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Abstract The two-spotted spider mite (TSSM), Tetranychus urticae, is among the most destructive piercing-sucking herbivores, infesting more than 1100 plant species, including numerous greenhouse and open-field crops of significant economic importance. Its prolific fecundity and short life cycle contribute to the development of resistance to pesticides. However, effective resistance loci in plants are still unknown. To advance research on plant-mite interactions and identify genes contributing to plant immunity against TSSM, efficient methods are required to screen large, genetically diverse populations. In this study, we propose an analytical pipeline utilizing high-resolution imaging of infested leaves and an artificial intelligence-based computer program, MITESPOTTER, for the precise analysis of plant susceptibility. Our system accurately identifies and quantifies eggs, feces and damaged areas on leaves without expert intervention. Evaluation of 14 TSSM-infested Arabidopsis thaliana ecotypes originating from diverse global locations revealed significant variations in symptom quantity and distribution across leaf surfaces. This analytical pipeline can be adapted to various pest and host species, facilitating diverse experiments with large specimen numbers, including screening mutagenized plant populations or phenotyping polymorphic plant populations for genetic association studies. We anticipate that such methods will expedite the identification of loci crucial for breeding TSSM-resistant plants.

Abstract Background MicroRNAs (miRNAs) are a class of endogenous noncoding RNAs that play a pivotal role in the regulation of plant development and responses to the surrounding environment. Despite the efforts made to elucidate their function in the adaptation of plants to many abiotic and biotic stresses, their role in high light (HL) stress is still vague. HL stress often arises upon plant exposure to full sunlight. Subsequent changes in nuclear gene expression are triggered by chloroplast-derived retrograde signals. Results In this study, we show that HL is involved in miRNA-dependent regulation in Arabidopsis thaliana rosettes. Microtranscriptomic screening revealed a limited number of miRNAs reacting to HL. To explain the miRNA regulation mechanisms at the different biogenesis stages, chemical and genetic approaches were applied. First, we tested the possible role of plastoquinone (PQ) redox changes using photosynthetic electron transport chain inhibitors. The results suggest that increased primary transcript abundance (pri-miRNAs) of HL-regulated miRNAs is dependent on signals upstream of PQ. This indicates that such signals may originate from photosystem II, which is the main singlet oxygen (1O2) source. Nevertheless, no changes in pri-miRNA expression upon a dark–light shift in the conditional fluorescent (flu) mutant producing 1O2 were observed when compared to wild-type plants. Thus, we explored the 1O2 signaling pathway, which is initiated independently in HL and is related to β-carotene oxidation and production of volatile derivatives, such as β-cyclocitral (β-CC). Pri-miRNA induction by β-CC, which is a component of this 1O2 pathway, as well as an altered response in the methylene blue sensitivity 1 (mbs1) mutant support the role of 1O2 signaling in miRNA regulation. Conclusions We show that light stress triggers changes in miRNA expression. This stress response may be regulated by reactive oxygen species (ROS)-related signaling. In conclusion, our results link ROS action to miRNA biogenesis, suggesting its contribution to inconsistent pri- and mature miRNA dynamics.

Objectives According to the Organization for Economic Cooperation and Development (OECD) data, 13% of deaths recorded in the European Union in 2010 were related to coronary heart disease. The Polish Central Statistical Office data show that cardiovascular mortality in 2014 was at the level of 100.1/100 000 general population. The aim of the study was to assess the current burden of deaths due to acute myocardial infarction (AMI) with the assessment of temporal and spatial variability in the Silesian Voivodeship, Poland. Material and Methods Depersonalized data obtained from the Silesian Voivodeship Branch of the National Health Fund of Poland, based in Katowice, were used as the study material. The death rate due to acute or subsequent myocardial infarction in each of the subregions of the Silesian Voivodeship was standardized to the European Standard Population 2013. The analyses of the annual AMI death rate for 2009–2014 were performed and assigned to all the subregions of the Silesian Voivodeship, according to the patients’ domicile. Results In this study, 37.7% of the patients (N = 20 806) were females, and 30 142 healthcare services were granted to them, accounting for 36.64% of all services provided to all patients. The average patient’s age during the service provision was 66±12 years, with women being about 6.5 years older than men (70±12 years vs. 64±11 years, respectively). The standardized death rate (SDR) values in each of the 8 subregions of the Silesian Voivodeship were analyzed. In 2009–2014, a substantial decrease in the SDR was noted in 7 of them, except for the Sosnowiec subregion in which an increase in the average annual SDR value was observed. Moreover, its values were the highest in the whole Silesian Voivodeship. Conclusions The obtained results confirmed the spatial variability of mortality due to AMI in the study region. The worst situation was observed in the Sosnowiec subregion in which the number of specific deaths continuously increased, probably due to the limited availability of cardiological and invasive cardiology treatments or adverse health conditions. Int J Occup Med Environ Health. 2021;34(3):363–72

Abstract One of the most important field of interest in respect to hydrogel materials is their capability to water storage. The problem mentioned above plays an important role regarding to diffusion of fluid media containing nanoparticles, what is very useful in biomedical applications, such as artificial polymeric implants, drug delivery systems or tissue engineering. In presented work, dehydration process in hydrogels used in ophthalmology as intraocular lenses was observed. Before measurements studied materials were immersed in deionized water and saline solution to obtain equilibrium swelling state. Studies of the dehydration process were carried out by use of gravimetric analysis, Fourier-Transform Infrared and Positron Annihilation Lifetime Spectroscopy. Obtained results revealed changes in hydrogen bonding structure and free volume holes induced by saline solution ingredients.

Abstract The objective of the study was the structural analysis of the 70TeO2-5XO-10P2O5-10ZnO-5PbF2 (X = Mg, Bi2, Ti) tellurite glasses doped with ions of the rare-earth elements Er3+, based on the PALS (positron annihilation lifetime spectroscopy) method of measuring positron lifetimes. Values of positron lifetimes and the corresponding intensities may be connected with the sizes and number of structural defects, the sizes of which range from a few angstroms to a few dozen nanometers. Experimental positron lifetime spectrum revealed existence of two positron lifetime components τ 1 andτ 2. Their interpretation was based on two-state positron trapping model where the physical parameters are the positron annihilation rate and positron trapping rate.