[Biomechanics of diabetic vitreopapillary traction syndrome]. / Biomekhanika diabeticheskogo vitreopapillyarnogo traktsionnogo sindroma.

Diabetic vitreopapillary traction syndrome (VPT) is a variant of diabetic retinopathy (DR) that can lead to vision loss in advanced stages. This review reports on the biomechanics of the vitreous in the pathogenesis of proliferative DR, in particular diabetic VPT. The article analyzes and summarizes literature data, presents the views of different authors on this problem, and provides the results of Russian and foreign scientific research on this pathology. It is concluded that further research in this area can lead to a significant improvement in the results of therapy, timely diagnosis, and preservation of vision in patients with DR.

Dataset on elemental composition of soils and plants under long-term application of mineral and organic fertilizers on gray forest soils in Vladimir region, Russia.

Long-term application of organic and mineral fertilizers can lead to changes in the elemental composition of agroecosystem components. Both the levels of nutrients and potentially toxic elements can change, as can the potential for these elements to be available to plants through changes in soil properties. Soil and plant samples of two species (pea Pisum sativum L. and oat Avena sativa L.) were collected from plots of a long-term field experiment on the application of mineral and organic fertilizers and their combinations to gray forest soils in the Vladimir region, Russia. Soil samples from the 0-20 and 20-40 cm layers were subjected to acid digestion to determine total element content. Mobile forms of elements were extracted from topsoil samples using acetate-ammonium buffer (pH 4.8). Sample preparation of pea and oat plant organs (stems, leaves, pods/ears) included sample digestion in a microwave sample digestion system ETHOS EASY (Milestone, Italy). The elemental composition of the samples was determined by inductively coupled plasma optical emission spectrometry (ICP-OES) using Agilent 5800 ICP-OES (Agilent Technologies, USA). The dataset includes concentration data for 34 elements, including rare earth elements, in these samples collected in 2021. The dataset also contains general agrochemical characteristics of soils of the experimental groups: pH of water and salt suspension, organic carbon content, mobile forms of phosphorus. The data can be valuable to researchers developing fertilizer application systems and modeling changes in the elemental composition of agroecosystems.

[Episcleral circular buckling in surgical treatment of recurrent rhegmatogenous retinal detachment after vitrectomy]. / Episkleral'noe krugovoe plombirovanie v khirurgii retsidivov regmatogennoi otsloiki setchatki na avitreal'nykh glazakh.

Despite the improvement of the surgical technique of vitreoretinal interventions, the number of recurrences of rhegmatogenous retinal detachment (RRD) remains quite high. PURPOSE: Evaluation of the effectiveness of episcleral circular buckling (ECB) in the treatment of recurrent RRD after vitrectomy due to progression of proliferative vitreoretinopathy (PVR). MATERIAL AND METHODS: The study analyzed the results of surgical treatment of 21 patients (21 eyes) with recurrent RRD after primary vitrectomy. All patients underwent standard preoperative examination including visometry, tonometry, ophthalmobiomicroscopy, and additionally, optical coherence tomography was performed to assess the involvement of the macular area; the presence of anterior proliferative vitreoretinopathy was determined by ultrasound biomicroscopy, axial eye length was measured with an optical biometer. All patients underwent ECB, in some cases combined with repeated vitreoretinal surgery. RESULTS: Preliminary results of the study showed high efficiency of ECB exclusively, as well as ECB combined with revision of the vitreal cavity in case of RRD recurrence after primary vitreoretinal surgery, which amounted to 95% after one additional operation and removal of silicone oil. CONCLUSIONS: Episcleral circular buckling in the treatment of recurrent RRD after vitreoretinal surgery is a multifunctional and safe method that allows achieving favorable functional and anatomical outcomes.

Circulating Marangoni flows within droplets in smectic films.

