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The Qilian Shan (or Qilian Mountains), located on the northeastern margin of the Tibetan Plateau, is an actively growing orogenic belt resulting from the far-field impact of the India-Eurasia collision. The northward penetration of the Indian Plate is responsible for intense crustal shortening in the Qilian Shan. However, the tectonic deformation pattern in response to the crustal shortening remains unclear. In this study, we present the regional seismicity, fault activity, and GPS crustal movement velocity field to characterize the active tectonic deformation of the Qilian Shan based on historical data over the past two decades. The results suggest that the western Qilian Shan is characterized by distributed north-south crustal shortening, while the eastern Qilian Shan is dominated by blocklike eastward extrusion of crust along major strike-slip faults coupled with clockwise rotation. North-south crustal shortening and east-west lateral extrusion, two deformation modes responding to the India-Eurasia convergence, match the crustal deformation in the Qilian Shan. The tectonic deformation of the western Qilian Shan is largely in agreement with the former, while the eastern Qilian Shan corresponds closely to the latter. Lower crustal flow beneath the central Tibetan Plateau provides the potential driving force to induce the eastward extrusion of crustal material out of the plateau and the growth of some boundary mountain ranges, such as the Qilian Shan.

Carbonaceous (shungite) rocks have high contents of trace elements, which can get to the environment through natural weathering. Shungite rocks are a group of Precambrian carbonaceous rocks of volcanic and sedimentary genesis in Karelia. In this work we present results of studying the mineral and geochemical compositions of shungite rocks at their outcrops on the shoreline of Lake Onega. The interaction of the Onega waters with shungite rocks led to: (1) the removal of most elements, except for K, Mn, Ba, and Mg, whose contents in the rocks increased; (2) the formation of an assemblage of secondary minerals, such as hematite, jarosite, goethite, chalcocite, anglesite, brookite, and Mn hydroxides. Based on the results obtained, we propose a model of the transformation of high-carbon (shungite) rocks by the Onega waters.

The objects of study were bitumens of sedimentary rocks and paraffin oils of the Middle Devonian-lower Frasnian terrigenous complex of the Timan-Pechora basin. We studied the composition of biomarker hydrocarbons and the carbon isotope composition of individual n-alkanes of bitumens from the cores of the wells of the Omra-Lyzha saddle. The results were compared with similar data on the composition of paraffin oils from the south of the Pechora-Kozhva megaswell. The generation potential and thermal maturity of organic matter were studied by the Rock-Eval pyrolysis method. The maturity of organic matter in the rocks of the studied complex in the Omra-Lyzha saddle and the Pechora-Kozhva megaswell corresponds to the oil window. Data on the carbon isotopy of n-alkanes and on the composition of biomarker hydrocarbons do not contradict the possible genetic relationship between paraffin oils and the organic matter of the host sedimentary complex. Both the studied paraffin oils and the rock bitumens contain early eluting rearranged hopanes atypical of oils of other petroliferous complexes and show high contents of n-alkanes relative to iso-alkanes and polycyclic biomarkers. The content of ¹³C tends to decrease with an increase in the number of carbon atoms in the n-alkane molecule in both oils and bitumen rocks.

Based on the solution of the cellular problem of the theory of elasticity, an analysis of the main types of deformation of the binder cross-reinforced with fibers of the composite was carried out. It is shown that all previously predicted possible types of local deformation of the binder fiber composite are revealed in numerical solutions of the cell problem of the averaging theory. The local stress-strain state of the binder significantly depends on the cross-sectional shape of the fibers. In the case of fibers with a square cross-section, it is possible to estimate the stress-strain state using explicit formulas, while for fibers with sections of other shapes, a computer must be used to calculate the stress-strain state.

It has been found that the heat release in the homogenized composite model is described by Joule-Lenz law for the averaged current strength and voltage. It has been shown that the local electric field strength and the local electric current in a real composite are usually significantly different from those in the averaged model despite the fact that the electric field potentials in the averaged model and the real composite are close.

A simplified numerical method for simulating the penetration of projectiles into fabric targets is proposed which takes into account the type of fabric weaving, the friction forces between the fibers and between the projectile and the fabric, and the transverse dimensions of the fabric. The necessary calculated parameters were selected from a comparison of experimental and calculated data. The proposed method was used to estimate the ballistic resistance of a combined protective composition required to reduce the armor impact. The problem of the nfluence of the projectile shape on the ballistic resistance of fabric armor protection

A brief overview of experimental approaches to the study of the tribology of sliding of various bodies on snow or ice is presented, and a model and a digital twin of a tribological device is proposed. The deformation distribution of a tank with snow rotating at a target speed was obtained by modeling, and the work done by the friction force per sliding cycle was determined by testing the movement of a ski sample on a flat snow surface. The proposed device can be used to evaluate the efficiency of sliding on snow at a given temperature, snow structure, humidity, and the roughness of the ski surface sliding on snow

This paper presents an analysis of the effectiveness of using one-dimensional network models for virtual assessment of hemodynamic indices whose values are widely used in clinical practice to choose a treatment strategy for coronary heart disease with stenotic lesions of the coronary arteries. It is shown that existing approaches make it is possible to assess hemodynamic indices based on clinical data collected without intervention in the body with an accuracy comparable to the accuracy of the input data and direct measurements. It is also important to take into account the state of the myocardium microvasculature and its influence on the interpretation of modeling results and direct measurements in the clinic

An approach is proposed for quantitative assessment of the shagginess of the lumen of a pathologically altered aorta, taking into account the three-dimensional morphology of its internal surface. An algorithm for assessing local shagginess has been developed and implemented, and an integral criterion for shaggyness in the anatomical region has been proposed. The algorithm was tested on data from two patients with a shaggy and a smooth lumen. The results obtained are in good agreement with the results of visual assessment by expert surgeons and are confirmed by clinical outcomes during surgery

Salmonella typhimurium and Listeria monocytogenes bacteria, which are two important bacteria used for bacterial therapy purposes in order to limit tumor growth, are studied. Mechanical specifications of the bacteria obtained applying nanoindentation with the use of atomic force microscopy (AFM) are reported. The results show that Salmonella typhimurium bacteria have a greater elastic modulus, but smaller adhesion than Listeria monocytogenes bacteria. The elastic modulus of the AFM extension stroke is larger than that of the retraction stroke. The resonant frequencies and amplitudes of the frequency response function of the AFM beam's vertical movements with two bacteria as samples are investigated using the finite element method. The results show that an increase in the elastic modulus of the sample raises the resonant frequency; therefore, the resonant frequency of Salmonella typhimurium bacteria is greater than that of Listeria monocytogenes bacteria. The results obtained by the finite element method and experimental techniques are found to be in good agreement.