Control Variant Research Articles

Abstract 15609: ParSE-seq: A Calibrated Multiplexed Assay for Clinical Interpretation of Putative Splice-Altering Variants

Background: Up to 10% of disease-associated variants are predicted to affect RNA-splicing. Interpreting the clinical significance of putative splice-altering variants outside the 2-base pair canonical splice sites remains difficult without functional studies. Goal: To develop a calibrated, high-throughput assay to adjudicate variant effects on RNA splicing. Methods: We established Parallel Splice Effect Sequencing (ParSE-seq), a multiplexed minigene assay, to test variant effects on RNA splicing quantified by high-throughput sequencing. We used the tool SpliceAI to prioritize exonic and intronic candidate splice variants, and ClinVar to select curated benign and pathogenic controls in SCN5A , which encodes the major voltage-gated cardiac sodium channel. We transfected 271 barcoded minigene constructs into HEK cells or induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs), and calibrated to the American College of Medical Genetics and Genomics scheme. Variants were interpreted using the calibrated functional data, and experimental data correlated to SpliceAI predictions. We studied selected variants by automated patch clamp (APC) in HEK cells and by assessing splicing and channel function directly in CRISPR-edited iPSC-CMs. Results: ParSE-seq revealed the splicing effect of 245 SCN5A variants in iPSC-CMs. The assay had concordant scores for 43/45 benign and pathogenic control variants, achieving both PS3- and BS3-strong levels of evidence after calibration. 41/114 exonic variants and 30/66 intronic variants with determinate scores disrupted splicing. 9 of 42 Variants of Uncertain Significance were reclassified, and 30 of 34 variants with conflicting interpretations were reinterpreted using the functional data. Predictions from SpliceAI performed well on experimental data (AUC = 0.96). We identified 3 clinically relevant splice-altering missense variants that had normal function when tested with a cDNA-based APC assay. A splice-altering intronic variant, c.1891-5C>G also disrupted splicing and sodium channel electrophysiology when introduced into iPSC-CMs by CRISPR-editing. Conclusions: ParSE-seq is an efficient, calibrated, high-throughput assay to facilitate splice-altering variant interpretation.

Implementation of Nonlinear Controller to Improve DC Microgrid Stability: A Comparative Analysis of Sliding Mode Control Variants

Electricity generation from sustainable renewable energy sources is constantly accelerating due to a rapid increase in demand from consumers. This requires an effective energy management and control system to fulfil the power demand without compromising the system’s performance. For this application, a nonlinear barrier sliding mode controller (BSMC) for a microgrid formed with PV, a fuel cell and an energy storage system comprising a battery and supercapacitor working in grid-connected mode is implemented. The advantages of the BSMC are twofold: The sliding surface oscillates in the close vicinity of zero by adapting an optimal gain value to ensure the smooth tracking of power to its references without overestimating the gains. Secondly, it exhibits a noticeable robustness to variations and disturbance, which is the bottleneck of the problem in a grid-connected mode. The stability of the presented controllers was analyzed with the Lyapunov stability criterion. Moreover, a comparison of the BSMC with sliding mode and supertwisting sliding mode controllers was carried out in MATLAB/Simulink (2020b) with real PV experimental data. The results and the numerical analysis verify the effectiveness of the BSMC in regulating the DC bus voltage in the presence of an external disturbance under varying conventional load and environmental conditions.

Role of miRNA Let-7 in Plasma of Rheumatoid Arthritis.

