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Percutaneous endoscopic gastrostomy is the most common method for enteral nutrition in intensive care patients with dysphagia syndrome. The advantages of the method are the minimally invasive nature and duration of the operation, which also determines a small percentage of postoperative complications. There are many literary sources devoted to the most common complications, indications and contraindications to the procedure. The objective of the literature review was to analyze the data on the relative contraindications to percutaneous endoscopic gastrostomy and the tactics used by specialists to minimize the risks of performing surgery in this group of patients. Correction of the general condition and concomitant somatic diseases in the patient as well as a thorough risk assessment have the greatest impact on the immediate results of the operation.

Optically detectable magnetic resonance spectra were measured for ensembles of NV-centers in CVD diamonds with different 13C contents. The obtained spectra were described using a model based on the spin Hamiltonian. The magnitude of the magnetic field applied to the sample was estimated using the constructed model and experimental data. [ABSTRACT FROM AUTHOR]

In order to control pathogenic microorganisms, three polymer compositions were prepared and tested. First, a water-soluble positively charged polycomplex was synthesized via the electrostatic binding of anionic polyacrylic acid to an excess of polyethylenimine to enhance the biocidal activity of the polycation. Second, an aqueous solution of AgNO3 was added to the polycomplex, thus forming a ternary polycation-polyanion-Ag1+ complex with an additional antimicrobial effect. Third, the resulting ternary complex was subjected to UV irradiation, which ensured the conversion of Ag1+ ions into Ag nanoparticles ranging in size mainly from 10 to 20 nm. Aqueous solutions of the polymer compositions were added to suspensions of the Gram-positive bacteria S. aureus and the Gram-negative bacteria P. aeruginosa, with the following main results: (a) Upon the addition of the binary polycomplex, 30% or more of the cells survived after 20 h. (b) The ternary complex killed S. aureus bacteria but was ineffective against P. aeruginosa bacteria. (c) When the ternary complex with Ag nanoparticles was added, the percentage of surviving cells of both types did not exceed 0.03%. The obtained results are valuable for the development of antibacterial formulations. [ABSTRACT FROM AUTHOR]

The article contains the authors’ research in the field of jet propulsion systems with low energy consumption of small spacecraft of the class of nanosatellites. The paper presents a microwave ion engine with double acceleration of ionized gas in the gaps formed by the end surfaces of cylindrical resonators. The results of an experimental study of the pressure force of a jet set of ionized gas by the aerodynamic double angle method are presented. A stand for determining the power parameters of week plasmajet is presented. The design of the prototype is presented. The total energy consumption of the prototype is 5 watts, the accelerated gas flow rate is up to 200 km/s, the jet pressure force on the sensing element of the stand is 0,1 μN. The working body of the prototype is nitrogen at a pressure in a vacuum chamber of 18 Pa.

The authors continue their work in the field of calorimetric studies of the parameters of an accelerated ionized gas jet of prototypes of microwave ion micro-thrusters with an energy consumption of up to 10 watts. This paper presents an improved calorimetric method. The introduction into the design of a heat receiver in the form of a thin screen makes it possible to allocate the thermal component formed by the passage of an electric current through the plasma in the accelerating gap. Calorimetric studies of the prototype with a two-electrode accelerating system are carried out at the same accelerating voltages and power of the microwave generator and different mass gas flow rates. It is shown that at a nitrogen consumption of 5,668•10–9 kg/s, the velocity of the mixed jet (neutral gas with ionized component) of the gas was 63,75 m/s, the jet thrust is 0,36 μN. With a nitrogen consumption of 1,611•10–8 kg/s, the speed of the mixed gas jet was 47,9 m/s, the jet thrust was 0,77 μN.

Predictive models are central to many scientific disciplines and vital for informing management in a rapidly changing world. However, limited understanding of the accuracy and precision of models transferred to novel conditions (their 'transferability') undermines confidence in their predictions. Here, 50 experts identified priority knowledge gaps which, if filled, will most improve model transfers. These are summarized into six technical and six fundamental challenges, which underlie the combined need to intensify research on the determinants of ecological predictability, including species traits and data quality, and develop best practices for transferring models. Of high importance is the identification of a widely applicable set of transferability metrics, with appropriate tools to quantify the sources and impacts of prediction uncertainty under novel conditions.