We present a theoretical study and numerical simulation of Marangoni convection within ellipsoidal isotropic droplets embedded in free-standing smectic films (FSSFs). The thermocapillary flows are analyzed for both isotropic droplets spontaneously formed in FSSF overheated above the bulk smectic-isotropic transition and oil lenses deposited on the surface of the smectic film. The realistic model for which the upper drop interface is free from the smectic layers, while at the lower drop surface the smectic layering persists is considered in detail. For isotropic droplets and oil lenses this leads effectively to a sticking of fluid motion at the border with a smectic shell. The above mentioned asymmetric configuration is realized experimentally when the temperature of the upper side of the film is higher than at the lower one. The full set of stationary solutions for Stokes stream functions describing the Marangoni convection flows within the ellipsoidal drops are derived analytically. The temperature distribution in the ellipsoidal drop and the surrounding air is determined in the frame of the perturbation theory. As a result, the analytical solutions for the stationary thermocapillary convection are obtained for different droplet ellipticity ratios and the heat conductivity of the liquid crystal and air. In parallel, the numerical hydrodynamic calculations of the thermocapillary motion in drops are made. Both analytical and numerical simulations predict the axially symmetric circulatory convection motion determined by the Marangoni effect at the droplet-free surface. Due to a curvature of the drop interface a temperature gradient along its free surface always exists. Thus, the thermocapillary convection within the ellipsoidal droplets in overheated FSSF is possible for the arbitrarily small Marangoni numbers. Possible experimental observations enabling the checking of our predictions are proposed.

[Modern aspects of the treatment of submacular hemorrhages secondary to macular degeneration]. / Sovremennye aspekty terapii submakulyarnykh krovoizliyanii na fone makulyarnoi degeneratsii.

Age-related macular degeneration complicated by submacular hemorrhage if not treated timely leads to permanent loss of central vision. The basis of effective therapy is its early start, dislocation of blood from central parts of the retina and blockage of neovascularization. This review examines the current methods of treatment of submacular hemorrhages, anatomical and functional outcomes, risks of postoperative complications, as well as trends in the use of combined methods of surgical intervention.

[Vitreopapillary traction syndrome in patients with proliferative diabetic retinopathy]. / Vitreopapillyarnyi traktsionnyi sindrom pri proliferativnoi diabeticheskoi retinopatii.

PURPOSE: To draw attention to characteristic features of the clinical manifestations of vitreopapillary traction syndrome (VPTS) in patients with proliferative diabetic retinopathy (PDR), to determine the role of the biomechanical factor in pathophysiology of this syndrome, and to evaluate the results of surgical treatment. MATERIAL AND METHODS: The features of clinical manifestations of VPTS of 50 patients with PDR who were treated at the ophthalmology center of the National Medical and Surgical Center named after N.I. Pirogov in the period from 2014 to 2018 were analyzed retrospectively. The preoperative study included standard ophthalmological examination methods, as well as ultrasound B-scan, computer perimetry, optical coherence tomography (OCT), fluorescence angiography (FA) in the first two years of observation. The comparison group consisted of 45 patients with PDR without signs of VPTS, who were treated in the center during the same period of time. RESULTS: The obtained results suggest that the pathophysiology of VPTS in diabetes mellitus has distinctive features and is determined by the topography of the peripapillary zone, as well as choroidal vascularization of the optic nerve head; biomechanical factor plays an important role in the formation of a fibrovascular stem (FVS) in VPTS. CONCLUSION: The results indicate that patients with VPTS have a worse prognosis for achieving best corrected visual acuity (BCVA) after surgery than patients without signs of VPTS. Correct and timely diagnosis, early treatment by vitreoretinal surgery give a greater chance of achieving higher BCVA in the postoperative period in this category of patients.

Evaluation of redox potentials of cathode materials of alkali-ion batteries using extended DFT+U+U↑↓ method: The role of interactions between the electrons with opposite spins.

