 20, 25, and 30 minutes after cold stimulation. The time of recovery for baseline temperature of all fingers below 15 minutes was considered normal. RESULTS: The CST was normal in 6 (8.2%) of the patients with primary RP, in 7 (16.6%) of the patients with secondary RP, and in 28 (70%) of the healthy control subjects. The time of complete recovery of baseline temperature with respect to the first finger and for all 2-5 fingers in the three groups was as follows: 24.8 and 28.5 minutes (primary RP), 21.7 and 26.8 minutes (secondary RP), and 11.1 and 15.2 minutes (healthy subjects). Furthermore, the microcirculation was seriously disturbed (rewarming time >31 minutes of all 2-5 digits of both hands) in 54.1% (n = 79), 34.5% (n = 29) and 5% (n = 4) in the same study groups. DISCUSSION: Our results suggested that skin microcirculation is more disturbed in patients with primary RP than in patients with secondary RP. In support of this unexpected finding were the results reported by Ruaro B. et al (2019). They investigated the blood perfusion (BP) by laser speckle contrast analysis (LASCA) at different skin areas of hands and found that it was significantly lower in primary RP than in secondary RP related to systemic sclerosis. CONCLUSION: The new finger temperature device used could be considered useful for performing cold-stimulation test in patients with Raynaud's phenomenon.

Small Antennas for Wearable Sensor Networks: Impact of the Electromagnetic Properties of the Textiles on Antenna Performance.

The rapid development of wearable wireless sensor networks (W-WSNs) has created high demand for small and flexible antennas. In this paper, we present small, flexible, low-profile, light-weight all-textile antennas for application in W-WSNs and investigate the impact of the textile materials on the antenna performance. A step-by-step procedure for design, fabrication and measurement of small wearable backed antennas for application in W-WSNs is also suggested. Based on the procedure, an antenna on a denim substrate is designed as a benchmark. It demonstrates very small dimensions and a low-profile, all while achieving a bandwidth (|S11| < -6 dB) of 285 MHz from 2.266 to 2.551 GHz, radiation efficiency more than 12% in free space and more than 6% on the phantom. Also, the peak 10 g average SAR is 0.15 W/kg. The performance of the prototype of the proposed antenna was also evaluated using an active test. To investigate the impact of the textile materials on the antenna performance, the antenna geometry was studied on cotton, polyamide-elastane and polyester substrates. It has been observed that the lower the loss tangent of the substrate material, the narrower the bandwidth. Moreover, the higher the loss tangent of the substrate, the lower the radiation efficiency and SAR.

Implementation of Instrument Based on Eight Health Related Quality of Life Domains for Measuring of Willingness to Pay for Psoriasis Treatment.

BACKGROUND: Psoriasis vulgaris (PsV) is a chronic skin condition that has a major impact on health-related quality of life (HRQOL). AIM: To determine the individual burden of PsV on HRQOL using willingness to pay (WTP) instrument. MATERIALS AND METHODS: Fifty-one consecutive PsV patients were asked to evaluate their overall health and psoriasis affected health by visual analogue scale (VAS), and interviewed on 8 domains (physical, emotional, sleep, work, social, self-care, intimacy, and concentration) of HRQOL and WTP for a hypothetical cure in each domain. Two additional questions proposing 6 alternatives for therapy were also asked. The analysis is performed with descriptive and frequency statistics, Mann-Whitney and Kruskal-Wallis tests. RESULTS: The domains ranked highly were: physical comfort (90%), social comfort (77%), emotional health (75%) and work (53%). The following tendencies concerning WTP for top four impacted domains were found: the median WTP were the highest in the top impacted domains; the younger patients were willing to pay more than the older ones; the highest median WTP amounts appear in the lowest income group; the highest median WTP is associated with smaller psoriasis affected health VAS scores. The largest proportion and number of patients (37.3%, n=19) stated preferences for the systemic therapy. The second preferred choice was the thalassotherapy (29.4%, n=15). CONCLUSIONS: The utility and reliability of the instrument based on the assessment of WTP stated preferences for 8 domains of HRQOL for evaluation the individual burden of psoriasis were strongly supported.

The Effect of Educational Intervention on the Patient's Willingness to Carry out the Immunochemical Faecal Occult Blood Test for Colorectal Cancer.

BACKGROUND: There is now compelling evidence that screening for colorectal cancer may result in significantly reduced mortality. Screening tests for colorectal cancer are not systematically performed in Bulgaria. AIM: This article explores the effect of an educational intervention on the willingness of patients to participate in the screening for colorectal cancer with the immunochemical faecal occult blood test in the home setting. MATERIALS AND METHODS: A before-after design study of the effects of educational intervention comprising distribution of a brochure and one-to-one discussion with a GP. A self-administered, original questionnaire was administered before and after the intervention to 600 randomly selected patients in 40 general practices (15 patients per practice) in Plovdiv district. RESULTS: The intervention led to an increase with >20% of the patient's knowledge of the importance of the test and on how to carry out the test. Statistical analysis indicated that there was an increase in knowledge after the educational intervention about the usefulness of the test (24.8% in males, 18.3% in females) and its performance (22.7% in males, 25.4% in females). CONCLUSION: The educational intervention has significantly influenced the patient's awareness about the test's usefulness and its self-administration. It improved the awareness by providing an easy access to information, thus fostering the active involvement of the patients. A strength of the intervention was the patient-centered approach in providing additional information through one-to-one discussions, and it ensured a higher quality of the preventive screening in the general practice.

Quantitative analysis of heart sounds and systolic heart murmurs using wavelet transform and AR modeling.

A quantitative approach integrating AR modeling and wavelet transform is presented in this paper to analyze the digitized phonocardiogram. The recognition of the first and the second heart sounds (S(1) and S(2)) were facilitated with wavelet transform without referring to the QRS waveform. We found that the Daubechies wavelet is most effective in identifying S(1) and S(2). In addition, the boundaries of S(1), S(2), and the onset and duration of the systolic murmur thus identified within the systole could be marked using the wavelet-filtered signal's strength. Furthermore, quantitative measures derived from a 2(nd) order AR model were used to delineate the configuration and pitch of the systolic murmur found within through piecewise segmentation. The proposed approach was tested and proved effective in delineating a set of clinically diagnosed systolic murmurs. The suggested AR and wavelet transform combined approach can be generalized with minor adjustments to delineate diastolic murmurs as well.