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.

With the increasing application of wireless technologies in crop production, the question whether radiofrequency (RF) electromagnetic fields (EMF) influence crops becomes significant. Effects of RF EMF on plants were studied at genetic, physiological, morphological, anatomical levels, and the obtained results were contradictory. EMF could affect plant growth, biomass accumulation and metabolite synthesis, and thus the quality and quantity of the crop yield. The aim of this study was to examine long-term effects of EMF emitted by wireless sensors used in precision agriculture on economically important wheat and maize varieties, during the sensitive early period of crop development. We investigated morphological (growth rate, biomass) and physiological characteristics (photosynthetic pigments, reducing sugars, anthocyanins and malondialdehyde) 10 days after 2-hour irradiation of sprouts with 900 MHz 370 V/m continuous electromagnetic wave. None of the examined parameters displayed statistically significant difference between control and exposed plants. We concluded that the 900 MHz EMF is safe for crops subjected to precision agriculture technologies even at strong electric field exposures for two hours.

The growing use of wireless communication devices has been significantly increasing the level of high frequency electromagnetic fields (EMFs) in the environment, which raises a concern for possible deleterious effects on living organisms. Long lasting exposure to low-intensity EMFs can cause effects on the molecular and cellular level, and a number of morphological and physiological changes. The aim of this work was to investigate the effects of 2.41 GHz EMF emitted by wireless communication systems on human erythrocytes after in vitro irradiation. The amount of the hemoglobin released from the cells was measured as an indicator for membrane destabilization. Effects of different exposure times (20 min or 4 h) and time elapsed after exposure to 2.41 GHz pulsed or continuous EMFs with different intensities, emitted from a textile (0.213–0.238 V/m) or a dipole (5, 20, 40 and 180 V/m) antenna, were investigated. The obtained results showed that the low intensity EMF had no significant effect on the hemoglobin release from irradiated cells; even a slight tendency for membrane stabilization was noticed 3–4 hours after the end of 20-min exposure to 0.213–0.238 V/m, 2.41 GHz EMF. There was no difference in the effects of continuous and pulsed EMFs. Increased hemoglobin release was observed only during the 4-hour exposure to 180 V/m, 2.41 GHz continuous EMF. Under these conditions, the temperature of the cell suspension had been rising, so we compared the results obtained under EMF with the effects of conventional heating. Moreover, after 1-hour exposure to 180 V/m the released hemoglobin level was a bit higher than the control one but the difference disappears within an hour after terminating the irradiation. In conclusion, the in vitro exposure to 2.41 GHz EMF emitted by wireless communication devices with power density below the reference level for population exposure does not change the stability of the cell membrane of human erythrocytes.

Smart agriculture technology is rapidly spreading for its economic benefits and increase in farming efficiency. The management of agricultural activities is fulfilled by a network of connected devices and sensors, using wireless technologies and software to exchange data over the Internet. The electromagnetic fields (EMFs) these systems use increase the background level in farmlands, and the crop plants are exposed to unusual levels of unnatural, polarized, coherent, and variable EM radiation. This combination determines EMF influence on plants. Many studies found effects at different levels of organization—molecular, organismal, and even ecosystem levels—but the underlying mechanisms are still not well understood. In this review paper, we attempted to clarify possible mechanisms on the very basic molecular level involved in the realization of biological effects, discussing the interaction of EMFs with water molecules in living systems, from their effects on biologically significant molecules, membranes, ion channels, and ion transport, oxidative processes in cells, and photosynthesis to the effects on plant growth and development. In conclusion, we discuss the obstacles to defining the conditions for the manifestation of beneficial or adverse effects and setting exposure limits.

Spent brewer’s yeast, a major by-product of the brewing industry, is a valuable source of bioactive compounds. The main technological limitation for their recovery is the rigid yeast cell wall, while the high nucleic acid content may restrict the direct use of yeast-derived extracts for human nutrition. In this study, pulsed electric field (PEF) treatment, applied alone or in combination with enzymatic hydrolysis, was investigated for the production of yeast-derived extracts with different compositions. PEF treatment performed in continuous-flow mode resulted in more than 98% of cells with irreversibly permeabilized membranes and enabled the rapid and selective release of low-molecular-weight intracellular compounds during subsequent incubation of the cells in water. Within 4 h, approximately 61% of total antioxidant activity, 65% of glutathione, and around 80% of free α-amino nitrogen and B-group vitamins were recovered at different rates, while the aqueous extracts were characterized by low purine nucleotide content. Electropermeabilized cells exhibited high sensitivity to enzymatic hydrolysis. After 6 h of incubation with 0.2% (v/v) Alcalase, the obtained hydrolysates contained 254 ± 17 mg/g DCW of protein, mostly in the form of peptides, 148.2 ± 17.3 mg/g DCW of free α-amino nitrogen, and a total phenolic content of 16.7 ± 1.9 mg GAE/g DCW. The maximal antioxidant activity (62.7 ± 9.3 mg TE/g DCW) was reached after 4 h of incubation, corresponding to a 2.7-fold increase compared with cell lysates. Overall, PEF treatment, applied alone or in combination with enzymatic hydrolysis, provides an efficient and mild approach for the production of yeast-derived extracts with tailored compositions and potential applications in the food, pharmaceutical, and cosmetic industries.

Internet of things long range (IoT/LoRa) devices emit radiofrequency electromagnetic fields (RF-EMF), ensuring long-range, low-power communication, and their use in precision agriculture continuously expands. Thus, the interest in the impact of low-intensity but long-term EMF exposure on plants has increased. In this study, maize plants were exposed to 868 MHz, 10 mW EMF for the first 28 days of their development with soil-buried antennas. Plants were divided into three groups: Control, Sham-exposed, and EMF-exposed. Biological effects were followed on morphological, physiological, and biochemical levels every week. The plant height values were fitted to a Gompertz function modeling the growth. The results showed slightly faster early development of EMF-exposed plants in about 21 days. The relative dry-leaf biomass from EMF-affected plants was a bit higher than in the Control and Sham groups until day 21. Chlorophyll fluorescence analysis (JIP-test) indicated photosynthetic stability. Antioxidant enzyme activity, antioxidant capacity, content of malondialdehyde, hydrogen peroxide, and reducing sugars were measured, and principal component analysis was done for all parameters. Overall, the developmental stage accounts for most of the observed variations in the data rather than EMF exposure. The results suggest that under the tested conditions, IoT/LoRa-emitted EMF did not provoke adverse effects in maize and acted as a modest modulator of physiological functions.