Dimension-independent Harnack inequalities for subordinated semigroups

Dimension-independent Harnack inequalities are derived for a class of subordinate semigroups. In particular, for a diffusion satisfying the Bakry-Emery curvature condition, the subordinate semigroup with power $\alpha$ satisfies a dimension-free Harnack inequality provided $\alpha \in(1/2, 1)$, and it satisfies the log-Harnack inequality for all $\alpha \in (0,1).$ Some infinite-dimensional examples are also presented

Оценка отдаленных клинико-функциональных изменений у пациентов, перенесших тяжелое COVID-19-ассоциированное поражение легких

The problem of long COVID-19 (COronaVIrus Disease 2019) has been highly relevant for the healthcare system in the last three years. The persistence of respiratory symptoms, radiological and functional changes in COVID-19 patients brings new challenges to the entire medical community. The aim of the study is to explore long-term clinical and functional changes in patients with severe COVID-19-associated lung injury, including assessment of functional and radiological abnormalities of the respiratory system, as well as persistent clinical symptoms a year after the acute phase of the disease. Methods. The study included 45 patients who were examined 3, 6 and 12 months after COVID-19 with severe lung damage (more than 50% according to chest CT in the acute phase of the disease). Patients underwent multispiral computed tomography of the chest organs, a comprehensive study of respiratory function (spirography, body plethysmography and diffusion test); the clinical symptoms were assessed. Results. Chest CT scans showed gradual regression of pathological changes during the follow-up. However, radiographic changes of varying severity persisted after 12 months of follow-up in 51% of patients. A year later, restrictive disorders persisted in 20% of patients and the diffusion capacity of the lungs was reduced in 69% of patients. At the same time, a statistically significant difference in the DLСО level was observed between 3, 6 and 12 months. The severity of dyspnea decreased 1 year after hospitalization in 48% of patients. Conclusion. The obtained results demonstrate a gradual regression of both radiological and functional pathological changes during the 1st year. However, CT changes and deviations of the respiratory function persist in some patients, mainly in the form of a decrease in DLСО, which necessitates further monitoring of this group of patients.Проблема длительного течения COVID-19 (COronaVIrus Disease 2019) сохраняет свою актуальность для системы здравоохранения, а перед медицинским сообществом поставлены новые задачи, связанные с персистированием респираторных симптомов, рентгенологических и функциональных изменений у лиц, перенесших новую коронавирусную инфекцию (НКИ). Целью исследования явилось изучение отдаленных клинико-функциональных изменений у пациентов, перенесших тяжелое COVID-19-ассоциированное поражение легких, с оценкой функциональных и рентгенологических отклонений системы дыхания, а также сохраняющейся клинической симптоматики через 1 год после острой фазы заболевания. Материалы и методы. В исследование включены пациенты (n = 45), обследованные через 3, 6 и 12 мес. после перенесенной НКИ с тяжелым поражением легких (> 50 % по данным компьютерной томографии (КТ) органов грудной клетки (ОГК) в острую фазу заболевания). Выполнялись мультиспиральная компьютерная томография ОГК, комплексное исследование функции внешнего дыхания (ФВД) (спирография, бодиплетизмография и диффузионный тест), оценивалась клиническая симптоматика. Результаты. За время наблюдения по данным КТ ОГК отмечался постепенный регресс патологических изменений, однако через 12 мес. наблюдения у 51 % пациентов рентгенологические изменения различной степени тяжести сохранялись. Через 1 год рестриктивные нарушения сохранялись у 20 % пациентов, а диффузионная способность легких по монооксиду углерода (DLСО) оказалась сниженной у 69 %. При этом статистически значимое различие уровня DLСО наблюдалось между 3-м, 6-м и 12-м месяцами наблюдения. Через 1 год после госпитализации у 48 % пациентов уменьшилась выраженность одышки. Заключение. В течение 1-го года наблюдения продемонстрирован постепенный регресс рентгенологических и функциональных изменений, однако у части пациентов сохраняются КТ-изменения и нарушения ФВД, преимущественно в виде снижения DLСО, при которых требуется дальнейшее наблюдение

Dispersion оf Multi-Walled Carbon Nanotubes in Building Science оf Materials

The paper presents that modification of binding matrices with the help of dispersions of multi-walled carbon nanotubes (MWCNT) makes it possible to increase  physical and mechanical properties of building composites

