PbMg1/3Nb2/3O3dielectric aging in the freezing temperature region.

Aging of the relaxors and PbMg1/3Nb2/3O3in particular was extensively studied in last two decades. Most of the results were related to the low temperature glass-like region. No systematic data around the freezing temperatures were reported. To cover this still missing information we have studied the evolution of the dielectric spectra in the broad frequency region from 10-1 Hz to 106 Hz both below and above the freezing temperatureTf≈240 K. Below freezing temperature the existence of the earlier reported waiting time-frequency scaling at frequencies below ≈50 Hz is confirmed. At higher frequencies this deviation from the scaling is observed that can be tentatively attributed to the complexity of the relaxing entities. AboveTfaging is observed only in the restricted frequency interval below the maximum of the dielectric loss spectrum. The observed effect can be attributed to the hardening and narrowing of the dielectric loss spectra and decreasing of the dielectric strength with time. The explanation is proposed based on the concept of the creation of the degenerate polar nanoregions covering several chemically ordered regions (COR) (multi PNRs-MPNRs). These MPNRs are large compare to the PNRs located at the single CORs and some of them may become frozen resulting in the described spectra changes.

[Mastoid obliteration during last 5 years]. / Mastoidoplastika: tendentsii poslednikh 5 let.

The article presents modern approaches to mastoid obliteration in cases of chronic purulent otitis media with cholesteatoma, published in peer-reviewed russian and foreign journals from 2017 to 2021. The review tells us about effect of mastoid cavity obliteration on reducing the recurrence of cholesteatoma, improving the quality of life of patients according to the results of international questionnaires and the effect of surgery on hearing in the long-term postoperative period. An analysis of the use of autologous and biocompatible materials in middle ear surgery is presented. Their safety and ease of use during surgical intervention were evaluated.

Multiscale local ordering in the prototypical uniaxial relaxor Sr0.6Ba0.4Nb2O6 single crystal at room temperature.

The structure and diffuse scattering in uniaxial relaxor Sr0.6Ba0.4Nb2O6 single crystal have been studied by x-ray diffraction at room temperature. Two different kinds of local ordering with different correlation lengths and different shapes of correlation functions have been revealed. The values of correlation lengths have been determined from analysis of experimental data. These types of orderings are connected with the intrinsic structure of crystal and can promote the appearance of relaxor properties.

Critical scattering and incommensurate phase transition in antiferroelectric PbZrO3 under pressure.

Antiferroelectric lead zirconate is the key ingredient in modern ferroelectric and piezoelectric functional solid solutions. By itself it offers opportunities in new-type non-volatile memory and energy storage applications. A highly useful and scientifically puzzling feature of this material is the competition between the ferro- and antiferroelectric phases due to their energetic proximity, which leads to a challenge in understanding of the critical phenomena driving the formation of the antiferroelectric structure. We show that application of hydrostatic pressure drastically changes the character of critical lattice dynamics and enables the soft-mode-driven incommensurate phase transition sequence in lead zirconate. In addition to the long known cubic and antiferroelectric phases we identify the new non-modulated phase serving as a bridge between the cubic and the incommensurate phases. The pressure effect on ferroelectric and incommensurate critical dynamics shows that lead zirconate is not a single-instability-driven system.

EPIDEMIOLOGIC AND DEMOGRAPHIC FEATURES OF INTRACRANIAL OTO- AND RHINOSINUSOGENIC PYOINFLAMMATORY COMPLICATIONS IN RUSSIAN FEDERATION.

An analysis of demographic and epidemiologic situation was made in cases of otogenic and rhinosinusogenic intracranial complications on the area of 32 regions of Russian Federation at the period from 2009 to 2014. The state of ENT-service of examined subject is characterized by reduction of provision of during ENT-beds and lower level of hospitalization of population over indicated period. There was revealed a reliable correlated dependence of the main medical statistical indices from the intracranial complications with climatic and demographic factors, the rate of morbidity and activities of ENT-service in the area of this region.

COOPERATIVE MANAGEMENT OF NEUROSURGEON AND OTOLARYNGOLOGIST IN TREATMENT OF CHILDREN WITH OTORHINOGENIC SUPPURATIVE-INFAMMATORY BRAIN DISEASES.

