The role of infusoria and bacteria as food for Cyclopoida in Rybinsk Reservoir [Translation from: Trudy Instituta Biologii Vnutrennykh Vodnany 22(25), 37-42, 1971]

Despite the fact that it is a long time sinc e the methods of collection and quantitative estimatio n of protozoa were worked out data on the abundance of these animals in freshwaters are not very numerous. Nevertheless, Infusoria and Rhizopoda at high densities are widespread in the water and sediments of lakes and reservoirs. In order to find ou t the importance of infusoria as a food source for cyclopoids we carried out experimental investigations using C14. For this three species of cyclopoids, widely distributed in open regions of Rybinsk reservoir were selected: Cyclops vicinus, Mesocyclops oithonoides and Kesocyclops leuckarti. The data presented give evidence that the species investigated are able as predators to consume infusorian plankton arid bacteria in the form of flocs or small clumps of detritus

Analysis of the thermal conditions of pulse impact avalanche transit-time diodes

The nonstationary problem of the thermal process for the pulse mode of impact avalanche transit-time diodes is solved. The one-dimensional thermal model of such diodes, which takes into account the heterogeneity of the thermal power distribution and the heat spreading along the heat sink in the operating temperature range, is considered. The numerical calculation results of the average temperature of the active layer and the thermal resistance on the pulse parameters, as well as on the geometric and thermophysical diode parameters, are presented. При цитуванні документа, використовуйте посилання http://essuir.sumdu.edu.ua/handle/123456789/9333Розв’язана нестаціонарна задача теплового процесу для імпульсного режиму ЛПД. Розглянута одновимірна теплова модель цих діодів, в якій враховані неоднорідність розподілу теплової потужності та розтікання тепла вздовж тепловідводу у робочому інтервалі температур. Наведені результати чисельного розрахунку залежності середньої температури активного шару та теплового опору від параметрів імпульсу, а також від геометричних та теплофізичних параметрів діода. При цитировании документа, используйте ссылку http://essuir.sumdu.edu.ua/handle/123456789/9333Решена нестационарная задача теплового процесса для импульсного режима ЛПД. Рассмотрена одномерная тепловая модель этих диодов, в которой учтены неоднородность распределения тепловой мощности и растекания тепла по теплоотводу в рабочем интервале температур. Приведены результаты численного расчета зависимости средней темпе-ратуры активного слоя и теплового сопротивления от параметров им-пульса, а также от геометрических и теплофизических параметров диода. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/933

Migration of Frenkel Excitons in PIC J-aggregates

Using luminescent exciton traps, an efficiency of the exciton migration in J-aggregates of pseudoisocyanine dye in solutions has been investigated. Applying a modified Stern-Volmer equation for an analysis of the J-aggregates luminescence quenching by the trap, the quenching of 50% of PIC J-aggregates luminescence at the ratio PIC/trap = 70:1 has been found. To increase the exciton migration efficiency, the Jaggregate structure was improved by the formation of a "J-aggregate-surfactant” complex. It results in 35% enhancement of the exciton migration efficiency in PIC J-aggregates. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3509

Pyroelectric study of polarization switching in Langmuir-Blodgett films of poly(vinylidene fluoride trifluoroethylene)

The ferroelectric switching in Langmuir-Blodgett films of poly (vinylidene fluoride trifluoroethylene) is studied. The films have a distribution of switching times several decades wide. Nearly a half of the film volume may be switched faster than 1 ms, though complete switching of a whole sample may require 100 s or more. The switching occurs through a domain nucleation and growth mechanism. The decay of polarization at zero bias is logarithmic in time, with a constant rate below 5% per decade at room temperatures. The coercive voltage may be as low as 5 V, which makes the films promising for use in nonvolatile random-access data storage

Critical point in ferroelectric Langmuir-Blodgett polymer films

The ferroelectric critical point has been found in a ferroelectric polymer by exploring the influence of the electric field on the paraelectric-ferroelectric phase transition. Dielectric and pyroelectric measurements on 30-monolayer-thick films of the crystalline copolymer poly(vinylidene fluoride-trifluoroethylene) grown by Langmuir-Blodgett deposition show a single hysteresis loop below the zero-field phase transition temperature Tc0=80±10 °C, double hysteresis loops between Tc0 , and the critical temperature Tcr=145±5 °C, and no hysteresis above Tcr where the critical electric field is Ecr=0.93±0.1X109 V/m

Spectroscopic Study of Cationic Carbocyanine Dye Binding to GdYVO4:Eu Nanoparticles

The interaction of the inorganic nanoparticles (GdYVO4:Eu, d 2 nm) and organic carbocyanine dye 3,3’ -diethyloxa-carbocyanine iodide (DiOC2) has been studied spectrophotometrically. The formation of complexes of dye molecules with spherical nanoparticles GdYVO4:Eu in aqueous solutions of cationic dye DiOC2 was found. It is shown that nanoparticle GdYVO4:Eu can form a complex with 5-10 molecules of the cationic dye DiOC2 which leads to the decrease in the intensity of the absorption and luminescence spectra of the dye in aqueous solution. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3500