Readily available processing hardware and "off-the-shelf" (OTS) simulation software has made "high fidelity" first principles models of both steady and transient states, for both axial and centrifugal industrial compressors, relatively easy to construct. These high-fidelity models are finding their way into "real-time. digital twin" performance monitors, front-end engineering design, and post-design – pre-construction compressor performance evaluation. The compressor models are useful for reliably demonstrating the compressor and – to some degree, based on the complexity of the model – process response to various operating conditions. Once the model is constructed, it is trivial to run a "what-if" analysis of compressor performance to answer questions related to (a) recommendations or validation of the recycle/vent valve size and actuation speed, (b) general piping layout and sizing around the compressor, (c) and hot gas bypass requirements, to name a few. This paper takes a practical approach in discussing the compressor and process parameters necessary for building these dynamic "high-fidelity" industrial-compressor models. We identify compressor inputs and compressor responses that are faithfully modeled by first-principle equations available in the simulation software and those that typically require a compromise between an "ab initio" and data-fitting approximation. We discuss the simulation's tendency to overstate pressure excursions during surge events and understate the compressor operation in the "stonewall" region. We also discuss using the simulator software's compressor-stage enthalpy calculations to predict and quantify the compressor train reverse rotation. We use our broad experience and understanding of the compressor operation and simulation and our experience with the AVEVA™ Dynamic-Simulation "OTS" simulation software as the basis for this discussion.

Analytical scanning and transmission electron microscopy were used to study the microstructure of Ce,Er-doped Na0.5La0.5MoO4 laser crystals. Crystals were grown by the Czochralski method from the melts with a nominal composition of Na0.5La0.5−xCexEr0.005MoO4, where x = 0.125 and 0.15, then annealed at 700 and 1000 °C in the oxidizing atmosphere. We found the secondary phase precipitation of Ce2O3 oxide in as-grown crystals, while after high-temperature annealing the CeO2 precipitated crystals are always observed. Impurity ions Ce3+ occupy the La sites, and approximately 20% of the nominal Ce content is involved in the formation of Ce oxide secondary phase precipitates. The length of CeO2 precipitated crystals ranged between 100 nm and 550 nm (average length was 200 nm) and their width was 30–70 nm. The mechanism of CeO2 formation is discussed. The orientation relationships of Na0.5La0.5−xCexEr0.005MoO4/CeO2, the degree of coherence of the interface, and the preferential directions of their growth in the matrix were established. CeO2 crystals precipitated in the matrix cause light scattering with a wavelength comparable to the size of the precipitates and lead to deterioration of optical transparency of the material.

Article is devoted to modern approaches to providing competitiveness of domestic engineering industry. In article the main tendencies in world and domestic practice are identified and used.

The aim of this study was to evaluate the effect of alpha-tocopherol acetate (ATA) on the activity of free-radical oxidation (FRO) in renal tissue and renal function in rats with experimental streptozotocin (STZ)-induced diabetes mellitus (DM). Methods and Results: Experiments were conducted on 22 male Wistar rats aged 60-100 days and weighing 250-300g. The animals were divided into two groups (Group 1 (control) and Group 2 (experimental. To induce DM, the animals were injected intraperitoneally 1ml of STZ solution in the citrate buffer at a dose of 65mg/kg. For more selective modeling of type 2 DM, the rats were previously injected with an intraperitoneal solution of cytoflavin based on a nicotinamide dose of 115mg/kg In Croup 2, ATA was administered in the period from the fifth to eighth weeks, inclusive, intragastrically through a tube at a daily dose of 300mg/kg. Experiments showed that after a 4-week course of ATA, the concentration of thiobarbiturate-reactive products in the kidney tissues of the rats in Group 2 was 5.3 times lower than in Group 1. The activity of all antioxidant enzymes did not differ between the two groups. In both groups, during all 8 weeks of the experiment, the levels of renal excretion of glucose, protein, and creatinine significantly exceeded the initial level, while the level of diuresis remained stable. Conclusion: The long-term administration of ATA in experimental streptozotocin (STZ)-induced DM is accompanied by a significant suppression of the activity of the FRO processes in the kidneys, but does not lead to an improvement in the course of DN.