Limitations of the DFT+U approach (e.g., in Dudarev's formulation) applied for accurate evaluation of redox potentials of cathode materials of alkali-ion batteries with U parameters calculated via the linear response (LR) method are discussed. In contrast to our previous studies, where redox potentials of several cathode materials have been calculated in a good agreement with experiment (e.g., NaMnO2, LiFePO4, and LiTiS2), herein, we analyze other cathode materials, such as LiNiO2 and Ni- and V-containing phosphates for which this method provides much underestimated redox voltages. We ascribe this limited predictive power of the DFT+U method, parameterized via LR, to the absence of corrections of Coulomb interactions between the electrons with opposite spins. Using the recently proposed extended DFT+U+U↑↓ functional, which includes the aforementioned corrections, we show how redox potentials of Ni- and V-based compounds could be calculated in a much better agreement with experiment, also proposing a procedure of parameterization of such calculations. Thus, our extended method allows us to calculate redox potentials of several important materials more accurately while retaining good agreement with experiment for structures where the standard DFT+U method also accurately predicts electrochemical properties.

[Effectiveness of multistage surgical treatment of advanced proliferative diabetic retinopathy complicated with primary cataract]. / Effektivnost' mnogoetapnogo khirurgicheskogo lecheniya proliferativnoi diabeticheskoi retinopatii, oslozhnennoi nachal'noi kataraktoi.

Vitreoretinal surgery (VRS) is the «gold standard¼ for surgical treatment of patients with proliferative diabetic retinopathy (PDR). However, the timing for the removal of primary cataract in this category of patients remains uncertain. PURPOSE: To evaluate the effectiveness of multistage surgical treatment of patients with advanced PDR complicated with primary cataract. MATERIAL AND METHODS: The study involved 94 cases of surgical treatment of patients with PDR and complicated primary cataract. These patients were divided into two groups depending on the treatment tactics. In the first group, patients were subjected to a two-step surgical procedure: VRS with silicone oil tamponade performed as the first step in their treatment followed by phacoemulsification, silicone oil removal, and IOL implantation, respectively, as the second step. In subgroup 1a - VRS was performed with standard pharmacological support. In subgroup 1b - intravitreal injection of angiogenesis inhibitors preceded VRS. In the second group, the first step was phacoemulsification performed simultaneously with vitreoretinal surgery with silicone oil tamponade; the second step consisted of removing silicone oil from the vitreous cavity. Subgroup 2a - surgical treatment was performed with standard pharmacological support (similar to subgroup 1a). Subgroup 2b - intravitreal injection of anti-VEGF drugs preceded VRS. RESULTS: Visual functions improved in 88.8% and 83.4% of cases in subgroups 1a and 1b, and in 51.3% and 66.7% in subgroups 2a and 2b, respectively. CONCLUSIONS: The study confirms the effectiveness of staged (multi-step) surgical treatment of patients with advanced proliferative diabetic retinopathy and complicated primary cataract. Conducting phacoemulsification sometime later along with silicone oil removal in PDR patients with preoperative intravitreal injection of angiogenesis inhibitors is a gentler approach for the anatomic structures of the eye during the first stage (VRS) and contributes to the reduction in the number of intraoperative and postoperative complications.

[Protocol of intravitreal drug delivery. Consensus of the Expert Counsil of Retina and Optic Nerve Diseases of the All-Russian Public Organasation «Association of Ophthalmologists¼]. / Protokol vypolneniya intravitreal'nogo vvedeniya lekarstvennykh preparatov. Konsensus Ekspertnogo soveta po zabolevaniyam setchatki i zritel'nogo nerva Obshcherossiiskoi obshchestvennoi organizatsii «Assotsiatsiya vrachei-oftal'mologov¼.

Intravitreal drug administration is a procedure that has become widespread in modern ophthalmology. However, there is no global consensus on certain aspects of this manipulation, and practitioners feel the need for guidelines. In the Russian Federation, until now, such a document was not available. The expert council on diseases of the retina and optic nerve of All-Russian public organization «Association of Ophthalmologists¼, with participation of invited specialists, has studied and analyzed the existing foreign guidelines for performing intravitreal injections, as well as the regulatory framework in Russia. As a result, this Protocol was developed and approved for use in the healthcare system of the Russian Federation. The document regulates the requirements for specialists and organizations, the conditions for performing the procedure and the necessary material resources and presents an algorithm for performing intravitreal drug administration, a patient examination check-list for various conditions of the procedure, as well as parameters for evaluating and monitoring the quality of the procedure.