Spawning of bluefin tuna in the black sea: historical evidence, environmental constraints and population plasticity

<div><p>The lucrative and highly migratory Atlantic bluefin tuna, <em>Thunnus thynnus</em> (Linnaeus 1758<em>;</em> Scombridae), used to be distributed widely throughout the north Atlantic Ocean, Mediterranean Sea and Black Sea. Its migrations have supported sustainable fisheries and impacted local cultures since antiquity, but its biogeographic range has contracted since the 1950s. Most recently, the species disappeared from the Black Sea in the late 1980s and has not yet recovered. Reasons for the Black Sea disappearance, and the species-wide range contraction, are unclear. However bluefin tuna formerly foraged and possibly spawned in the Black Sea. Loss of a locally-reproducing population would represent a decline in population richness, and an increase in species vulnerability to perturbations such as exploitation and environmental change. Here we identify the main genetic and phenotypic adaptations that the population must have (had) in order to reproduce successfully in the specific hydrographic (estuarine) conditions of the Black Sea. By comparing hydrographic conditions in spawning areas of the three species of bluefin tunas, and applying a mechanistic model of egg buoyancy and sinking rate, we show that reproduction in the Black Sea must have required specific adaptations of egg buoyancy, fertilisation and development for reproductive success. Such adaptations by local populations of marine fish species spawning in estuarine areas are common as is evident from a meta-analysis of egg buoyancy data from 16 species of fish. We conclude that these adaptations would have been necessary for successful local reproduction by bluefin tuna in the Black Sea, and that a locally-adapted reproducing population may have disappeared. Recovery of bluefin tuna in the Black Sea, either for spawning or foraging, will occur fastest if any remaining locally adapted individuals are allowed to survive, and by conservation and recovery of depleted Mediterranean populations which could through time re-establish local Black Sea spawning and foraging.</p> </div

Possibilities of computed tomography in patients with dentofacial anomalies prior to surgery

Objective: to estimate the usefulness of computed tomography (CT) data in surgical planning of patients with dentofacial anomalies.Material and methods. The study involved 100 patients with dentofacial anomalies. All patients underwent standard treatment protocol (orthodontic preparation, orthognathic surgery planning, orthognathic surgery, and retention period). During preoperational planning all patients underwent 320-row computed tomography (Toshiba Aquilion ONE, slice thickness – 0.5 mm), in spiral or volumetric tomography mode. Received data was exported to DICOM format. According to CT data, preoperative CT-protocol for this group of patients was developed. Results. The features of dentofacial anomalies were assessed (by Angle's classification, angle β measurement (Baik S.Y., Ververidou M., 2004), assessment of symmetry of upper and lower jaws was performed. Investigation of this patient group included assessment of teeth condition, with special attention to dystopic and impacted teeth due to necessity of their preoperational removal. Mandibular nerves channels were assessed, including localization of mandibular and mental foramens. Temporomandibular joints, paranasal sinuses and nasal cavities were assessed, as it affected the tactics of these patients.Conclusion. Computed tomography is necessary for comprehensive assessment of pathology and surgical planning in patients with anomalies of dental system at preoperative diagnostics and planning steps

ANALYSIS OF A CHANGE IN THE POSITION OF THE HYOID BONE WHEN DISPLACING THE LOWER JAW IN PATIENTS WITH DENTOFACIAL MALFORMATIONS

Objective. To estimate the magnitude of a change in the position of the hyoid bone when displacing the lower jaw during surgical treatment in patients with dentofacial abnormalities.Material and methods. Fifty patients with dentofacial abnormalities (25 and 25 patients with distal and mesial occlusion, respectively) were examined and treated. All the patients underwent multislice spiral computed tomography before and 6 months after surgery. The authors developed linear quantities to analyze the position of the hyoid bone with respect to the skull base and cervical spine. The paired Wilcoxon signed-rank test was used.Results. None of the examined groups was noted to have a statistically significant change in the distance between the basihyoid and the vertebral column, suggesting that the datum was moderately changed. No case of worse respiratory function was found.Conclusion. Our investigation has revealed that mandible displacement during orthognathic surgery causes no critical change in the position of the hyoid bone and hence it has no significant impact on upper airway patency in this area