Objectives: Micro ribonucleic acids (miRNAs) are noncoding RNAs, recently implicated as potential biomarkers or therapeutic targets for autoimmune diseases such as rheumatoid arthritis (RA). The aim of this study is to assess the role of miRNA Let-7 in the plasma of RA. Materials and methods: Trained medical staff already enrolled for the study collected blood samples from healthy controls (N = 42) and RA patients (N = 44). In the laboratory, these samples were centrifuged at 2000 rpm for 8 minutes to separate serum from the sample, which was then transferred to a plain vial. Until transport to the genetic lab, samples were stored at -20°C Deoxyribonucleic acid (DNA) was isolated using a standard protocol cohort of controls and patient blood samples. Quantification of DNA was conducted using ultraviolet (UV) spectroscopy, and DNA quality was assessed on 0.8% agarose gel. A comparison of genotype frequencies in the different study groups was performed using the Chi-squared test, while a comparison of allelic frequencies was conducted using Fisher's exact test. Results: Variations of alleles, such as 16539423 (G>T), 16539433 (T>G), and 16539629 (A>T) were found only in RA patients. On the other hand, 16539617 (T>A), 16539622 (G>T), and 16539624 (T>C) were found only in control cases. Five sequences (three RA variants and two control variants) with minimal alignment were compared to the wild-type sequence. We found that the sequence modification of pre-miRNA 16539623 del G was significantly higher and had a risk allele in the study group [odds ratio (OR) = 3.29]. Conclusion: Rheumatoid arthritis (RA) is an autoimmune disorder that presents with a variety of clinical manifestations. Genetic factors possibly account for about 60% of disease susceptibility and expression, thus playing a very important role in disease pathogenesis. How to cite this article: Gauri LA, Liyakat N, Dadhich D, et al. Role of miRNA Let-7 in Plasma of Rheumatoid Arthritis. J Assoc Physicians India 2023;71(11):50-52.

Estimation of Heterotrophic Soil Respiration Response to the Summer Precipitation Regime and Different Depths of Snow Cover in a Temperate Continental Climate

Regime of precipitation and temperature conditions are key factors that regulate the rate of decomposition of soil organic matter in terrestrial ecosystems. The aim of this work was to assess the effect of the duration of dry periods in summer and different depths of snow cover in winter on heterotrophic soil respiration. The studies were carried out as part of a 2–year field manipulation experiment organized on gray soil (Haplic Luvisol) in the temperate continental climate conditions (southern Moscow region). Three variants were organized: (1) simulation of mild weather with uniform watering of the soil in summer and the absence of freezing in winter, (2) simulating two summer dry periods lasting 1–2 months with natural winter snow cover, (3) simulation of extreme weather with one long (~3 months) dry period in summer and complete removal of snow cover in winter. Heterotrophic soil respiration was measured by the closed chamber method on bare fallow during 2 years of continuous experiment and 1 more year after its completion. Medians of heterotrophic soil respiration for the entire period of the experiment in the three above–mentioned variants of the experiment were 38, 27 and 19 mg C/(m2 h), respectively. Two short dry periods led to an increase in heterotrophic soil respiration by 7–10%, which is associated both with the drying and rewetting cycles of the soil and with an increase in the average summer temperature of a 20–cm soil profile by 1.5°C. The prolonged dry period caused a decrease in heterotrophic soil respiration by 12–16% as a result of low soil moisture. Soil freezing led to a strong decrease in winter CO2 emission from soil, which reached 34–55% in the control variant and 57–72% when the snow cover was removed. The frost period (November–March) contributed from 25–34% without of soil freezing to 14–19% when its presence to the annual CO2 flux. We conclude that the change in the winter temperature regime of the soil due to manipulations with the snow depth led to a more significant change in the annual heterotrophic soil respiration than the lack of precipitations in the summer season.

The fungicides effectiveness in soybean cultivation under irrigation in the conditions of the Central Caucasus

