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Background Ventricular septal defect is the most prevalent form of congenital heart disease, occurring as isolated lesion in approximately 20% of cases and as part of more complex malformations in up to 40%. Multiple ventricular septal defects are usually associated with “Swiss Cheese” variant characterized by multiple perforations throughout the muscular septum, often involving the apical, mid-muscular, and anterior regions, which creates a complex network of left-to-right shunts that are technically difficult to identify and close individually. Presence of severe tricuspid regurgitation contributes to risks related to poor prognosis. An infant with congestive heart failure, severe tricuspid regurgitation, large left-to-right shunting and elevated right ventricular pressure requires a critical decision-making process for surgical management due to higher risks and poor outcome. Case presentation We are presenting herewith a six-month-old infant with Holt-Oram syndrome, who presented with classic signs of congestive heart failure, tachypnoea, poor weight gain and hepatomegaly, all indicative of systemic and pulmonary venous congestion. Chest x-ray and echocardiography confirmed the diagnosis. Despite aggressive medical management the patient’s condition continued to deteriorate and required surgical intervention. The traditional management paradigm for such infants involves a choice between palliative pulmonary artery banding or surgical closure. In this case, both options presented significant risks and were deemed suboptimal. Therefore, to avoid risks, we opted a minimal invasive perventricular device closure of the defects with success. Conclusions Children with severe tricuspid regurgitation, right ventricular failure, Swiss cheese morphology, multiple ventricular septal defects, genetic disorders and low weight may be considered for minimal invasive approaches including perventricular device closure of the ventricular septal defects whenever feasible to avoid operative risks and offer better outcomes.

Background Ventricular septal defect (VSD) is the most common congenital cardiac malformation, accounting for approximately 30% of congenital heart defects. Conventional surgical repair using cardiopulmonary bypass is invasive and associated with morbidities and prolonged hospital stay. With the advent of interventional approaches and availability of different occluding devices, the technique of perventricular device closure is evolving and being implemented successfully in larger groups of patients. We present herein, our initial experience of perventricular device closure for the ventricular septal defects in children to assess risks and benefits. Methods From March, 2023 to February, 2024, we have performed perventricular closure of ventricular septal defects in 13 children, under guidance of transesophageal echocardiography without cardiopulmonary bypass support. The median age at operation was 2 year (range 1.3–10 years) with the median body weight 11 kg (range 8.7–16.6 kg). Sixty-nine percent were males. The ventricular septal defect sizes ranged from 2.7 to 6 mm (mean 4.7 mm). Seven defects were perimembranous, four sub-aortic and two were muscular. One patient also underwent pulmonary artery de-banding with pulmonary artery balloon angioplasty and other one patent ductus arteriosus ligation, concomitantly. For defect closure, we used ventricular septal defect occlusion device (MemoPart™, Lepu Medical Technology Company, China) through a 3-cm skin incision in the lower- third of the sternum. The device sizes ranged from 5 to 8 mm (mean 6.9+-1.8 mm) and all patients except for two required symmetrical devices. Results All patients underwent device closure successfully. The procedural duration ranged between 32 and 52 min. None of the patients required cardiopulmonary bypass. The mean ventilation time and intensive care unit stay was 3 and 24 h, respectively. None of the patients required inotropic support or blood transfusions. Moreover, no patients developed any arrhythmias including heart block. The average length of hospital stay was 4.4 days. At the latest follow up, there were no residual shunts, conduction disturbances, device dislodgement or major aortic or tricuspid valve complications seen in any patients. There was no mortality. Conclusions Perventricular device closure of ventricular septal defects is a less invasive, extremely safe and effective method in children. It is associated with very fast recovery, shorter hospitalization time and better cosmetic incision. Moreover, it avoids cardiopulmonary bypass. The modifications and refinements in the design, material and implantation techniques will help in expanding the indications and prevent complications in the long-term.

