Calculation of the surface effect in the ferromagnetic conductor with the harmonic electromagnetic field

The authors of the paper have obtained formulas for analytical calculation of the constants with the harmonic electromagnetic field, which characterize the surface layer (a skin layer) of the ferromagnetic conductors in case of heating and nonlinear magnetic properties, which can be used for practical calculation of the electromagnetic screens, rotors of the electrical machines and inductive heating installations. A nonlinear dependence of the magnetic induction on the magnetic tension of the ferromagnetic conductor is replaced by one or two linear sections. It is considered that the skin layer of the conductor has constant quantities of the specific conductivity and averaged temperature. Linear electrodynamics equations are solved for the conductive half-space. Parameters of the ferromagnetic conductor's surface layer are calculated: magnetic permeability, the thickness of the skin layer and its averaged temperature, exposure time of the electromagnetic field on the conductor with the established maximum temperature on the conductor's surface, pressure of the field on the conductor and its resistance, inductivity of the internal magnetic field in the conductor, the thermal energy capacity. The methods credibility is confirmed with the concurrence of the resistance and inductiviry of the ferromagnetic conductor with analogous quantities from other methods

ESTIMATION OF AN EPIDEMIOLOGICAL SITUATION ON DIPHYLLOBOTHRIASIS IN PERM KRAI

The article reviews the problems of prevalence of diphyllobothriasis in Perm. Krai. The territories of risk on the diphyllobothriasis morbidity are revealed

Influence of platelets rich plasma (PRP) on the regeneration of skin conditions allergic dermatitis

Introduction: Modern approach to the problem of skin diseases characterized by the influence on the regeneration of tissues at the cellular level, leading to restoration of structure and function of the body as a whole. Aim: to examine the effects of PRP on regenerative properties of skin conditions allergic dermatitis. Materials and methods: Experiments were performed on female mice ICR, aged 3-4 months. PRP received by treating peripheral blood Machinery Smart Prep (Harvester Corp.). Animals were divided into two groups. The first group in plot area for 10 days rubbed potassium dichromate, then locally, intradermal injected into the alfected area PRP dose of 0.1 ml twice at intervals of 7 days. The second group of animals rubbed dichromate of potassium, during the same periodand then watched the self-healing skin. Animal deduced from the experiment on the 17th, 31st and 45th day. Conducted pathologic study involved skin using different methods of coloring material. Results: Macroscopically, visible damages to skin were not observed at the animals of the first group. The skin was covered with hair. In the morphological study of the skin revealed the preservation of its layer structure, satisfactory vascularization of the zone lesions, expressed basal layer, the structure of hair is not changed. Macroscopically, the skin of the animals from the second group was thin, with varying degrees of proliferation of connective tissue. Microscopically we detected acanthosis, small spongiosis, without bubbles, leukocyte infiltration of various degrees of severity, extension of epidermal outgrowths, areas of parakeratosis and phenomenon of acantholysis. Blood vessels had a small caliber. Conclusions: PRP promotes high quality and rapid reparative regeneration of skin, which helps preserve the morphological properties of tissue. The positive effect correction caused by several factors (cytokines and other biologically active substances), which enhance chemotaxis and proliferation of cellular elements in the lesion focus, and participate in the processes of adaptation

ANALYSIS OF NOISE-INDUCED EXTINCTION IN THE GENERALIZED RICKER MODEL OF POPULATION DYNAMICS

The article studies stochastic sensitivity and noise-induced extinction in nonlinear two-dimensional Ricker model with Allee effect and delay.Исследование выполнено при поддержке РФФИ (грант 16-08-00388)

Ion-Pair Chromatography for the Determination of Capreomycin Sulfate Components and Related Substances