This work analyzed 47 cases of oto- and rhinosinusogenic suppurative meningoencephalitis, abscesses and empyemas of the brain in children at the age from 3 months to 17 years old. The article presents the treatment strategy, results and the volume of diagnostic measures. On the basis of this research, the authors came to conclusion, that care of the children with otogenic and rhinosinusogenic suppurative diseases of the brain required an interdisciplinary approach and effective cooperation of a neurosurgeon, otolaryngologist, pediatrician, resuscitation specialist, infectionist and a clinical pharmacologist.

[The specific clinical features of otogenic intracranial complications: the current views].

The objective of the present study was to elucidate the specific clinical features of otogenic intracranial complications (ICC) encountered in the current otorhinolaryngological practice. The work is based on the results of the retrospective analysis of 106 adult patients presenting with otogenic intracranial complications admitted for the treatment to multidisciplinary clinics of Sankt-Peterburg and Krasnoyarsk. Forty six (42.5%) patients presented with acute otitis media. 90% of them had suppurative destructive mastoiditis. In sixty (56.6%) patients, chronic suppurative otitis media (epitympanophonia) was associated with the extensive destructive process spreading toward dura mater of the medial and posterior cranial fossae and onto the sigmoid sinus. The prevalence of intracranial complications among the adult patients suffering from suppurative otitis media and treated in the otorhinolaryngological clinics amounted to 3.17%. The overall structure of otogenic intracranial complications was as follows: meningitis 42.5%, brain and cerebellum abscess 24.5%, suppurative meningoencephalitis 19.8%, sinus thrombosis 5.7%, epidural and subdural empyemas 4.7%, the combined suppurative brain lesions 2.8%. Systemic inflammatory response syndrome (sepsis) was diagnosed in 33 (31%) patients with otogenic ICC. The high intrahospital mortality rate among the patients with this condition (20.8%) is emphasized. The main causes of the fatal outcome in the patients with otogenic intracranial complications are supposed to be brain oedema with the concomitant development of dyslocation syndrome and sepsis.

Lattice dynamics in the paraelectric phase of PbHfO3 studied by inelastic x-ray scattering.

We report the results of an inelastic x-ray scattering study of the lattice dynamics in the paraelectric phase of the antiferroelectric lead hafnate PbHfO3. The study reveals an avoided crossing between the transverse acoustic and transverse optic phonon modes propagating along the [1 1 0] direction with [1 -1 0] polarization. The static susceptibility with respect to the generally incommensurate modulations is shown to increase on cooling for the entire Γ-M direction. We consider different approaches to the data analysis that correspond to different models for the temperature evolution of the dynamic susceptibility function. A number of similarities and differences between the lattice dynamics of PbHfO3 and PbZrO3 are described.

Neutron diffraction study of the (BiFeO3)1-x(PbTiO3)x solid solution: nanostructured multiferroic system.

Neutron diffraction studies performed on the solid solution of (BiFeO(3))(1-x)(PbTiO(3))(x) reveal a mixture of two nanoscale phases with different crystal structures: a rhombohedral BiFeO(3)-based phase and a tetragonal PbTiO3-based phase. The ratio of Fe(3)+ and Ti(4)+ ions in the two phases is practically constant; only the proportion of the phases changes. The magnetic moments in the BiFeO(3)-based phase, in contrast to BiFeO(3), deviate from the basal plane. The temperature evolutions of the spin components along the hexagonal axis and within the perpendicular plane are different, leading to a spin re-orientation transition. The antiferromagnetic order in the PbTiO(3)-based phase corresponds to a simple structure with the propagation vector (1/2, 1/2, 1/2). The temperature dependence of the antiferromagnetic moment in the tetragonal phase at x = 0.5 indicates a canted antiferromagnetic order and a net ferromagnetic moment. A strong magnetic coupling between the two constituting phases due to the nanoscale character of the phases and well-developed interface between nanoparticles has been observed. The system of (BiFeO(3))(1-x)(PbTiO(3))(x) demonstrates an interesting scenario, where the proximity effects in the unstable system play a crucial role in the appearance of the unusual magnetic properties.

[FEATURES OF OTOGENIC INTRACRANIAL COMPLICATIONS AT THE PRESENT STAGE].