The article presents results of research of monocultures and association of lactic-oxide bacteria, purple nonsulfur bacteria and yeast on indicators of stimulation of growth processes, nitrogen fixation and phosphate mobilization for 2 crops: one-year and longterm. The research was carried out in both laboratory and production conditions. It is shown that milk-oxide and purple nonsulfur bacteria stimulate growth processes of wheat variety Nador in aquatic culture by 20-30%, and their consortium with yeast - by 30%. In comparison with control, an increase of 3.4 t/ha in the yield of Golden Delishes apples was detected with 2fold treatment based on a consortium of lactic oxide, purple nonsulfur bacteria and sucromycetes. It was determined that all the strains of the above-mentioned groups of microorganisms studied mobilized hard-to-soluble compounds of phosphorus, and only purple nonsulfur bacteria were capable of nitrogen fixation.

The aim of the work is to study the process of membrane concentration of cottage cheese whey, using the bubbling method for decreasing polarization layer formation at the UF-membrane surface. A description of the experimental set and processing method for research results of using the method of fighting against a polarization layer in the process of membrane concentration of protein-carbohydrate milk raw materials are presented. Results of the experimental studies as to using the bubbling method for decreasing polarization layer formation in the process of membrane concentration of cottage cheese whey and its influence on concentration membranes productivity are given. Mathematical models, based on regression equations of factorial experiment with using the method of bubbling separated liquid above the membrane surface for choosing technological parameters of process of membrane concentration of cottage cheese whey, have been constructed. Graphic dependencies of the productivity of ultrafiltration polymer membranes of PAN type depending on initial pressure and temperature parameters of the process of membrane concentration are presented. Rational parameters of membrane concentration of cottage cheese whey using the method of bubbling initial raw materials by gas bubbles, directly close to the concentration membrane surface have been determined. Such parameters are: pressure – 0.4...0.5 МPа, temperature of skimmed milk – 40...50 ºС, skimmed milk bubbling frequency – 0.10...0.15 min-1, bubbling pressure must be 0.56...0.58 МPа. The expedience of using the new-method of gel-layer elimination has been established according to research results

The description of experimental set and the method of processing of the results of the study of the method of fight against formation of polarizing layer in the process of ultrafiltration concentration of skim milk raw material were presented. The results of experimental studies relative to the sparging method application for the prevention of polarizing layer in the process of membrane processing of the skim milk and its influence on the capacity of ultrafiltration membranes were offered. The mathematical models were constructed on the base of regressive equations of factorial experiment using the method of the raw material sparging above the membrane surface for selection of technological parameters of the process of ultrafiltration concentration of the skim milk. The rational working parameters of the process of ultrafiltration concentration of the skim milk using the sparging of the skim milk by the gas bubbles in the direct closeness to the membrane surface were determined. Such working parameters are: pressure– 0,4...0,5 MPa, temperature of skim milk– 40...50 ºС, frequency of sparging of skim milk– 0,10...0,15 min-1, pressure of sparging must be 0,56...0,58 MPa.

The aim of research is studying a new method for intensifying extraction of pectin substances during acid extraction of pectin-containing raw materials. The description of the experimental setup and the procedure for processing the results of the investigation of the application of a new method for intensifying the beet pulp extraction are described. The results of experimental studies on the application of a new combined mixing element for intensifying the extraction of pectin-containing raw materials (beet pulp) and its effect on quantitative and qualitative output characteristics are presented. Mathematical models are constructed on the basis of regression equations of the full factorial experiment with the use of a new method of intensifying the extraction process to select input technological parameters for the extraction of pectin substances from pectin-containing raw materials. The rational operating parameters of the process of extraction of pectin substances with the use of a new combinable stirring element are determined. Such working parameters are: the process duration is 1 ... 1.1, the temperature of the working medium is 60 ... 70 ºС, and the hydromodule is 8 ... 10. The research results can be used to study other technological parameters of the extraction process of pectin substances, as well as to develop a technological line for the production of pectin products.