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The solution of inverse problem concerning non-stationary kinematic loading of elastic half-space is considered in the given article. Kinematic loading applied to the surface of half-space is the result of inverse problem solving. Axisymmetric statement of the second boundary value problem is under consideration. The problem is solved by using expansion in a series in the form of cylindrical functions. The numerical examples of inverse problem solving are represented.

The article describes a unique clinical case of AL amyloidosis mimicking IgG4-related disease. Plasma cell dyscrasias can mimic clinical and laboratory manifestations of rheumatic diseases, which can lead to a delay in diagnosis and inappropriate therapy.

We inquire whether there are some fundamental interpretations of elementary inequalities in terms of curvature of a three-dimensional smooth hypersurface in the four-dimensional real ambient space. The main outcome of our exploration is a perspective of regarding the natural substance of some mathematical inequalities, which represent important physical quantities.

We formulate a compartmental model of the murine lymphatic system with the transfer rate parameters derived from the data on the geometric characteristics of the lymphatic system (LS) graph structure and the Hagen–Poiseuille-based values of the lymph flows through the system components, i.e., vertices and edges. It is supplemented by the physics-based model of lymph node draining-related function which considers a paradigmatic view of its geometry with one- and three-afferent lymphatic vessels and one efferent vessel, and the lymph flow described by the Darcy–Starling equations. We discuss further modelling work needed to gain a predictive understanding of the LS function in response to various perturbations including infections and therapeutic treatments. [ABSTRACT FROM AUTHOR]

Introduction/purpose: In this study, we investigated the possibility of removing the organophosphorus pesticide malathion from water using a new adsorbent based on the biowaste of river shell shards from the Anodonta Sinadonta woodiane family, a material that accumulates in large quantities as waste on the banks of large rivers. Two adsorbents were tested - mechanically comminuted river shells (MRM) and mechanosynthetic hydroxyapatite from comminuted river shells (RMHAp). Methods: The obtained adsorbents were characterized and tested for the removal of the organophosphorus pesticide malathion from water. In order to predict the optimal adsorption conditions using the Response Surface Method (RSM), the authors investigated the influence of variable factors (adsorption conditions), pH values, adsorbent doses, contact times, and temperatures on the adsorbent capacity. Results: The best adsorption of malathion was achieved at mean pH values between 6.0 and 7.0. The adsorption data for malathion at 25, 35, and 45 °C were compared using the Langmuir, Freundlich, DubininRadushkevich (DR), and Temkin isothermal models, as well as pseudofirst order, pseudo-second order and Elovic kinetic models for modeling adsorption kinetics. The maximum Langmuir adsorption capacity for MRM and RMHAp at 25 °C was 46,462 mg g-1 and 78,311 mg g-1 , respectively. Conclusion: The results have showed that malathion adsorption on both adsorbents follows the pseudo-second kinetic model and the Freundlich isothermal model. The thermodynamic parameters indicate the endothermic, feasible, and spontaneous nature of the adsorption process.

The relevance. Temperature measurements in water-filled boreholes and wells are used for solving a wide range of exploration, geophysical, environmental, hydrogeological, and geodynamic problems. Free thermal convection that occurs in boreholes with a geothermal gradient exceeding a critical value causes two types of thermal effects – non-stationary effect and quasi-stationary one. The non-stationary effect is manifested by non-periodic temperature fluctuations relative to a certain average value (temperature noise) and operates in a wide range of frequencies – from seconds to hourly. The quasi-stationary effect is associated with long-term deviations of temperature and gradient in the borehole relative to the undisturbed characteristics in the surrounding rocks. The last effect leads to erroneous estimates of formation temperatures and heat flows. The main aim of the research is justification of the applicability of the Ramey’s approximation model describing the thermal effect of forced fluid flows to assess the quasi-stationary effect of free thermal convection. Adaptation and verification of the model by experimental borehole temperature data. Methods: analysis of geothermal and technological parameters determining the quasi-stationary effect of free thermal convection described by the Ramey’s model; comparison of calculations based on the Ramey’s model with data from experimental studies in boreholes. Results. The application of the Ramey’s model for evaluating the quasi-stationary thermal effect of free thermal convection in water-filled boreholes has been substantiated and experimentally verified. The decrease in the measured temperature gradient in comparison with the undisturbed gradient in the surrounding rocks is localized in the upper and lower intervals of the borehole. The effect is more pronounced and intervals are wider as the convective flow velocity increases, which in its turn depends on the Rayleigh number and the borehole diameter. The effect is less dependent on the total depth of the borehole.

Sophie Germain was a reputed female mathematician, an independent academia thinker, who lived in France during the first Empire and Bourbon Restauration. She had remarkable contributions to number theory and elasticity theory and she was the first to introduce the concept of mean curvature. She was a contemporary of Gauss, Lagrange, Cauchy and Poncelet, being however neglected by the scientific community of that time. An interesting parallel with the destiny of Jane Austen is also drawn. One of her main writings was Philosophical Works, published in 1879 by Paul Ritti.

The relevance of the research. Temperature measurements in boreholes are used for solving a wide range of exploration, geophysical, environmental, hydrogeological, and geodynamic problems. The development of new temperature sensors and registration systems significantly expands the capabilities of borehole thermometry. This raises the requirements for measurement accuracy. However, these requirements often cannot be satisfied in real borehole conditions due to the influence of temperature noise caused by free thermal convection of the fluid. For effective planning of equipment and methods of temperature measurements in boreholes, it is necessary to evaluate the amplitude of temperature noise. The main aim of the research is to develop mathematical models for estimation the level of temperature noise caused by free thermal convection. Methods: statistical analysis of temperature records obtained from laboratory experiments, temperature logging and temperature monitoring in boreholes. Results. The optimal parameter for estimating temperature noise is the standard deviation of temperature fluctuations. Models of varying complexity have been developed that make it possible to estimate the amplitude of convective noise depending on the geothermal gradient, the internal radius of the borehole, and the Rayleigh number. The proposed models allow choosing the equipment and methods of temperature logging and temperature monitoring in boreholes, depending on the ratio of useful signal/temperature noise.

Being one of the older settlements in the present-day City of Belgrade, more precisely the municipality of Novi Beograd, Bežanija is a place boasting rich historical, urban planning, and architectural features. Moreover, the ethnological and anthropological study of Bežanija expands the perspectives of this urban neighbourhood, attempting to examine the current social and cultural framework of its inhabitants. This paper is based on the architectural and anthropological research conducted in the form of mapping the studied area, observation, and informal interviews with residents. On the basis of the available material, the author endeavors to show that Bežanija is nowadays almost a marginalised city toponym, due to partly indeterminate and blurred boundaries cased by the specific urban development of Novi Beograd in (post)socialist era. One of the general findings is that the local identity of the population also follows the trend, which means that people's identifying with a place of residence is differently perceived by different generations depending on changes in the architecture of the neighbourhood.