Migration of Frenkel Excitons in PIC J-aggregates

Using luminescent exciton traps, an efficiency of the exciton migration in J-aggregates of pseudoisocyanine dye in solutions has been investigated. Applying a modified Stern-Volmer equation for an analysis of the J-aggregates luminescence quenching by the trap, the quenching of 50% of PIC J-aggregates luminescence at the ratio PIC/trap = 70:1 has been found. To increase the exciton migration efficiency, the Jaggregate structure was improved by the formation of a "J-aggregate-surfactant” complex. It results in 35% enhancement of the exciton migration efficiency in PIC J-aggregates. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3509

M-Theory Giant Gravitons with C field

We find giant graviton configurations of an M5-brane probe in the D=11 supergravity background generated by a stack of non-threshold (M2,M5) bound states. The M5-brane probe shares three directions with the background and wraps a two-sphere transverse to the bound states. For a particular value of the worldvolume gauge field of the PST formalism, there exist solutions of the equations of motion for which the M5-brane probe behaves as a wave propagating in the (M2,M5) background. We have checked that the probe breaks the supersymmetry of the background exactly as a massless particle moving along the trajectory of its center of mass.Comment: 11 pages, LaTeX; v2: references adde

Anxiety and depression in patients with multiple sclerosis

Multiple sclerosis is a chronic progressive inflammatory autoimmune disease of the central nervous system. This disease mainly affects young females and leads to disability of the patient, which causes a significant socio-economic burden which this disease causes. Clinically, multiple sclerosis is characterized by a wide variety of neurological and neuropsychological manifestations: movement disorders, sensory disturbances and cognitive dysfunction. One of the most typical psycho-emotional disorders that occur in patients with multiple sclerosis are anxiety and depression. The article is devoted to the study of the features of these disorders in patients with multiple sclerosis. The purpose of the study is to evaluate and characterize psycho-emotional disorders in patients with relapsing-remitting multiple sclerosis. The study included 105 patients with relapsing-remitting multiple sclerosis who underwent inpatient treatment in the Department of Neurology No. 1 Municipal Institution “Dnipropetrovsk Regional Clinic Hospital named after I.I. Mechnykov" Dnipropetrovsk Regional Council". Among the patients included in the study, there were 74 women (70.5%) and 31 men (29.5%). The largest proportion of those surveyed falls on the age group from 25 to 40 years – 80 (76.2%). All participants were assessed according to the generally accepted scale for multiple sclerosis patients assessment – Expanded Disability Status Scale (EDSS). All study participants were divided into two groups – group 1 and group 2 – according to the degree of disability according to EDSS. Considering that the degree of disability according to EDSS≤3.5 is defined as mild, and most patients had just this level, they were assigned into group 1, patients with a score of 3.5<EDSS≤6.5 points were assigned to group 2 with a moderate degree of disability. The number of participants in group 1 was 73 patients (69.5%), group 2 – 32 (30.5%). The psychoemotional sphere was assessed using validated psychodiagnostic tests: Beck Depression Inventory and the State-Trait Anxiety Inventory. The average level of depression, determined by Beck Depression Inventory, was 16.0 (13.0; 18.0) points among all examined, in patients of the 1st group – 14.0 (11.0; 16.0) points, while in patients of the 2nd group it was significantly higher (p<0.001) and amounted to 19.0 (19.0; 24.5) points. Assessment of the level of anxiety according to State-Trait Anxiety Inventory showed that in the majority of patients (84.8%) the level of reactive anxiety was moderate (31-44 points) and made up 36.0 (34.0; 39.0) points. Indicators of personal anxiety in most cases (69.5%) were low (up to 30 points) and averaged 27.0 (24.0; 31.0) points. It should be noted that the level of reactive anxiety exceeded the level of personal anxiety in the study groups and in general among all examined (p<0.001 for all comparisons). Anxiety and depression are very common psychoemotional disorders in patients with relapsing-remitting multiple sclerosis. The relationship between the degree of depression, as well as personal and reactive anxiety and the degree of disability according to the EDSS, has been revealed, but the origin of these disorders is still not clear. Given the significant influence of psycho-emotional disorders on the quality of life of patients and the course of the disease, timely diagnosis and treatment should be the priority areas of management of patients with multiple sclerosis

Energy levels in muonic helium

The energy spectrum of bound states and hyperfine structure of muonic helium is calculated on the basis of stochastic variational method. The basis wave functions of the muonic molecule are taken in the Gaussian form. The matrix elements of the Hamiltonian are calculated analytically. For numerical calculation, a computer code is written in the MATLAB system. As a result, the numerical values of bound state energies and hyperfine structure for muonic helium are obtained.The work is supported by the RSF (Grant 18-12-00128)