[Changes in perfusional and morphological parameters of the macular area after silicone oil tamponade of the vitreous cavity]. / Dinamika perfuzionnykh i morfologicheskikh parametrov makulyarnoi zony pri silikonovoi tamponade vitreal'noi polosti.

PURPOSE: To compare the changes of the macular morphological and functional parameters in the postoperative period in patients with silicone oil tamponade after successful surgery of the macula-on rhegmatogenous retinal detachment (RRD). MATERIAL AND METHODS: The study included 20 eyes operated on for macula-on RRD, which made up the first group, and the control group (20 eyes) for comparison. All patients of the study group underwent vitrectomy using silicone oil tamponade. Standard ophthalmological examination was performed on the 3rd day (early postoperative period) and the 14th day (late postoperative period), including OCT and OCT-A that were used to assess morphological and functional changes. RESULTS: A significant decrease in visual acuity was seen on the 3rd day after surgery involving the use of silicone oil tamponade, in comparison with the 14th day (p=0.0237) and the control group (p=0.0001). A decrease in the FD parameter (p=0.045), a decrease in vascular density in the fovea (p=0.020) and parafovea (p=0.024) in SCP were found on the 3rd day in comparison with control. On the 14th day of postoperative observation, a tendency was detected for choroidal perfusion to restore, as well as significant increase in FD (p=0.016), and an increase in vascular density in parafovea (p=0.01) compared with the early postoperative period. No statistically significant changes were seen in the FAZ area and vessel density DCP (p>0.05).

DFT+U in Dudarev's formulation with corrected interactions between the electrons with opposite spins: The form of Hamiltonian, calculation of forces, and bandgap adjustments.

Hubbard corrected density functional theory (DFT) methods, such as the DFT+U approach in Dudarev's approximation, are widely used for the description of energetics and electronic structure of strongly correlated materials, providing higher level of accuracy than local DFT calculations (e.g., local density approximation or generalized gradient approximation). However, the DFT+U method in Dudarev's formulation limits the introduced corrections to interactions between the electrons within the same spin channel, whereas interactions between the electrons with opposite spins are still treated using local DFT functional (e.g., Perdew-Burke-Ernzerhof). In recent years, the need for correction of these interactions between the electrons with opposite spins has been recognized and additional terms have been added to the Hubbard term to reflect it. Although such extended DFT+U functionals have been proposed, the form of respective Hamiltonian operator, defined as a total energy derivative over density with appropriate treatment of double counting corrections due to additional Hubbard terms, has not been explicitly presented. In this work, we provide an expression for such a type of Hamiltonian, which contains the respective double counting correction contributions. This formulation also allows evaluation of atomic forces, using computational settings discussed herein. In addition, we also introduce adjustments for too narrow theoretical bandgaps, using scissor operator technique. This allows for a greater level of corrections of energetics and magnetic properties of studied transition metal compounds, avoiding possible unphysical overlap between occupied and unoccupied electronic bands.

[Influence of treatment adherence on the progression of primary open-angle glaucoma in clinical setting]. / Vliianie priverzhennosti k lecheniiu na progressirovanie pervichnoi otkrytougol'noi glaukomy u patsientov v usloviiakh klinicheskoi praktiki.

