21 research outputs found
Demographic and spatial structure at the stage of expansion in the populations of some alien land snails in Belgorod city (Central Russian Upland)
Field studies of alien terrestrial gastropods Xeropicta derbentina (Gastropoda, Stylommatophora, Hygromiidae), Brephulopsis cylindrica (Gastropoda, Stylommatophora, Enidae) and Harmozica ravergiensis (Gastropoda, Stylommatophora, Hygromiidae) were carried out in the south of the Central Russian Upland in Belgorod (Russia). An analysis of the dynamics of population density, their demographic structure and spatial organization was performed on the basis of data for three years of observations (2017, 2019, 2020)
Regional manifestations of changes in atmospheric circulation in the Central Black Earth region : by the example of Belgorod region
The aim of this work is the estimation of the reasons of occurrence of the area of dangerous hydrometeorological phenomena and the analysis of the circulation processes, leading to the establishment of extreme weather conditions in the region. Using the calendar of the consistent changes of elementary circulation mechanisms and daily observations of the weather in the south of Central Black Earth region (by the example of Belgorod region).yesBelgorod State National Research Universit
Correlation Between the Resistance to Stress Corrosion Cracking of Steel Tubes of Gas Pipelines with Their Layerwise Texture Inhomogeneity
In the present work, the influence of the tubes texture layering on their resistance to stress-corrosion cracking (SCC) is demonstrated by the example of several main gas pipelines (MGP) constructed of X70 steel tubes of different manufactures and operated under various exploitation conditions. X-ray studies of crystallographic texture and structural characteristics were implemented for external and internal layers of various tubes sections, which were cut out from MGP zones with fixed SCC defects and without them. Correlation between the depth of corrosion cracks and the thickness of the surface layer with sharply differing texture parameters is established. The system data analysis also shows that the presence of the texture component {110} <001> in the tubes surface layers can increase their resistance to the SCC.
Keywords: crystallographic texture, structure, texture layering, electron backscattered diffraction, stress corrosion cracking, main gas pipeline, hot rolling
Cardiac tumours in children
Cardiac tumours are benign or malignant neoplasms arising primarily in the inner lining, muscle layer, or the surrounding pericardium of the heart. They can be primary or metastatic. Primary cardiac tumours are rare in paediatric practice with a prevalence of 0.0017 to 0.28 in autopsy series. In contrast, the incidence of cardiac tumours during foetal life has been reported to be approximately 0.14%. The vast majority of primary cardiac tumours in children are benign, whilst approximately 10% are malignant. Secondary malignant tumours are 10–20 times more prevalent than primary malignant tumours. Rhabdomyoma is the most common cardiac tumour during foetal life and childhood. It accounts for more than 60% of all primary cardiac tumours. The frequency and type of cardiac tumours in adults differ from those in children with 75% being benign and 25% being malignant. Myxomas are the most common primary tumours in adults constituting 40% of benign tumours. Sarcomas make up 75% of malignant cardiac masses. Echocardiography, Computing Tomography (CT) and Magnetic Resonance Imaging (MRI) of the heart are the main non-invasive diagnostic tools. Cardiac catheterisation is seldom necessary. Tumour biopsy with histological assessment remains the gold standard for confirmation of the diagnosis. Surgical resection of primary cardiac tumours should be considered to relieve symptoms and mechanical obstruction to blood flow. The outcome of surgical resection in symptomatic, non-myxomatous benign cardiac tumours is favourable. Patients with primary cardiac malignancies may benefit from palliative surgery but this approach should not be recommended for patients with metastatic cardiac tumours. Surgery, chemotherapy and radiotherapy may prolong survival. The prognosis for malignant primary cardiac tumours is generally extremely poor
Regional manifestations of changes in atmospheric circulation in the Central Black Earth region : by the example of Belgorod region
yesThe aim of this work is the estimation of the reasons of occurrence of the area of dangerous hydrometeorological phenomena and the analysis of the circulation processes, leading to the establishment of extreme weather conditions in the region. Using the calendar of the consistent changes of elementary circulation mechanisms and daily observations of the weather in the south of Central Black Earth region (by the example of Belgorod region).Belgorod State National Research Universit
Trends in summer season climate for Eastern Europe and Southern Russia in the early 21st century
The goal of this research is to evaluate changes in temperature and precipitation in the Central Chernozem Region of southwester