Chromatographic methods for the analysis of antibiotic degradation products are widely used to evaluate the quality of medicines. Natural multicomponent antibiotics, such as capreomycin, are the most challenging compounds in terms of developing analytical procedures for related substances. Capreomycin sulfate monographs of the leading pharmacopoeias do not contain specifications for related substances. The key requirement concerns the sum of the main components of capreomycin calculated by normalising the peak areas in the test solution chromatogram. Therefore, it is important to develop an analytical procedure for determining not only the main components but also related substances of capreomycin.The aim of the study was to develop an analytical procedure for determining both the main components (IA, IB, IIA, and IIB) and related substances of capreomycin by ion-pair ultra-high-performance liquid chromatography (UHPLC).Materials and methods. This study examined capreomycin sulfate powder, an active pharmaceutical ingredient (API). Capreomycin sulfate solutions were analysed after artificial degradation (alkaline or acid hydrolysis) to demonstrate the resolution, selectivity, and efficiency of the experimental chromatographic system. The authors used an Agilent 1100 liquid chromatography instrument (Agilent Technologies) and chromatographic columns: Kinetex C18, YMC-Triart С18, ACQUITY UPLC BEH C18, ACQUITY UPLC BEH C8, ACQUITY UPLC BEH Phenyl, and ACQUITY UPLC CSH C18 (experimental procedure) or Acclaim C18, Zorbax SB-C18, and XBridge BEH130 C18 (The International Pharmacopoeia procedure).Results. In contrast to pharmacopoeial procedures, which evaluate only the component composition, the experimental procedure under the selected chromatography conditions can determine both the component composition and related substances of capreomycin. This advantage results from substituting a column packed with 1.7 µm particles for a 5 µm column required for pharmacopoeial procedures. The experimental procedure remains suitable for liquid chromatography instruments with a pressure limit of no more than 400 bar in the gradient elution mode with two mobile phases. According to the efficiency and selectivity evaluation, ACQUITY UPLC BEH C18 columns (150 × 2.1 mm, 1.7 μm) provide optimal peak resolution for capreomycin isoforms and related substances after artificial degradation of capreomycin.Conclusions. This experimental procedure based on ion-pair UHPLC may be used in the production and stability testing of capreomycin medicines to evaluate the API quality by the content of its main components and related substances

GENDER-SPECIFIC INFLUENCE OF Aу MUTATION ON PROGENY METABOLIC PHENOTYPE, FETAL GROWTH AND PLACENTAL GENE EXPRESSION IN MICE

Obesity during pregnancy increases the risk of obesity in offspring. To correct the offspring development in obese mothers, it is necessary to reveal the molecular mechanisms that mediate the influence of the maternal environment on the offspring ontogenesis. Leptin levels increase with obesity. In C57Bl mice, the Ау mutation is associated with elevated blood levels of leptin in pregnant females and exerts a gender-specific effect on the metabolic phenotype of mature offspring. Aim: to study the influence of Ау mutation on sensitivity to diet-induced obesity in male and female offspring, on fetal and placental weight and on the expression of genes in the placentas of the fetuses of different sexes. Body weight and food intake on a standard and an obesogenic diet, fetal and placental weights on pregnancy days 13 and 18, and gene expression of glucose transporters (GLUT1, GLUT3), neutral amino acid transporters (SNAT1, SNAT2, SNAT4), insulin-like growth factor 2 IGF2 and its receptor IGF2R were measured in male and female offspring of и ɑ/ɑ (control) and Ау/ɑ mothers. Ay mutation influenced the body weight only in male offspring, which consumed a standard diet, and did not influence obesity development in both male and female offspring. The weight of fetuses and placentas in Ау/ɑ as compared to ɑ/ɑ  females was reduced on day 13 of pregnancy and was not different on day 18. On day 13 of pregnancy, the mRNA levels of the examined genes did not differ in placentas of male and female fetuses in ɑ/ɑ  females. In Ау/ɑ females, the gene expression of GLUT1, GLUT3, SNAT1 and SNAT4 was reduced in female placentas compared to male placentas. The results suggest that the sex-specific transcription response of placentas to elevated leptin levels in pregnant Ау/ɑ females can mediate the gender-specific impact of Ау mutation on the offspring metabolism in postnatal life