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The article develops a mathematical model of the variable flow pump of the aircraft power supply, designed to simulate the operation of the power supply depending on the speed of the sustainer engine, oil temperature, pressure and supply (removable power). In addition, a control algorithm has been developed that provides the required quality of the transient process, which is achieved by installing additional hydraulic resistances between the servo piston cavity, the drain hydraulic line and the control spool, which change the flow characteristic of the pump and contribute to the fastest attenuation of the transient process and reduce its oscillation.

Pelvic organ prolapse is a chronic disease resulting from a weakening of the musculoskeletal apparatus of the pelvic organs. For the diagnosis of this pathology, it is insufficient to conduct only a clinical examination. An effective diagnostic tool is the method of dynamic magnetic resonance imaging (MRI) of the pelvic floor, which allows a comprehensive assessment of the anatomical and functional characteristics of the walls of the pelvis and pelvic organs. The aim of the study was to analyze the literature data on the possibilities and limitations of using dynamic MRI in pelvic organ prolapse. The widespread use of the dynamic MRI method is due to the high quality of the resulting image, good reproducibility, and the maximum ability to display the characteristics of the pelvic floor. Dynamic MRI of the small pelvis allows a comprehensive assessment of the anatomical and functional features of the pelvis, excluding the effect of ionizing radiation on the body. The method is characterized by good visualization with high resolution and excellent soft tissue contrast. The method allows for assessing the state of the evacuation function of visualized structures in dynamics. Simultaneous imaging of all three parts of the pelvic floor using dynamic MRI makes it possible to assess multicompartment disorders. The anatomical characteristics of the state of the pelvic organs in the norm and in the event of prolapse are considered. The technique for performing the method and the procedure for analyzing the resulting images are described. The possibilities of diagnosing a multicomponent lesion are considered, while it is noted that dynamic MRI of the pelvic organs provides visualization and functional analysis of all three parts of the pelvis and often allows the choice and correction of tactics for the surgical treatment of pelvic organ prolapse. It is noted that dynamic MRI is characterized by a high resolution of the obtained images, and the advantage of the method is the ability to detect functional changes accompanying the pathology of the pelvic floor.

The prospect of continued manned space missions warrants an in-depth understanding of how prolonged microgravity affects the human brain. Functional magnetic resonance imaging (fMRI) can pinpoint changes reflecting adaptive neuroplasticity across time. We acquired resting-state fMRI data of cosmonauts before, shortly after, and eight months after spaceflight as a follow-up to assess global connectivity changes over time. Our results show persisting connectivity decreases in posterior cingulate cortex and thalamus and persisting increases in the right angular gyrus. Connectivity in the bilateral insular cortex decreased after spaceflight, which reversed at follow-up. No significant connectivity changes across eight months were found in a matched control group. Overall, we show that altered gravitational environments influence functional connectivity longitudinally in multimodal brain hubs, reflecting adaptations to unfamiliar and conflicting sensory input in microgravity. These results provide insights into brain functional modifications occurring during spaceflight, and their further development when back on Earth., (© 2023. The Author(s).)

Long-duration spaceflight induces changes to the brain and cerebrospinal fluid compartments and visual acuity problems known as spaceflight-associated neuro-ocular syndrome (SANS). The clinical relevance of these changes and whether they equally affect crews of different space agencies remain unknown. We used MRI to analyze the alterations occurring in the perivascular spaces (PVS) in NASA and European Space Agency astronauts and Roscosmos cosmonauts after a 6-mo spaceflight on the International Space Station (ISS). We found increased volume of basal ganglia PVS and white matter PVS (WM-PVS) after spaceflight, which was more prominent in the NASA crew than the Roscosmos crew. Moreover, both crews demonstrated a similar degree of lateral ventricle enlargement and decreased subarachnoid space at the vertex, which was correlated with WM-PVS enlargement. As all crews experienced the same environment aboard the ISS, the differences in WM-PVS enlargement may have been due to, among other factors, differences in the use of countermeasures and high-resistive exercise regimes, which can influence brain fluid redistribution. Moreover, NASA astronauts who developed SANS had greater pre- and postflight WM-PVS volumes than those unaffected. These results provide evidence for a potential link between WM-PVS fluid and SANS.