Вроджена непрохідність тонкої кишки характеризується наявністю повного або часткового порушення її прохідності, що нерідко супроводжується розвитком синдрому поліорганної недостатності із залученням усіх органів і систем організму, та потребує проведення ургентного хірургічного втручання у новонародженої дитини. Своєчасне виявлення інтестинальної обструкції у новонароджених дітей є необхідною умовою, враховуючи імовірність розвитку важких ускладнень. Досягнення в хірургічному лікуванні, інтенсивній терапії та післяопераційній нутритивній підтримці за останнє десятиріччя призвели до покращення виживаності новонароджених з вродженою непрохідністю тонкої кишки, проте вона і досі пов’язана із значним рівнем захворюваності та летальності. З метою покращення результатів хірургічного лікування вродженої непрохідності тонкої кишки в усьому світі проводяться дослідження факторів, які впливають на летальність, але результати їх різняться і подекуди залишаються суперечливими. Факторами ризику смертності вважають складні вади серця, недоношеність, сепсис, пневмонії та такі хірургічні ускладнення, як синдром короткого кишечника, неспроможність анастомозу та гастродуоденальна дисфункція. У статті проведено аналіз публікацій з актуальних проблем діагностики та лікування вродженої непрохідності тонкої кишки у дітей. Розглянуто основні принципи та методи оперативних втручань окремих дитячих хірургічних клінік, а також реабілітацію дітей у післяопераційному періоді. Автори заявляють про відсутність конфлікту інтересів.

Aim. To study the effect of eplerenone on the activity of free radical oxidation and renal function in rats with experimental diabetes mellitus induced by streptozotocin.Materials and methods. Experiments were carried out on 36 male Wistar rats. Diabetes mellitus (DM) was simulated by a single intraperitoneal injection of streptozotocin at a dose of 65 mg/kg. Eplerenone was injected into the stomach at a dose of 50 mg/kg.Results. It was found that eplerenone in experimental diabetic nephropathy (DN) significantly attenuated proteinuria: the concentration of protein in the urine became 4 times lower than in untreated DN (p < 0.001). In the kidneys, eplerenone therapy normalized the structure and function of renal glomeruli and restored the podocyte number, which was reduced by 37.8% in the DN model. Free radical oxidation (FRO) in the kidneys of rats treated with eplerenone increased – the concentration of thiobarbituric acid reactive substances rose by 1.5 times (p = 0.009), and changes in the activity of antioxidant enzymes, such as superoxide dismutase (a decrease by 2.4 times, p = 0.002), catalase (an increase by 1.8 times, р < 0,001), and glutathione peroxidase (an increase by 1.5 times, р < 0.001) were observed, as opposed to the values in the controls.Conclusion. In streptozotocin-induced experimental diabetic nephropathy in rats, eplerenone had a nephroprotective effect, but increased oxidative stress in the kidneys. The increase in FRO could be determined by the nongenomic effect of aldosterone, which accumulates under conditions of prolonged mineralocorticoid receptor (MR) blockade. The nephroprotective effect of eplerenone can be associated with the weakening of the genomic effects of aldosterone, realized with the participation of MR.

We present a clinical case of urolithiasis. A patient diagnosed with stage 5 chronic kidney disease due to autosomal dominant polycystic kidney disease after bilateral nephrectomy underwent kidney transplantation with ureteral graft stenting. Two months after the operation, a stone was found in the upper third of the ureteral graft, complicated by necrosis in this area. Reconstructive plastic surgery on the ureter of the transplanted kidney with removal of the ureteral stone achieved the desired clinical effect.

Mitochondrial dysfunction and oxidative stress are strongly implicated in Parkinson's disease (PD) pathogenesis and there is evidence that mitochondrially-generated superoxide can activate NADPH oxidase 2 (NOX2). Although NOX2 has been examined in the context of PD, most attention has focused on glial NOX2, and the role of neuronal NOX2 in PD remains to be defined. Additionally, pharmacological NOX2 inhibitors have typically lacked specificity. Here we devised and validated a proximity ligation assay for NOX2 activity and demonstrated that in human PD and two animal models thereof, both neuronal and microglial NOX2 are highly active in substantia nigra under chronic conditions. However, in acute and sub-acute PD models, we observed neuronal, but not microglial NOX2 activation, suggesting that neuronal NOX2 may play a primary role in the early stages of the disease. Aberrant NOX2 activity is responsible for the formation of oxidative stress-related post-translational modifications of α-synuclein, and impaired mitochondrial protein import in vitro in primary ventral midbrain neuronal cultures and in vivo in nigrostriatal neurons in rats. In a rat model, administration of a brain-penetrant, highly specific NOX2 inhibitor prevented NOX2 activation in nigrostriatal neurons and its downstream effects in vivo, such as activation of leucine-rich repeat kinase 2 (LRRK2). We conclude that NOX2 is an important enzyme that contributes to progressive oxidative damage which in turn can lead to α-synuclein accumulation, mitochondrial protein import impairment, and LRRK2 activation. In this context, NOX2 inhibitors hold potential as a disease-modifying therapy in PD.