According to various studies, treatment adherence of patients with primary open-angle glaucoma ranges from 5% to 80% and significantly influences the effectiveness of the therapy. Some authors report higher levels of adherence in patients receiving preservative-free medications. PURPOSE: To study the influence of treatment adherence in patients receiving preservative-free and preserved medications on the progression of primary open-angle glaucoma (POAG). MATERIAL AND METHODS: This prospective multicenter non-interventional study was conducted in clinical setting and included 504 patients with primary open-angle glaucoma receiving drug therapy; 51 ophthalmologist was involved in the management of patients' diaries. RESULTS: The percentage of patients who did not reach target IOP was three times lower in the group with high adherence, in comparison to patients with medium and low adherence (7% against 22%, respectively). Development of side effects was one of the factors influencing treatment adherence, their rates and expressiveness were much lower in the preservative-free group compared with the group receiving preserved medication (13.9% against 35.4%). The rate of patients who did not reach target IOP was two times lower in the group of preservative-free medication (10% against 21%). CONCLUSION: The study confirms that preservative-free glaucoma medication promotes higher adherence to treatment in clinical setting predominantly due to the reduction of quantity and severity of side effects leading to treatment gaps, which results in increased effectiveness and better stabilization of glaucoma.

[Cephalometry efficacy in orthodontic treatment planning: correlations of cephalometric values and their changes in the course of treatment]. / Éffektivnost' tsefalometrii v planirovanii ortodonticheskoi korrektsii: vzaimosviaz' mezhdu tsefalometricheskimi parametrami i ikh izmeneniiami v rezul'tate ortodonticheskogo lecheniia (chast' II).

The aim of the study was to assess the efficacy of cephalometry in planning of orthodontic patients with teeth crowding (TC) and Angle Class I molar relationship (MR). Cephalometric values of 70 patients with TC and class I MR were analyzed before and after orthodontic treatment. Cephalometric study of correlations proved to be more relevant than comparing with mean values. In patients with TC and class I MR statistically significant were correlations with: facial profile (ÐN-A-B) and jaws relationship in anterio-posterior direction (ÐA-N-B); ÐN-A-B and type of maxillary growth (ÐPn-Mp, ÐB); ÐB and maxillary incisors inclination (Ðis-SpP); ÐPn-Mp and mandibular incisors inclination (Ðii-Mp). These correlations depend on age, anomaly severity and orthodontic strategy. Cephalometry proved to be effective tool for orthodontic treatment planning, prognosis and modelling.

[Efficiency of cephalometry in orthodontic treatment planning: cephalometric parameters and their age-related changes]. / Éffektivnost' tsefalometrii v planirovanii ortodonticheskoi korrektsii: tsefalometricheskie parametry i ikh vozrastnye izmeneniia (chast' 1).

The aim of the study was to evaluate the efficiency of cephalometry in orthodontic treatment planning in patients with teeth crowding and Angle Class I molars relation. Cephalometric parameters were analyzed in 70 patients that completed orthodontic treatment in 'Orthodont' dental clinic (Samara). Cephalometric X-rays were taken at baseline examination and after treatment. In patients with crowding and Class I molars relationship treated with extraction of all four first premolars correlation between N-Se and mandibular and maxillary length was disturbed. These patients showed higher N-Se and reduced jaws length than patients with no extraction or extraction of 2 premolars. The observed increase of G angle with reduced mandibular length assumes compensatory changes of mandible position. These disproportions were aggravated by facial growth. In certain cases cephalometric assessment is inefficient for treatment strategy choice.

[Clinical and epidemiological characteristics of hemorrhagic fever with renal syndrome in the North-West region of Russia].

The data of the literature and our own research of clinical and epidemiological features of hantavirus infection the North-West region of Russia, showing the loss of endemicity of hemorrhagic fever with renal syndrome. It is noted mostly airborne infection in young and middle-aged men, year-round nature of the disease with seasonal peaks. The clinical picture is moderately prevalent the disease with no or minimal systemic manifestation of hemorrhagic syndrome, often marked by thrombocytopenia, moderate dysfunction and kidney damage in half the time without reducing urine output. The introduction of acute kidney damage concept allows significantly improve the diagnostic efficiency and stratification of renal dvsfunction severity in Datients with hantavirus infection.

Direct solubility determination in optically dense solutions of highly soluble chromophores by the optoacoustic technique: Acidity dependence for Phenol Red.