Humans undergo extreme physiological changes when subjected to long periods of weightlessness, and as we continue to become a space-faring species, it is imperative that we fully understand the physiological changes that occur in the human body, including the brain. In this study, we present findings of brain structural changes associated with long-duration spaceflight based on diffusion magnetic resonance imaging (dMRI) data. Twelve cosmonauts who spent an average of six months aboard the International Space Station (ISS) were scanned in an MRI scanner pre-flight, ten days after flight, and at a follow-up time point seven months after flight. We performed differential tractography, a technique that confines white matter fiber tracking to voxels showing microstructural changes. We found significant microstructural changes in several large white matter tracts, such as the corpus callosum, arcuate fasciculus, corticospinal, corticostriatal, and cerebellar tracts. This is the first paper to use fiber tractography to investigate which specific tracts exhibit structural changes after long-duration spaceflight and may direct future research to investigate brain functional and behavioral changes associated with these white matter pathways., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Doroshin, Jillings, Jeurissen, Tomilovskaya, Pechenkova, Nosikova, Rumshiskaya, Litvinova, Rukavishnikov, De Laet, Schoenmaekers, Sijbers, Laureys, Petrovichev, Van Ombergen, Annen, Sunaert, Parizel, Sinitsyn, zu Eulenburg, Osipowicz and Wuyts.)

Long-duration spaceflight causes widespread physiological changes, although its effect on brain structure remains poorly understood. In this work, we acquired diffusion magnetic resonance imaging to investigate alterations of white matter (WM), gray matter (GM), and cerebrospinal fluid (CSF) compositions in each voxel, before, shortly after, and 7 months after long-duration spaceflight. We found increased WM in the cerebellum after spaceflight, providing the first clear evidence of sensorimotor neuroplasticity. At the region of interest level, this increase persisted 7 months after return to Earth. We also observe a widespread redistribution of CSF, with concomitant changes in the voxel fractions of adjacent GM. We show that these GM changes are the result of morphological changes rather than net tissue loss, which remained unclear from previous studies. Our study provides evidence of spaceflight-induced neuroplasticity to adapt motor strategies in space and evidence of fluid shift-induced mechanical changes in the brain., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).)

Objective: To determine the capacities of multidetector computed tomography (MDCT) to diagnose tongue cancer., Material and Methods: Intravenous bolus contrast-enhanced MDCT was performed in 40 patients with tongue cancer diagnosed during complex clinical and instrumental examination. In all cases, the tumor had a structure of squamous cell carcinoma of varying grades. The results of MSCT were compared with the data of surgery and cytological and histological examinations. Tongue tumor accumulation of a contrast agent was qualitatively analyzed., Results: In 38 (85%) patients, the tongue tumor actively accumulated the contrast agent and was clearly differentiated in the presence of unaffected portions of the tongue and other adjacent anatomical structures, such as mouth floor, oropharynx, and larynx. Only in two cases, the tumor failed to significantly accumulate the contrast agent, which was associated with that there were massive decay areas in its structure. The sensitivity, specificity, and accuracy of MDCT in the diagnosis of tongue cancer were 95, 80, and 87.5%, respectively. MDCT could reliably differentiate changes in tongue cancer from non-tumor diseases. The result of constructing the curve of diagnostic errors became the following values: the area under the curve was 0.875 and the P-value (Asymptotic Sig.) was 0.0001., Conclusion: Intravenous bolus contrast-enhanced MDCT has a high diagnostic efficiency in identifying tongue cancer. The technique can establish the location of a tumor and to reveal the extent of the process to the nearby organs.