High frequency polarization switching of a thin ferroelectric film

We consider both experimentally and analytically the transient oscillatory process that arises when a rapid change in voltage is applied to a $Ba_xSr_{1-x}TiO_3$ ferroelectric thin film deposited on an $Mg0$ substrate. High frequency ($\approx 10^{8} rad/s$) polarization oscillations are observed in the ferroelectric sample. These can be understood using a simple field-polarization model. In particular we obtain analytic expressions for the oscillation frequency and the decay time of the polarization fluctuation in terms of the material parameters. These estimations agree well with the experimental results

Electromagnetically induced switching of ferroelectric thin films

We analyze the interaction of an electromagnetic spike (one cycle) with a thin layer of ferroelectric medium with two equilibrium states. The model is the set of Maxwell equations coupled to the undamped Landau-Khalatnikov equation, where we do not assume slowly varying envelopes. From linear scattering theory, we show that low amplitude pulses can be completely reflected by the medium. Large amplitude pulses can switch the ferroelectric. Using numerical simulations and analysis, we study this switching for long and short pulses, estimate the switching times and provide useful information for experiments

Indicators of Pasture Digression in Steppe Ecosystems of Mongolia

The research shows that widely used key measures of vegetation structure (species diversity, projected cover and above-ground phytomass) are not always suitable as indicators of pasture degradation. Based on an analysis above-ground phytomass composition, new quantitative indices are offered that give a more realistic picture of rangeland condition in Mongolia

Commitment of Parents and Doctors of Irkutsk City to Vaccination against Tick-Borne Encephalitis

Today in Irkutsk region, we face a noticeable increase in the number of cases of ixodid tick sucking to urban residents. Ticks, found in the territory of Irkutsk city, were detected to have all currently known pathogens causing such serious diseases as tick-borne encephalitis, tick-borne borreliosis, monocytic ehrlichiosis, granulocytic anaplasmosis, rickettsiosis and tick-borne recurrent fever. These diseases may develop to severe  forms, and lead to disability or even death.  The aim of the study was to evaluate the opinion of parents and doctors on vaccination against tick-borne viral encephalitis in Irkutsk based on the data of an anonymous questionnaire survey.Material and methods. The descriptive retrospective epidemiological study was conducted between November 2018 and January 2019. It included 1620 parents and 193 doctors of various specialties in Irkutsk. Statistical processing of the material was carried out using Excel tables (Windows 2010) and the Statistica 6.0 program.Results and discussion. In general, the attitude towards vaccination looks positive – 98 % of the parents vaccinate their children. 11.3 % of parents vaccinate their children from tick-borne encephalitis, 23.3 % of doctors vaccinate themselves. Every fourth doctor vaccinates his child against this infection.Conclusion. Insufficient vaccination coverage against tick-borne encephalitis is noted both among the population and among doctors of Irkutsk. It is important to introduce health education for the population and to adopt new ways for improving the qualifications of doctors in immunization issues

Comparative characteristics of clinical, laboratory and instrumental indicators in children with seasonal influenza depending on the virus strain

Introduction. According to the literature, it is known that clinical signs and symptoms of influenza may differ depending on age, the state of the human immune system, the serotype of the virus and its virulence. Intoxication, catarrhal and hyperthermia are main symptoms of influenza, but the disease does not always proceed classically, it may hide under the mask of other infections.   The aim was to conduct a comparative analysis of clinical, laboratory and instrumental parameters in children with influenza A(H1N1) and A(H3N2).   Materials and methods. A single-stage retrospective comparative study was carried out with the participation of 96 children from 1 month of age up to 13 years old with a diagnosis of influenza, who were hospitalized at the Irkutsk Regional Infectious Clinical Hospital from December 2018 to January 2019. Clinical and laboratory features of the course of influenza in children were determined depending on a viral strain.   Results. The structure of morbidity: influenza A(H1N1) – 70 people (73 %), influenza A(H3N2) – 20 children (21 %), influenza A clinically unvaccinated – in 3 people (3 %), mixed viral infection influenza H1N1 + adenovirus infection – 2 cases (2 %), mixed viral infection H1N1 flu + RS-virus – 1 case (1 %). In the clinic of both strains of the virus, symptoms prevailed: runny nose, dry cough, fever, intoxication. Muscle pain and pharyngeal hyperemia were significantly more common in influenza A(H1N1), the duration of symptoms did not differ. Lymphocytosis was more often observed in influenza A(H1N1), monocytosis – in influenza A(H3N2) (р < 0.05). In 64 % of cases, patients with influenza A(H1N1) had a high leukocyte index of intoxication (odds ratio – 2.2).   Conclusion. The symptoms of different influenza A viral strains virus in children are the same, however, muscle pain and hyperemia of the pharynx prevails in children with influenza A(H1N1)