Studies conducted in 2018-2020 allowed us to determine the best protection system and biological effectiveness of fungicides when growing soybeans under irrigation in the conditions of the Central Caucasus. Soybeans were grown on ordinary chernozem after winter wheat on the basis of LLC "Agrosakhar" (Izobilnensky district, Stavropol Territory). Irrigation was carried out by sprinkling. Phytoexpertize of soybean seeds before sowing revealed the presence of infection represented by fungi from the genera: Alternaria, Ascochyta, Fusarium, Peronospora, Sclerotinia, Septoria, and bacteria from the genera: Xanthomonas, Pseudomonas. Fungicides were used for seed etching: Maxim, KS; Delit Pro, KS; TMTD, VSK; Protect,KS. During the budding phase, the crops were treated with fungicides Optimo, CS and Acanto Plus, CS. The maximum effectiveness in the fight against fusarium was established when seeds were treated with the fungicide Delit Pro, CS (0.5 l /t) – the prevalence of fusarium decreased by 82.0, and the development of the disease by 70.4%. The fungicide Acanto Plus, CS (0.6 l/ha) was more effective compared to the standard by an average of 5.7–12.4%. Combined application of seed pickling Divides Pro, CS (0.5 l /t), and the treatment of crops in the budding phase with the fungicide Acanto Plus, CS (0.6 l /ha) was characterized by the greatest effect: the number of plants affected by peronosporosis decreased by 84.3% and the development of the disease decreased by 81.2%. The greatest biological effect in the fight against soybean bacteriosis was after seed etching with TMTD, VSK (6 l/t) and treatment of vegetative plants with Acanto Plus fungicide, CS (0.6 l/ha), the prevalence of bacteriosis decreased by 69.4%, and development - by 39.8%. In this variant, the highest yield of soybean seeds was obtained at 3.36 t/ha, which is more than the control variant by 0.64 t/ha and more than the standard by 0.11 t/ha. The profitability of growing soybean seeds using the studied protection systems, depending on the fungicides used, varied from 89.7 (Protect, CS (2.0 l/t); Optimo, CS (0.5 l/ha)) up to 103.4% (TMTD, VSK (6.0 l/t); Acanto Plus, CS (0.6 l/ha)).

Development of the potato cryocollection preserved in the VIR cryobank

Background. The article presents the results of the studies carried out within the framework of a complex program for the long-term conservation of genotyped accessions of domestic potato cultivars in the cryobank of the N.I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR). These accessions are genetically identical to the nomenclature standards of the corresponding cultivars.Materials and methods. The research material included 24 accessions from the in vitro collection of VIR, corresponding to the nomenclature standards of Russian potato cultivars developed in different breeding centers of the Russian Federation. Cryopreservation was carried out using the droplet vitrification method, several stages of which were modified in the Department of Biotechnology of VIR.Results and discussion. The frequency of post-cryogenic regeneration for the analyzed 24 cultivars in control variants with short-term immersion of explants in liquid nitrogen varied from 20 to 47.3%, and in 9 accessions it exceeded 39% – the current level of reliable long-term preservation of samples in cryobanks. The data of the statistical analysis failed to reveal a significant effect of the genotype or the calendar dates of different experiment replications on the regeneration ability. These 24 accessions were added to the potato cryocollection stored in the VIR cryobank. An analysis of the composition and structure of VIR’s potato cryocollection, which currently includes 140 accessions, is presented.

The content and composition of organic matter of sod-podzolic soil when applying fertilizer mixtures based on sewage sludge

Relevance. The organic matter of the soils of the Non-Chernozem zone requires additional sources of its replenishment, which can include sewage sludge (SS). The paper investigates the use of sewage sludge from Tver, introduced fresh into a mixture with additional organic substrates (sawdust, peat, straw) in the field crop rotation link.Methods. The experiment was carried out in the Tver region on sod-podzolic sandy loam soil in fourfold repetition. OSV was introduced as part of a total dose of a fertilizer mixture of 60 t/ha with additional organic substrates (sawdust, peat, straw) taken in different proportions (1:1, 1:2, 1:3) at the beginning of the experiment. The area of the experimental plot is 6 m2. Crops of the crop rotation link — mixture vetch and oat, winter rye, spring barley. The content of organic matter, its group and fractional composition were determined in soil samples according to the methods generally accepted in agrochemistry.Results. The introduction of SS together with additional substrates contributed to an increase in the amount of soil organic matter (1,38–1,5%) and its maintenance in the aftereffect at the level of 1,33–1,49%, in the control variant this indicator was 1,26% (the significance of differences p < 0,05). The studied fertilizers provided an increase in the share of GA-1 and a decrease in FA-1a. In comparison with the finished compost, fertilizer mixtures, in which the components were in equal proportions, were ahead of the comparison options in their effect. They also contributed to the highest increase in productivity of the crop rotation link among all the variants of the experiment (an increase in control — 61,1–68,2%). Compost provided an increase in productivity by only 37,9%.

