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Leaf litter decomposition, a crucial component of the global carbon cycle, relies on the pivotal role played by microorganisms. However, despite their ecological importance, leaf-litter-decomposing microorganism taxonomic and functional diversity needs additional study. This study explores the taxonomic composition, dynamics, and functional role of microbial communities that decompose leaf litter of forest-forming tree species in two ecologically unique regions of Europe. Twenty-nine microbial metagenomes isolated from the leaf litter of eight forest-forming species of woody plants were investigated by Illumina technology using read- and assembly-based approaches of sequences analysis. The taxonomic structure of the microbial community varies depending on the stage of litter decomposition; however, the community's core is formed by Pseudomonas , Sphingomonas , Stenotrophomonas , and Pedobacter genera of Bacteria and by Aureobasidium , Penicillium , Venturia genera of Fungi. A comparative analysis of the taxonomic structure and composition of the microbial communities revealed that in both regions, seasonal changes in structure take place; however, there is no clear pattern in its dynamics. Functional gene analysis of MAGs revealed numerous metabolic profiles associated with leaf litter degradation. This highlights the diverse metabolic capabilities of microbial communities and their implications for ecosystem processes, including the production of volatile organic compounds (VOCs) during organic matter decomposition. This study provides important advances in understanding of ecosystem processes and the carbon cycle, underscoring the need to unravel the intricacies of microbial communities within these contexts., Competing Interests: The authors declare there are no competing interests., (©2024 Khomutovska et al.)

The decomposition of plant litter, most of which is found in forests, is an important element of the global carbon cycle, as a result of which carbon enters the atmosphere in the form of not only CO 2 but also volatile organic compounds (VOCs). Although the formation of litter is associated with autumn cooling, in the spring, there is a very intense fall of faded inflorescences of woody plants. This study examined the chemical composition of the litter and VOCs emitted from decaying inflorescences of four species of forest-forming trees: silver birch, European hornbeam, black alder and aspen. All litter emissions consisted of 291 VOCs, mainly terpenes actively participating in atmospheric processes. The detection of a number of typical mushroom metabolites, such as 1-octen-3-ol, known as "mushroom alcohol", and alkyl sulphides, suggests that inflorescence-derived VOCs are a mixture of components of plant and microbial origin. In methanol extracts of the fallen inflorescences of all types, 263 organic compounds were identified, the majority of which were related to carbohydrates. Their share in the extracts was 72-76%. In general, the composition of the extractive compounds indicates the easy availability of this material for assimilation by various types of destructors.

Background: The residues ofthyreostats must not be present in the edible animal tissues. The proposed in the EU minimum required performance limit (MPRL) in the animal tissues is 10 microg/kg. This implies the decision limit (CCalpha) and decision capability (CCbeta) of the analytical methods used for the determination of these compounds lower than 10 microg/kg., Objective: This study aimed at the development, basing on the literature data and own studies the analytical method allowing for the identification and quantification of five thyreostats: tapazole (TAP), thiouracil (TU), methylotiouracil (MTU), propylothiouracil (PTU) and phenylotiouracil (FTU)) in the bovine muscle tissue, which would meet the criteria set in the Commission Decision No 2002/657/EC., Material and Methods: The developed method used liquid chromatography-tandem mass spectrometry (LC-MS/MS). The sample was extracted and cleaned using the matrix solid-phase dispersion (MSPD) method. The LC was equipped with column Luna C18 Phenomenex. Dimetylotiouracyl was used as internal standard. The samples were fortified at levels: 5, 10 and 20 microg/kg. The method was validated according to the criteria laid down in Commission Decision No. 2002/657/EC., Results: At the levels, mean relative recoveries was in the range 90 - 109% and repeatability (CV %) was less than 10%. Decision limit (CCalpha) and detection capability (CCbeta) calculated for all thyreostats were below the recommended minimum required performance limit (MRPL) - 10 microg/kg., Conclusions: The developed and validated LC-ESI-MS/MS method allows for the identification and quantification of five thyreostats in the bovine muscle tissue in the quantities below 10 microg/kg. Analytical procedure meets the criteria of Commission Decision No 2002/657/EC.

Malachite green (MG) and leukomalachite green (LMG) are subjected to monitoring fish muscle, with a minimum required performance limit (MRPL) set 2 microg/kg. Samples were extracted with acetonitryle-buffer mixture and cleaned up on SCX solid phase extraction (SPE) column. LC separation MG and LMG was done on column Luna Phenyl-Hexyl Phenomenex. Samples were fortified with MG and LMG between 2 - 25 microg/kg. The coefficients of variation (CV%) were lower than 14% for MG and 16%for LMG. The mean recoveries were in the range 65- 83% for MG and 70- 73% for LMG. This method fulfils the criteria for identification and determination of MG andLMG residues in the samples of fish muscle.

Assessment of blood pressure values and their circadian rhythm were performed a group of adolescents with borderline hypertension and in patients with insulin dependent diabetes mellitus. Higher values of blood pressure in children with IDDM in comparison with healthy children and slighter decrease of nocturnal blood pressure in the investigated groups of adolescents were shown.

The studied group comprised 82 children with simple obesity. In the group the character and frequency of ECG changes in 12 conventional leads were analyzed. A correlation was established between the character and frequency of these changes and the degree of overweight and obesity duration. In children with simple obesity a considerable prevalence was observed of disturbances of sinus rhythm, impairment of intraventricular conduction and signs of left ventricular hypertrophy. The observed changes were more frequent in children with over 5 years of obesity duration. No correlation was demonstrated between the incidence of these changes and the degree of overweight.

In 81 children aged 0-18 years with normal body weight the serum pattern of fatty acids (FA) were determined by means of gas chromatography. The results show that of the 11 FA determined chromatographically, unsaturated and saturated fatty acids had differences in their distribution in the plasma. A certain regularity of these differences in favour of unsaturated fatty acids was observed. At the same time it was demonstrated that the mean values of unsaturated essential fatty acids (EUFA) increased with the age of a child. These results suggest that the plasma FA pattern may be a valuable supplementary source of information about lipid metabolism disturbances in children.