The optoacoustic (OA) technique capable for light-absorption measurements in highly concentrated solutions is applied for direct solubility assessment in highly absorbing saturated solutions without any dilution or sample preparation. Maximum solubility of Phenol Red in aqueous solutions at pH>11 is found to be 1.3±0.1 g/L. The experimental dependence of solubility of Phenol Red on solution acidity was obtained with optoacoustic and conventional spectrophotometric measurements. The data from both methods show complementary results. The model of the solubility of Phenol Red on solution acidity describing the experimental dependence is proposed, which cannot be attained at pHs above 7 without the OA-technique.

[Stability of orthodontic correction: preconditions of relapses caused by occlusal forces]. / Stabil'nost' ortodonticheskogo lecheniya: predikaty retsidiva, vyzyvaemogo okklyuzionnymi silami.

The aim of the study was to determine the prognostic criteria of orthodontic treatment success in a group of patients with crowded teeth position and a neutral occlusion. The study included 150 patients (123 female and 27 male) with the average follow-up of 10.02±2.88 years and average retention phase of 6.15±2.98 years. Teeth positions, dental arches form, occlusal contacts and periodontal status were studied. Dentition changes after orthodontic correction should be considered as a result of adaptive compensatory balance. The resultant force acting on teeth and the direction of it determine displacement of teeth. The leading relapse precontidion induced by the occlusal forces was the interference of the canines, mandible deviation and asymmetry, muscle tone disorders.

[Effectiveness and safety of antiviral therapy of military personnel suffering from chronic hepatitis C].

In order to evaluate effectiveness and safety of antiviral therapy schemes examined and treated 191 patients with chronic bepatitis C were assigned standard interferon and ribavirin, pegslated interferon and ribavirin, the total duration of the course coput 24-48 weeks. Based on clinical and laboratory parameters evaluated the safety of antiviral therapy. Formation of sustainable viral response, depending on the genotype observed, was given at 58,9-70%.of patients. In case of insufficient. antiviral therapy was prescribed a second course that will improve the effectiveness of treatment to 90-95%. Correction of adverse events was held lower dosages of interferon and/or ribavirin.

Direct modeling of the electrochemistry in the three-phase boundary of solid oxide fuel cell anodes by density functional theory: a critical overview.

The first principles modeling of electrochemical reactions has proven useful for the development of efficient, durable and low cost solid oxide full cells (SOFCs). In this account we focus on recent advances in modeling of structural, electronic and catalytic properties of the SOFC anodes based on density functional theory (DFT) first principle calculations. As a starting point, we highlight that the adequate analysis of cell electrochemistry generally requires modeling of chemical reactions at the metal/oxide interface rather than on individual metal or oxide surfaces. The atomic models of Ni/YSZ and Ni/CeO2 interfaces, required for DFT simulations of reactions on SOFC anodes are discussed next, together with the analysis of the electronic structure of these interfaces. Then we proceed to DFT-based findings on charge transfer mechanisms during redox reactions on these two anodes. We provide a comparison of the electronic properties of Ni/YSZ and Ni/CeO2 interfaces and present an interpretation of their different chemical performances. Subsequently we discuss the computed energy pathways of fuel oxidation mechanisms, obtained by various groups to date. We also discuss the results of DFT studies combined with microkinetic modeling as well as the results of kinetic Monte Carlo simulations. In conclusion we summarize the key findings of DFT modeling of metal/oxide interfaces to date and highlight possible directions in the future modeling of SOFC anodes.

[Adaptive dentoalveolar changes by insufficient sizes of the jaws].

The study is based on analysis of 1800 CT scans performed in patients undergoing orthodontic treatment in Samara dental clinic "Orthodont" from 2007 to 2012. Various adaptive dentoalveolar changes by insufficient sizes of the jaws were identified and classified in 4 groups: (1) adaptation of teeth position associated with jaw size insufficiency; (2) adaptation of alveolar bone associated with jaw size insufficiency; (3) adaptation of teeth position associated with muscle balance; (4) adaptation of teeth associated with space deficiency by their development. Hence adaptive changes involve all dentoalveolar structures influencing orthodontic treatment planning. Some of the changes may not be corrected.