Reinforcement learning with model-based feedforward inputs for robotic table tennis

We rethink the traditional reinforcement learning approach, which is based on optimizing over feedback policies, and propose a new framework that optimizes over feedforward inputs instead. This not only mitigates the risk of destabilizing the system during training but also reduces the bulk of the learning to a supervised learning task. As a result, efficient and well-understood supervised learning techniques can be applied and are tuned using a validation data set. The labels are generated with a variant of iterative learning control, which also includes prior knowledge about the underlying dynamics. Our framework is applied for intercepting and returning ping-pong balls that are played to a four-degrees-of-freedom robotic arm in real-world experiments. The robot arm is driven by pneumatic artificial muscles, which makes the control and learning tasks challenging. We highlight the potential of our framework by comparing it to a reinforcement learning approach that optimizes over feedback policies. We find that our framework achieves a higher success rate for the returns (100% vs. 96%, on 107 consecutive trials, see https://youtu.be/kR9jowEH7PY) while requiring only about one tenth of the samples during training. We also find that our approach is able to deal with a variant of different incoming trajectories.

Effect of different stand densities on xylem and phloem formation in Norway spruce plantations

Summary Preliminary results of an investigation of the thinning effect on Norway spruce tree growth in terms of xylogenesis and phloemogenesis are presented. Three plots were selected where the stand densities were reduced by pre-commercial thinning to 1800 trees/ha (plot A; mild thinning) and 1300 trees/ha (plot C; heavy thinning) in February 2020. Plot B had no silvicultural intervention and represented a control variant (4500 trees/ha). Three dominant 14-year-old Norway spruce trees were sampled (micro-cored) for studying the xylem and phloem formation in the 2020 growing season. The total differentiation duration was determined to be around 169.7 ± 12.7–179.3 ± 4.0 days. The average number of xylem cells formed in control plot B was only 140 mature cells, plots C and A were determined to have 175 and 200 mature cells, respectively. Plot A had the fastest growth rate of all the plots studied. In all three plots (A, B, C), the beginning of the early phloem, late phloem sieve cells, and axial parenchyma cells coincided. Nonetheless, in terms of total phloem cell increase, plot C displayed the fastest growth rate among the three plots studied. The first results showed that the rate of total increment in both xylem and phloem cells, as well as the total number of produced tracheids and sieve cells, seem to be positively affected after the thinning application.

Effect of Different ET-Based Irrigation Scheduling on Grain Yield and Water Use Efficiency of Drip Irrigated Maize

The development of irrigation schedules based on water balance implies a study of daily plant water requirements. A properly selected irrigation method is also of most importance. The objective of this study was to find out how surface drip irrigation (SDI) and shallow subsurface drip irrigation (SSDI), as well as different ET-based irrigation scheduling for maize (reference evapotranspiration (ETo), pan evaporation (Eo), and local climatic coefficients (lc)), affect grain yield, water use efficiency (WUE), and yield response factor (Ky) of maize. The field experiments were conducted in Vojvodina, a northern part of the Republic of Serbia, on the calcareous gleyic chernozem soil, using a complete block design in three replicates in 2019–2021. The water balance method was used for irrigation scheduling. The nonirrigated treatment was used as a control. The yield in irrigation conditions was statistically higher as compared with the nonirrigated control variant. Concerning the tested parameters, especially the maize yield, reference evapotranspiration (ETo) should be recommended as the most acceptable method for assessing maize evapotranspiration. Preference should be given to SSDI compared to SDI because the installation of laterals can be performed together with the sowing, which can ensure the uniform and timely emergence of plants. Based on the Ky coefficient of 0.71, it can be concluded that maize is moderately tolerant to water stress in Vojvodina’s temperate climate. The results can contribute to precise planning and efficient irrigation of maize in the region, implying high and stable yields.