New insights into electron spin dynamics in the presence of correlated noise

The changes of the spin depolarization length in zinc-blende semiconductors when an external component of correlated noise is added to a static driving electric field are analyzed for different values of field strength, noise amplitude and correlation time. Electron dynamics is simulated by a Monte Carlo procedure which keeps into account all the possible scattering phenomena of the hot electrons in the medium and includes the evolution of spin polarization. Spin depolarization is studied by examinating the decay of the initial spin polarization of the conduction electrons through the D'yakonov-Perel process, the only relevant relaxation mechanism in III-V crystals. Our results show that, for electric field amplitude lower than the Gunn field, the dephasing length shortens with the increasing of the noise intensity. Moreover, a nonmonotonic behavior of spin depolarization length with the noise correlation time is found, characterized by a maximum variation for values of noise correlation time comparable with the dephasing time. Instead, in high field conditions, we find that, critically depending on the noise correlation time, external fluctuations can positively affect the relaxation length. The influence of the inclusion of the electron-electron scattering mechanism is also shown and discussed.Comment: Published on "Journal of Physics: Condensed Matter" as "Fast Track Communications", 11 pages, 9 figure

GENERATION OF BLOOD THROMBIN IN PATIENTS WITH CANCER OF PANCREATOBILIARY ZONE COMPLICATED WITH OBSTRUCTIVE JAUNDICE

Obstructive jaundice is one of the most frequent complications of cancer of pancreatobiliary zone that starts the developments of hemorrhagic complications. This group of patients has decrease of coagulation potential that is expressed in changes of process of thrombin generation even before the operative treatment. The article presents the results of the research of indices of process of thrombin generation by Calibrated. Automated. Thrombogram. method in 57 patients with cancer of pancreatobiliary zone complicated with obstructive jaundice before the operative treatment

The association study of polymorphic variants of hypothalamic-pituitary-adrenal system genes (AVPR1B, OXTR) and aggressive behavior manifestation: a focus on social environment

Considering a multifactorial nature of developing aggression, the present study is aimed to estimate both the genetic- and haplotype-based effects of the OXTR and AVPR1B genes and gene-by-environment interactions in developing A

Flu in children: Clinical, laboratory indicators and cytokine profile parameters

Introduction. Respiratory diseases occupy a leading place in the structure of pathology of childhood. The proportion of influenza and acute respiratory viral infections among all infectious diseases is 90 %. The literature describes gender differences in the immune response to respiratory infections in children, but there is a gap in  the  description of the cytokine profile in  children with influenza depending on gender and age.The aim. To analyze clinical and laboratory parameters as well as cytokine profile parameters in children with influenza.Materials and methods. A single-stage descriptive study was conducted with the participation of 50 children from 1 to 11 years of age with a diagnosis of influenza who were on inpatient treatment at the Irkutsk Regional Infectious Diseases Clinical Hospital from December 2018 to January 2019. The clinical and laboratory features of the course of influenza in children, the duration of treatment were determined. The concentration of cytokines interleukin (IL)  1β, IL-4, IL-6, IL-8, tumor necrosis factor alpha (TNF-α), interferon alpha and gamma (INF-α, INF-γ) in blood plasma was determined by enzyme-linked immunosorbent assay (ELISA) using diagnostic test systems manufactured by Vector-Best (Novosibirsk, Russian Federation) on the analyzer Multiscan EX (Thermo Electron, Germany).The control group consisted of practically healthy children without signs of acute respiratory viral infection (n = 50; mean age 5.3 ± 2.6 years).Results. When comparing clinical and laboratory data and cytokine profile parameters in children with influenza, no gender differences were found. There was a statistically significant increase in the level of pro-inflammatory cytokines IL-1β, IL-6, IL-8, TNF-α, INF-α, as well as CRP, anti-inflammatory cytokine IL-4 in influenza in all age categories, in contrast to the control group (p < 0.05).Conclusion. Influenza in children of different sexes proceeds classically without a statistical difference in clinical and laboratory parameters and in the level of cytokines

The capabilities of an extremely low frequency electromagnetic field application in the oncopathology treatment

The findings of investigation of high-level extremely low frequency pulse alternate electromagnetic field inadequate local exposure on the spontaneous malignant tumors of the nonpedigreed dogs' mammary glands are presented. The applied conditions have provided selective exposure with malignant tumors medical pathomorphism of the 1 -2 rates without appreciable structural changes in healthy tissues for certain.Представлены результаты исследования неадекватного локального воздействия высокоинтенсивного инфранизкочастотного импульсного знакопеременного электромагнитного поля на спонтанные злокачественные новообразования молочных желёз беспородных собак. Использованные режимы достоверно обеспечили избирательное воздействие на опухоли с лечебным патоморфозом I - II степени без заметных структурных изменений в здоровых тканях