A retrospective analysis of treatment was made in 127 adult patients with acute and chronic otitis media complicated by suppurative-inflammatory pathology of the brain. Purulent meningitis was revealed in 52 (40.9%) of hospitalized patients. Meningoencephalitis was often diagnosed in the cases of acute otitis media (15.4%) and in cases of chronic otitis (22.7%). The otogenic brain abscess was detected in 13.5% of otitis media cases and it was noted to be twice frequent (33.3%) in cases of purulent otitis media. The patients 124 (97.6%) have been operated. An extended mastoidotomy and antromastoidotomy were performed in the acute purulent otitis media. An extended radical operation on the ear was applied in case of chronic otitis media. Performance of craniotomy and complete removal of the abscess using modern systems of neuronavigation showed a higher clinical efficacy as compared with transtemporal approach during sanitizing intervention on the ear including the opening and abscess drainage in surgery of otogenic abscesses of the brain.

[The modern epidemiological characteristics of oto- and rhinosinusogenic intracranial complications].

The objective of the present study was to survey epidemiology of oto- and rhinosinusogenic intracranial complications that are currently diagnosed at the territory of the Russian Federation. The work was based on the analysis of the official statistical reports together with the data obtained from the chief specialists responsible for the otorhinolaryngological services in 32 subjects of the Russian Federation during the period from 2009 to 2014. It was shown that the state of the otorhinolaryngological service in the period covered by the study was characterized by the reduction in the number of beds available for the patients presenting with ENT pathology by 14.0% and the lowering of the hospitalization rate for the general population by 6.3%. The frequency of oto- and rhinosinusogenic intracranial complications among the patients hospitalized to occupy the beds intended for the care of the patients suffering from ENT diseases was estimated at 0.03% and intrahospital lethality at 21.2%. The prevalence of pyogenic intracranial complications associated with the inflammatyory pathology affecting ENT was 0.61 per 100.000 population per year, with the mortality rate amounting to 0.17 fatal outcomes per 100.000 population per year. The study revealed significant correlation of the principal medico-statistical characteristics of high-frequency oscillatory ventilation (HFOV)---?? between themselves and with the parameters of ENT morbidity and activities of the otorhinolaryngological services at the territory of a given administrative territory. It is concluded that the improvement of the quality of healthcare for the population presenting with intracranial complications and inflammatory ENT diseases is possible only on the baseis of the combined and interdisciplinary approach to the solution of the problem.

[Cleft palate surgery with ENT-pathology correction].

The article presents the cases of cleft palate surgical treatment with simultaneous intervention in ENT organs (bypass of the tympanic cavity, segmental or total adenotomy, etc.) with the restoration of vomer anatomy and hard palate reconstruction by means of super-elastic low-profile nickel titanium implant. The article describes the advantages of the method in comparison with the conventional ones.

[Characteristics of cell-mediated and humoral components of the immune response in the children presenting with chronic adenoiditis].

The objective of the present study was to determine the magnitude of characteristics of immunity and estimate the immunological status of the children presenting with chronic adenoiditis (CA) at the stage of remission. The valid sample (n=158) was used to analyse the blood cellular spectrum and humoral characteristics in the children at the age from 2.5 to 10 years residing in the city of Krasnoyarsk. It was shown that the development of CA was associated with the activation of non-specific protective factors and consistent with the general physiological patterns. The total T-lymphocyte population significantly increased which excluded the T-cellular immunodepressive state. The reduction in the absolute and relative number of B-lymphocytes suggested insufficiency of the B cell-dependent component of the immune system in the children that was especially well-pronounced in the younger age group.

The origin of antiferroelectricity in PbZrO3.

Antiferroelectrics are essential ingredients for the widely applied piezoelectric and ferroelectric materials: the most common ferroelectric, lead zirconate titanate is an alloy of the ferroelectric lead titanate and the antiferroelectric lead zirconate. Antiferroelectrics themselves are useful in large digital displacement transducers and energy-storage capacitors. Despite their technological importance, the reason why materials become antiferroelectric has remained allusive since their first discovery. Here we report the results of a study on the lattice dynamics of the antiferroelectric lead zirconate using inelastic and diffuse X-ray scattering techniques and the Brillouin light scattering. The analysis of the results reveals that the antiferroelectric state is a 'missed' incommensurate phase, and that the paraelectric to antiferroelectric phase transition is driven by the softening of a single lattice mode via flexoelectric coupling. These findings resolve the mystery of the origin of antiferroelectricity in lead zirconate and suggest an approach to the treatment of complex phase transitions in ferroics.