The not-so-micro effects of in-furrow micro-dams and cover crops on water and sediment retention in potato fields

Potatoes are well-known as an erosion-prone crop due to their peculiar field structure with deeply incised furrows between the cultivated ridges. Several mitigation measures, such as cover crops and micro-dams, are available to reduce surface runoff and sediment yield in potato fields. However, quantifications of their effectiveness in reducing runoff and sediment yield are relatively scarce in Austria or the Pannonian Region. In this study, we measured runoff and erosion to quantify the effects of three mitigation measures in potatoes on soil water content (SWC), surface runoff, and sediment yield on an event basis and for the study period of three years. The tested measures included furrow cover crops, micro-dams, and a combination. In total, we observed 13 erosive events. SWC within the furrows significantly increased between 6.5% and 11% when micro-dam variants were applied compared to the control and cover crop variants. Runoff was reduced by up to 68% with cover crops and 95% on micro-dam variants, especially when combining micro-dams and cover crops. Likewise, sediment yield was reduced to approximately 50% when cover crops were used. Micro-dam variants decreased sediment loss on average by 85%. An additional crop cover on the micro-dams resulted in even higher effectiveness for reducing sediment yield (−95%) for heavy rainfall than the control variant (91.6 mm 15-min−1). While a cover crop reduces the sediment connectivity of a field, micro-dams and micro-dams supported with cover crops also reduce the runoff connectivity. A conceptual mean event shows the disconnecting effect of micro-dams on surface runoff in response to rainfall. At the same time, cover crops reduce surface runoff but do not disconnect runoff from rainfall.

Действие иловых отложений и удобрений на рост и развитие яровой пшеницы

The influence of silt deposits in combination with organic and mineral fertilizers was assessed by the growth functions and development of spring wheat of the "Madam" variety, the timing of its maturation and yield. The variants with the introduction of 30 t/ha of cattle manure, the use of 30 t/ha of silt, as well as a combined variant with the use of 10 t/ha of cattle manure with a dosage of silt deposits of 25 t/ha of silt and a background dose of mineral fertilizers were noted as the best in terms of the dynamics of the phases of development. The highest yield of spring wheat was obtained on the variant with the use of 30 t/ha of cattle manure. The excess of the control variant was 138.2%. Keywords: SILT DEPOSITS, ORGANIC AND MINERAL FERTILIZERS, SPRING WHEAT, YIELD

Primary complex motor stereotypies are associated with de novo damaging DNA coding mutations that identify KDM5B as a risk gene.

Motor stereotypies are common in children with autism spectrum disorder (ASD), intellectual disability, or sensory deprivation, as well as in typically developing children ("primary" stereotypies, pCMS). The precise pathophysiological mechanism for motor stereotypies is unknown, although genetic etiologies have been suggested. In this study, we perform whole-exome DNA sequencing in 129 parent-child trios with pCMS and 853 control trios (118 cases and 750 controls after quality control). We report an increased rate of de novo predicted-damaging DNA coding variants in pCMS versus controls, identifying KDM5B as a high-confidence risk gene and estimating 184 genes conferring risk. Genes harboring de novo damaging variants in pCMS probands show significant overlap with those in Tourette syndrome, ASD, and those in ASD probands with high versus low stereotypy scores. An exploratory analysis of these pCMS gene expression patterns finds clustering within the cortex and striatum during early mid-fetal development. Exploratory gene ontology and network analyses highlight functional convergence in calcium ion transport, demethylation, cell signaling, cell cycle and development. Continued sequencing of pCMS trios will identify additional risk genes and provide greater insights into biological mechanisms of stereotypies across diagnostic boundaries.

