Vol 23, No 2 (2023)

Background and Objectives: The reproductive system of women is a subject of diverse multidisciplinary research worldwide. These are oncological diseases, infertility of an unspecified nature, ovarian cryopreservation to preserve fertility, improvement of early diagnosis of diseases, etc. Elucidation of the mechanisms of diffusion of tissue water and hyperosmotic agents in luteal phase ovarian tissues controlled by аngiogenic growth factors can bring us closer to understanding biophysical processes in general. Materials and Methods. The work used spectroscopy of diffuse reflection, a free diffusion model and the modified Bouguer–Lambert–Beer law. Results. The diffusion coefficient of 40% glucose/tissue water intothe ovariantissue ofthe luteal phase D andthe diffusion time τ have been determined, which was D = (8.6 ± 1.4)·107 cm2 /s and τ = 50.4 ± 1.7 min with a samplethickness of(0.8 ± 0.1)mm. The efficiency of optical clearing of cat ovariantissues with 40% glucose immersion has been determined. Conclusions. Studies have shown that 40%-glucose is an effective optical clearing agent for topical use in differentiating normal and pathological ovarian tissues and in clinical applications.

Background and Objectives: The processes taking place in each element of a neurogliovascular unit will have repercussions in the entire unit. Astrocytes produce arachidonic acid, and its metabolites play a key role in neurogliovascular dynamics with a possibility for bidirectional control, specifically EETs and PGE2 have a vasodilatory effect while 20-HETE acts as a vasoconstrictor. We develop a minimalistic model of model of neurogliovascular unit which takes into account the effect of arachidonic acid metabolites on the blood vessel radius, determining the blood flow and further activity of the elements. Materials and Methods: In order to test the model, we simulate two scenarios of model behavior, including an external influence leading to an increase in neuronal potassium, and an external influence on EETs. Results: We have proposed a mathematical model of the neurogliovascular unit, which accounts for IP3-dependent calcium dynamics in the astrocyte, neuronal activity, and vascular dynamics, and relies on arachidonic acid and its metabolites as vasoactive substances. Numerical simulations have demonstrated the plausibility of such a control loop involving the elements of the neurogliovascular unit and associated with the influence of arachidonic acid metabolites on vascular tone and indirectly on synaptic activity. We conclude that the model can be used for further theoretical studies of the regulatory mechanisms pertaining to cerebral perfusion.

In the literature, often the capture cross sections for spherical heavy-ions are calculated by virtue of the characteristics of the s-wave barrier: its energy, radius, and stiffness. We evaluate these quantities systematically within the framework of the double-folding model. For the effective nucleon-nucleon forces, the M3Y Paris forces with zero-range exchange part are used. The strength of this part is modified to fit the barrier energy obtained with the density-dependent finite-range exchange part. For the nucleon density, two options are employed. The first one (V-option) is based on the experimental charge densities. The second one, C-option, comes from the IAEA data base; these densities are calculated within the Hartree-Fock-Bogolubov approach. For both options, the analytical approximations are developed for the barrier energy, radius, and stiffness. The accuracy of these approximations is about 3% for the barrier energy and radius and about 10% for the stiffness. The proposed approximations can be easily used by everyoneto estimatethe capture cross sections within the parabolic barrier approximation.