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We consider a generalized nonlocal Ginzburg-Landau equation with periodic boundary conditions. For the corresponding initial-boundary value problem we prove the existence of a solution for all positive values of the evolution variable. We study the existence and properties of invariant manifolds. We extract a class of invariant manifolds the union of which forms a global attractor. We describe the structure of the attractor and find the Euclidean dimension of its components. In the metric of the space of initial conditions, we also study the Lyapunov stability and orbital stability of solutions that belong in the global attractor. Bibliography: 11 titles., 1 Introduction We consider the known partial differential equation [Please download the PDF to view the mathematical expression] (1.1) where [Please download the PDF to view the mathematical expression] is [...]

AbstractPurposeMethodsResultsConclusionTo analyze the efficacy and safety of microsecond pulsing laser therapy (MLT) in the management of central serous chorioretinopathy (CSCR) complicated by choroidal neovascularization (CNV).Patients with CSCR complicated by CNV defined as the presence of characteristic OCT angiography features were randomly assigned to either study or control group. All patients of the study group underwent MLT targeting CNV area using navigated laser system followed by at least 6-month follow-up. Sham treatment was performed in the control group. No other treatment or anti-VEGF therapy was used during the follow-up. Main outcome measure was complete resolution of subretinal fluid at the end of follow-up.Twenty-three eyes (13 males and 10 females, mean age 58.2 ± 8.0 years) with a mean CNV area 0.62 ± 0.77 mm2 were included in the study group. Fourteen (60.9%) patients achieved complete resolution of SRF, five (21.7%) patients demonstrated some reduction of SRF, and four (17.4%) patients demonstrated no improvement after MLT in the study group. Twelve eyes (8 males and 4 females, mean age 59.8 ± 4.6 years) were included in the control group where none of them demonstrated resolution of SRF at the end of the follow-up (p = 0.0018 compared to the study group). No adverse effects, such as changes of CNV size, deterioration of exudation, or decline in visual acuity were observed in the study group.Microsecond pulsing laser is an effective and safe option for the treatment of CSCR complicated by relatively small CNV and achieves complete resolution of SRF in 61% of cases. [ABSTRACT FROM AUTHOR]

This research is aimed at analyzing existing plugging compositions and developing a new plugging composition based on phenol-formaldehyde resin. This paper presents the results of studies of a hardening composition based on phenol-formaldehyde resin for repair and insulation work in wells. The plugging composition consists of two parts: Component "A" (resin and additives) and Component "B" (hardener). A resol-type water-soluble phenol-formaldehyde resin was selected for testing. The resin was additionally modified with special additives to improve performance properties. A mixture of acids was chosen as a hardener. Concentrations of resin and hardener were selected to ensure optimal loss of fluidity of the composition for different temperatures. The main physicochemical properties of the plugging composition were determined. The elastic-strength characteristics of the developed composition after curing at various temperatures (Poisson's ratio, Young's modulus, and compressive strength) were assessed. It has been experimentally proven that samples based on phenol-formaldehyde resin do not collapse completely under load but undergo longitudinal and transverse deformations. As the amount of hardener in the system increases, the compressive strength decreases. The presence of the elastic-strength properties of cementing compositions based on synthetic resins distinguishes them favorably from hardening compositions based on cement and microcement. [ABSTRACT FROM AUTHOR]

We consider a system of autonomous nonlinear ordinary differential equations for which the existence conditions for an invariant manifold are satisfied in the case where this manifold is central. It is well known that the theorem on the existence of a central invariant manifold cannot be supplemented with the statement of its uniqueness. We obtain sufficient conditions that guarantee the uniqueness of the central invariant manifold. [ABSTRACT FROM AUTHOR]

The aim of the study was to evaluate the local status of the sclera in lattice retinal degeneration. Patients with lattice degeneration, snail-track degeneration, or horseshoe retinal breaks were included. One lesion of a single eye in each patient was captured with cross-sectional optical coherence tomography (OCT) along and across the greatest lesion dimension. The maximum height of scleral indentation was measured and compared between different lesion types and between lattice lesions with and without retinal breakage or local detachment. The correlation between the maximum height of the scleral indentation of lattice lesions and the age of the patients was calculated. Seventy-five eyes of 75 patients (44.4 ± 14.7 years; 35 males and 30 females) were included. OCT showed variable local scleral indentation in 52 out of 55 (94.5%) lattice lesions, in five out of nine (55.5%) snail-tack lesions, and in three out of eleven (27.3%) horseshoe breaks. The maximum scleral indentation within lattice lesions, snail-tack lesions, and horseshoe breaks was 227.2 ± 111.3, 22.0 ± 49.2, and 88.5 ± 48.4 µm, respectively (p < 0.001 for snail-tack lesions and horseshoe breaks compared to lattice lesions). Lattice lesions with retinal breaks and/or local retinal detachment had statistically significantly lower scleral indentation than those without (p = 0.01). The height of the scleral indentation of lattice lesions was positively correlated with patient age (r = 0.51, p = 0.03). In conclusion, scleral indentation is one of the hallmarks of lattice retinal degeneration and may be associated with a reduced risk of rhegmatogenous retinal detachment. [ABSTRACT FROM AUTHOR]