Structural heterogeneity and diffuse scattering in morphotropic lead zirconate-titanate single crystals.

Complementary diffuse and inelastic synchrotron x-ray scattering measurements of lead zirconate-titanate single crystals with composition near the morphotropic phase boundary (x=0.475) are reported. In the temperature range 293 K

[Organization of remote long-term support of the patients with cochlear implants in distant regions].

The concept of remote long-term support of the patients with cochlear implants is suggested to cope with the problem of the increasingly growing number of patients with cochlear pathology. The authors deem it necessary to provide intraoperative support and postoperative follow-up technologies for the patients living far from the cochlear implantation centres. A scheme for the remote selection of patients and their intraoperative monitoring is proposed with the use of implant telemetry, electrical stapedial reflex (eSRT) testing, auditory response telemetry (ART), and surgical on-line counseling. Remote follow-up and rehabilitation should include cochlear implant tuning, speech therapy, and on-line workshops for the patients and/or specialists. The choice and the use of software and hardware for this purpose are discussed. The concept of remote long-term support turned out to be an efficacious, reliable, time-saving, and cost-effective tool for providing high-tech medical aid to patients with ENT diseases in the Krasnoyarsk kray (territory).

[The role of environmental factors in the development of pathology of the lymphadenoid pharyngeal ring in children].

The authors present the analysis of the prevalence and structure of pathology of the lymphadenoid pharyngeal ring in children living in the districts of the city of Krasnoyarsk differing in terms of atmospheric pollution. It is shown that that pharyngeal adenoid hypertrophy occurs significantly more frequently in the children from the districts exposed to an extremely high level of atmospheric pollution than in those residing under more favourable environmental conditions.

[Dynamics of immunological characteristics and investigation of apoptosis of palatal tonsillar lymphocytes in patients presenting with chronic tonsillitis and treated by conservative therapy].

The enhanced amount of viable lymphocytes and the decreased number of apoptotic cells as well as the reduced levels of IgA and IgM and the elevated concentration of sIgA in lacunar secretion are considered to be the reliable criteria for the efficacy of the conservative treatment of chronic tonsillitis. Combined therapy of this condition including irrigation of the palatal tonsillar lacunae with a miramistin solution, their contact ultrasonic treatment, and application of imudon makes it possible to maintain the optimal ratio of viable to apoptotic lymphocytes during a period of up to 6-7 months.

[Specific microendoscopic characteristics of intranasal mucosa in patients presenting with chronic rhinosinusitis and treated with sinuforte].

The objective of the present work was to assess the efficacy of the treatment of chronic rhinosinusitis (CR) in the patients treated with sinuforte using the contact microendoscpic technique. This randomized open clinical and instrumental study included 30 patients presenting with chronic rhinosinusitis. All of them were treated with sinuforte as monotherapy at a dose of 1.3 mg per procedure given once daily during 7 consecutive days. The efficacy of the treatment was evaluated by means of endoscopic and microendoscopic examination supplemented by functional tests on days 1, 2, 4, 6, and 8 after the beginning of therapy. In addition, a questionnaire study was carried out. It was demonstrated that the use of sinuforte for the treatment of the patients with chronic rhinjsinusitis is safe and efficacious as confirmed by the morphological picture revealed by contact microendoscopy.

The negative phonon confinement effect in nanoscopic sodium nitrite.

A nanocomposite of porous glass and a NaNO(2) ferroelectric (channels of approximately 7 nm diameter) was studied using infrared reflectivity, THz transmission and Raman spectroscopy as a function of temperature in the range of 300-500 K, including the ferroelectric transition. From the infrared and THz response the effective dielectric function was calculated and compared with the dielectric functions calculated from the Bruggeman and Lichtenecker models of the effective medium, using the known data on the polar phonon modes of the NaNO(2) single crystals. The results show good qualitative agreement, indicating that the stiffening of the effective modes is due to local depolarization fields on the glass-ferroelectric interfaces. The nonpolar Raman modes show no substantial modification compared to those of the bulk NaNO(2). Some signatures of the ferroelectric transition were even seen. The results indicate that the intrinsic size effect (phonon confinement) is negligible in this nanocomposite.