Effectiveness of the Use of Vermicompost Larvae of the Black Lion Fly (<i>Hermetia illucens</i>) when Germinating Seeds of Leguminous Crops

The most promising and popular insect in the field of organic waste processing is the black lion fly (Hermetia illucens), whose larvae are unpretentious in food and growing conditions. As a feed, most types of organic waste are suitable for them, which, after being digested by the larva, are enriched with various nutrients and microorganisms useful for the growth and development of plants. Larval excrement is a valuable and environmentally friendly organic fertilizer (biohumus) for growing plants. In order to test the effectiveness of the effect of biohumus of black lion larvae on the process of seed germination in laboratory conditions, liquid extracts of biohumus were obtained by extraction with distilled water and compounds of potassium hydroxide (KOH) and sodium pyrophosphate (Na4P2O7). The most effective extraction method turned out to be the method of treatment with alkali and sodium pyrophosphate, in which the most concentrated extract with a concentration of 2.44% was obtained. All types of extracts of vermicompost have been biotested for germination of seeds of seed peas (Pisum sativum L.) and white lupin (Lupinus albus L.). Compared with the indicators of the control variants with distilled water, all extracts of vermicompost had a stimulating effect on seed germination, accelerating their growth and development. The highest rates were observed in solutions of alkaline pyrophosphate extract with a pH value of 6.7–6.8 at concentrations of 0.01 and 0.05%.

The effect of the basic tillage system on soybean weediness in the right-bank Forest-Steppe of Ukraine

Goal. To improve the system of soybean crops weed control under different methods of tillage.
 Methods. Field and laboratory experiment, mathematical and statistical method to assess the reliability of the obtained results.
 Results. The researched species composition of weeds in soybean crops included 12 species of 7 families, with a predominance of dicotyledonous species (80.1—93.3%), regardless of the tillage method the proportion of the monocotyledonous species made up 6.7—19.9%. The following species were most common: Chenopodium album L., Amaranthus retroflexus L., Polygonum lapathifolia L., Galinsoga parviflora Cav., Echinochloa crus-galli (L.) Pal. Beauv. and Setaria glauca (L.) Pal. Beauv. The maximum weediness of soybean crops before herbicides application was observed under the moldboardless main tillage use (to a depth of 10—12 cm) and amounted to 481.5 pcs./m2, of which dicotyledonous species made up 81.7% and monocots — 18.3%. The lowest number of weeds (at the level of 254 pcs./m2) was observed under the No-till technology, the share of dicot species made up 80.1%. With the use of the moldboard tillage in soybean crops before herbicides use, the total number of weeds was 425.5 pcs./ m2, where annual dicotyledonous species predominated (93.3%). Soybean crops subject to herbicides use on the moldboard tillage variant formed a 2.49 t/ha yield, which was 50% higher than that of the weeded control variant. The use of the moldboardless tillage and No-till technology ensured productivity in the range of 2.34—2.40 t/ ha.
 Conclusions. Regardless of the soil tillage method, dicotyledonous weed species occupied from 80.1 to 93.3% of the soybean crops, with the predominance of Chenopodium album L., the share of which was 66.6—77.3% and Polygonum lapathifoliа L. — 17.6—24.9%. The use of various methods of soil tillage and weed control ensures elimination of weeds at the level of 91.0—91.5% and maintaining productivity in the range of 45—50%.

Influence of organic-mineral and biological fertilizers on the yield of winter garlic (Allium sativum) under the conditions of their application by drip irrigation

The article presents the results of three-year studies of the impact of the biological preparation Organic-Balance and organo-mineral fertilizer Helprost with Liposam adhesive on the sowing area of garlic of the winter variety Prometheus. It was established that under the conditions of drip irrigation and fertilization with the biological preparation Organic-Balance, organo-mineral fertilizer Helprost and adhesive Liposam with the rate of 2/2/1 l/ha in the phase of intensive growth and development of winter garlic plants were higher than the control variant by 39.4% and 37.3%, the area of the leaf blade is 280.5 cm2 and 252.7 cm2. In the first version, where the plants were watered only with water, the height was 57.4 cm, the area of the assimilation surface was 183.5 cm2. After fertilizing with organo-mineral fertilizer Helprost and adhesive Liposam at the rate of 2/1 and 1/1 l/ha, garlic plants were higher than the control variant by 37.9% and 36.4%, the leaf surface area was 224.0 cm2 and 199.6 cm2 respectively. When fed with the biological preparation Organic-balance and Liposam adhesive with a rate of 2/1 l/ha, the increase in plant height compared to the control was higher by 38.2%, the area of the leaves was 236.5 cm2. The conducted studies show a significant effect of feeding with biopreparations and organic-mineral fertilizers on crop formation. Thus, the best indicator was noted in the case of simultaneous treatment of single-toothed crops with the biological preparation Organic-Balance and organo-mineral fertilizer Helprost with the adhesive Liposam with the rate of 2/2/1 l/ha and with the rate of 2/1/1 l/ha, the yield was the highest 18, 7 and 18.3 t/ha, the yield premium was 6.5 and 6.1 t/ha, respectively. Somewhat lower indicators were obtained for feeding with the biological preparation Organic-balance, but it exceeded the control variant by 5.2 t/ha. When fertilizing with organo-mineral fertilizer Helprost with Lyposam adhesive, higher productivity indicators were obtained in the version with the rate of its application of 2/1 l/ha and prevailed over the control by 2.6%, while when fertilizing with the rate of 1/1 l/ha l/ha supplement to the harvest was 1.9%.

Effect of organosilicon adsorbent on the content of mobile forms of heavy metals and growth of test-crop under conditions of soil contamination with lead and copper

The pollution of soil by heavy metals becomes a prime ecological problem. Recultivation of polluted soil objects is usually made by means of different types of sorbents. So, in this connection the search for the most effective and multifunctional sorbing agent is relevant. The model experiment of soil pollution by several heavy metals in upper soil horizon was carried out. The soil for that research was Grey-Luvic Phaeozems. Lead (Pb2+) and copper (Cu2+) were chosen as pollutants. Solutions of lead acetate (Pb(CH₃COO)₂·3H2O) and copper sulphate (CuSO₄·7Н2O) of three different concentrations (1 MPC, 5 MPC, 10 MPC) were used as pollutants. Solutions of organosilicon adsorbent – 1,1,3,3,3-tetrahydroxy-1,3-dimethyldisiloxane polyhydrate (PMSPG) were also applied in three different variants: 0.01%; 0.1%; 1%. The mobile forms of heavy metals were researched by method of atomic absorption spectrometry. The mobile forms of heavy metals were extracted by the ammonium acetate buffer (pH = 4.8). According to results, the application of organosilicon sorbent had a positive issue. Application of adsorbent significantly reduced the concentrations of mobile heavy metal compounds. The application of PMSPG solution with concentration of 1% was the most effective. A vegetation experiment was carried out. Cress (Lepidium sativum L.) of “Zabava” variety was used as a test-crop. Favourable changes in the growth of cress with the use of adsorbent at the concentration of 1% compared to the control variants were revealed.

Влияние хелатных микроудобрений на интенсивность набухания и прорастания семян зернового сорго

The results of three-year studies in 2020-2023 have shown the prospects of processing seeds of grain sorghum varieties with solutions of chelated micronutrients that contribute to the activation of physiological and biochemical processes at the initial stages of swelling and germination of grains. There was a tendency to increase the swelling of seeds during 2 days of the experiment on average in varieties under the action of chelated micronutrients: with the use of Reasil Forte Carb-Ca/Mg/B Amino up to 67.7%, and Reasil micro Amino Zn – up to 67.5%, which is higher than the control variant (66.3%). The most responsive varieties for the use of the studied micronutrients were the Bachelor varieties, the seed germination energy of which increased by 9.7%-15.4% compared to the control variant, the Garant variety – 9.2-15.0%, the RSK Cascade variety – 8.5-11.6%. A significant increase in the length of seedlings and roots of grain sorghum varieties was revealed as a result of soaking seeds in solutions of chelated micronutrients before the experiment. The individual reaction of each variety to the use of chelated micronutrients in seed treatment has also been determined. The varieties Bachelor, Assistant, Guarantor, RSC Cascade, RSC Locus, Pendant and Prince, when treating seeds with Reasil Forte Carb-Ca/Mg/B Amino, significantly increased the length of seedlings compared to the control variant - by 10.6–21.8%. The drug Reasil micro Amino Zn caused the formation of sorghum seedlings of greater length than in the control in the varieties Magister, Assistant, Garant and RSC Cascade, the excess of the control variant was 10.0-28.1%. The greatest positive response to the use of chelated micronutrients was distinguished by the Assistant variety, which, as a result of seed treatment with these preparations, revealed an increase in the length of primary seedlings and roots greater than the control variant by 20.5–28.1%, respectively. Keywords: GRAIN SORGHUM, VARIETY, CHELATED FERTILIZERS, SEED SWELLING, GERMINATION ENERGY, EVALUATION OF PRIMARY SPROUTS

Creation of a Photobioreactor for the Effective Growth of Chlorella and Study of the Effect of the Spectral Composition of Light on Its Biomass

Chlorella is a green eukaryotic microalga (Chlorella vulgaris). The microscopic cell is spherical, 2–10 μm in diameter. This microalga is one of the most important and promising for biomass production. Chlorella is cultivated in ponds or bioreactors with specified parameters that create favorable conditions for the growth of chlorella biomass. Each set of conditions creates the opportunities for changing the growth rate and output of individual products. Two strains of chlorella were the object of the study: 1 – chlorella with a thin cell wall (Chlorella vulgaris VKPM Al-24); 2 – chlorella with a thick cell wall (Chlorella vulgaris Beijer). The culture of chlorella was cultivated on modified Tamiya nutrient medium, at 24°C and 24-hour illumination. It was cultivated for 5 days in 1000 ml flasks, in opaque grow boxes with different lighting regimes. The control variant was grown in a light room with white fluorescent lamps with an intensity of 150 μmol/m2 s, and the culture was also grown in the dark. Laboratory experiments studying the effect of spectral composition of light on growth of two strains of chlorella culture allowed identifying some regularities: 1 – the largest increase in biomass is observed when using white fluorescent lamps (T = 2700K); 2 – in the case of using FR>R or FR=R, their inhibitory effect on the growth of the studied strains of chlorella was observed. In addition, similar results were obtained when determining the optical density of the cultures, suggesting that the chlorella strains studied are similarly responsive to the action of different spectral compositions of light. Analyzing the absorption spectrum, it should be noted that it has a continuous character. It has been experimentally established that the first maximum is located in the red region (660 to 690 nm) and the second in the blue region (430 to 450 nm). The minimum absorption is observed in the green light region (500 to 610 nm).

Study of the Antimicrobial Properties of Compositions Based on Essential Oils From Eucalyptus and Thuja Plants With White Naphthalan Oil

Cosmetic and medical oils have been widely used in medicine and cosmetology for many years. The main function of medical oils is to be a carrier in medicinal preparations. But in many cases, they perform a therapeutic function at the same time. It should be noted that for obtaining medical and cosmetic oils, low-sulfur and low-paraffin oils are more appropriate. In the context of the conducted research, the antimicrobial activity of various combinations of essential oils obtained from eucalyptus and thuja plants with therapeutic white naphthalan oil taken as a control variant was studied to clarify the effective bactericidal action mechanism. In the preparation of these compositions were prepared with the addition of therapeutic white naphthalan oil as the main component, and in addition, essential oil separated from eucalyptus and thuja plants in the ratio of 1:0,04:0,08:0,1 was analyzed for their antimicrobial effects on 4 microbes (Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, Candida albicans). Medicinal and cosmetic products were determined according to the received antimicrobial effective compositions.