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The results of a numerical study of unstable fluid flows in the rotor of a high-speed vertical precipitation centrifuge are presented. It is shown that during the operation of a high-speed precipitation centrifuge, a qualitative change in the hydrodynamic regime is possible from conditionally laminar to conditionally turbulent, characterized by large-scale axial and radial pulsations of the liquid phase, accompanied by a significant decrease in sedimentation efficiency. It has been established that the flow pulsations are not random in nature, but the amplitude of these pulsations first increases with increasing rotation rate of the centrifuge rotor, and after passing a certain “critical” rotation rate it begins to decrease. Thus, the “critical” rotor rotation rate can be considered as a resonant rate, at which the frequency of turbulent flow pulsations (natural oscillation frequency) coincides with the rotor rotation frequency (forced oscillation frequency). The dependences of the pitch, frequency, and amplitude of liquid flow pulsations on the edge of the centrifuge overflow disk on the rotor rotation rate were obtained. It has been established that in the “subcritical” and “supercritical” operating modes, the amplitude and step of liquid pulsations on the overflow disk of the centrifuge are increasing and decreasing respectively.

The research work is devoted to the comparison of two glasses of the same composition but synthesized on different quartz materials – Tashlinsky deposit sand and Ural quartz «Crystal Mountain»), otherwise the same raw materials are used. The physicochemical properties of the obtained glasses were determined, and it was revealed that when quartz is used in glassmaking, the light transmission indicators increase. Therefore, such glasses can be classified as “especially transparent”.

A quantitative understanding of the molecular-scale mechanisms of radionuclide sorption on different clay minerals is crucial for the development and safe implementation of geological nuclear waste disposal technologies. We apply classical molecular dynamics (MD) computer simulations to study the adsorption of uranyl on the external basal surfaces of two typical clay models. In the illite model, negative charge is primarily localized in the tetrahedral sheets, while in the lower-charge smectite model, the isomorphic substitutions are introduced in the octahedral sheet. The comparison of atomic density distributions at the clay surfaces and adsorption-free energies profiles as a function of distance from these surfaces demonstrates that overall U behavior at the basal clay surface is quite similar for illite and smectite. Uranyl is sorbed as a mixture of outer-sphere aqua complexes [UO2(H2O)5]2+ and hydrolyzed aqua complexes [UO2(H2O)4–5OH]+ on both surfaces. The structural and compositional differences between the models do not greatly affect the uranyl’s nearest coordination environment and are mainly reflected in the specific localization and orientation of the uranyl ions at both surfaces and in the magnitude of the adsorption-free energies. The observed quantitative characteristics of uranyl interactions with illite and smectite surfaces will help to better understand U behavior during the sorption process on clay minerals for the entire range of mixed-layer illite–smectite structures. A comparison of two versions of the ClayFF force field in the simulations made it possible to more accurately and quantitatively evaluate some subtle features of the uranyl–clay interactions and to obtain a more precise composition of uranyl complex with the modified ClayFF force field (ClayFF-MOH).

The landscape-architectural environment represents the relationship between nature, biotechnology and architectural style, the historical-cultural cross-section of the social environment of its age. Objects of culture and art that have a special spirituality represent the historical value of the culture and traditions of living people. These include theatres, museums, historical buildings, cathedrals, and churches. Their exteriors, interiors, and landscape-architectural environment are filled with a special content than modern buildings, especially in cities. They represent the natural and cultural space of socialisation of people, especially the younger generation. The youth of the digital society receive a lot of diverse information through the Internet and other sources, where it is not always possible to check the spheres of influence on an unformed personality. Biotechnology and green technology are developing green architecture, creating an eco-friendly environment. The ecology and video ecology of the socialising environment of the city has a direct impact on the physiology, psychology, and development of a person’s own potential.

Type 2 diabetes mellitus (T2D) is a chronic metabolic disease characterized by insulin resistance and β-cell dysfunction and leading to many micro- and macrovascular complications. In this study we analyzed the circulating miRNA expression profiles in plasma samples from 44 patients with T2D and 22 healthy individuals using next generation sequencing and detected 229 differentially expressed miRNAs. An increased level of miR-5588-5p, miR-125b-2-3p, miR-1284, and a reduced level of miR-496 in T2D patients was verified. We also compared the expression landscapes in the same group of patients depending on body mass index and identified differential expression of miR-144-3p and miR-99a-5p in obese individuals. Identification and functional analysis of putative target genes was performed for miR-5588-5p, miR-125b-2-3p, miR-1284, and miR-496, showing chromatin modifying enzymes and apoptotic genes being among the significantly enriched pathways.

Current trends in neurobiological research focus on analyzing complex interactions within brain structures. To conduct relevant experiments, it is often essential to employ animals with unhampered mobility and utilize electrophysiological equipment capable of wirelessly transmitting data. In prior research, we introduced an open-source wireless electrophysiology system to surmount these challenges. Nonetheless, this prototype exhibited several limitations, such as a hefty weight for the wireless module, redundant system components, a diminished sampling rate, and limited battery longevity. In this study, we unveil an enhanced version of the open-source wireless electrophysiology system, tailored for in vivo monitoring of neural activity in rodent brains. This new system has been successfully tested in real-time recordings of in vivo neural activity. Consequently, our development offers researchers a cost-effective and proficient tool for studying complex brain functions.

We present a study of the problem of measuring ultra-low absorption in quartz materials using the time-resolved photothermal common-path interferometry (TPCI) method, which we proposed and elaborated, with allowance for developed heat diffusion in the samples. This task is related to the implementation of one of the ways of increasing the sensitivity of measurements, namely, increasing the energy of the heating pulse by increasing its duration. Analytical formulas for the time dependence of the power of the time-varying component of the probe radiation are obtained in the Gaussian approximation for the laser beams. A correction factor that takes into account the heat diffusion effect is calculated theoretically and used during calibration. The rate at which the power of the time-varying component decreases when the sample is cooled after the end of the heating pulse is calculated. When measuring in crystalline quartz, quartz glass, and also in air, the calculated rate coincided with the experimental one, which is additional evidence for the reliability of the calculations of the correction factor for calibrating the measurements. When the duration of the heating pulse is increased to 5 ms, the calculated sensitivity of the scheme for measuring absorption in quartz glasses is 2 × 10−9 cm−1.

The destruction of polymers under the influence of ultraviolet (UV) radiation is the cause of their aging and deterioration of strength properties. Asphaltenes are low-value waste products after the refining and deasphalting of heavy crude oil, which absorb UV radiation well. Asphaltenes require rational utilization, which suggests their use as UV stabilizing agents for polymers. In this work, asphaltenes were used to prevent UV aging of polypropylene (PP) by adding them in a mass fraction from 5% to 30% within an asphaltene/PP composite material. Rheometry, calorimetry, X-ray diffraction analysis, and tensile strength of PP films containing asphaltenes were performed before and after their intense UV irradiation for accelerated aging. Asphaltenes slightly reduce the viscosity, crystallinity, and mechanical strength of the initial PP due to their plasticizing effect. However, this deterioration in properties is more than compensated when studying UV-aged samples. Intense UV aging causes multiple catastrophic drops in the viscosity and strength of pure PP with the preservation of crystallinity due to the break of polymer chains and a decrease in molecular weight by approximately eight times. Asphaltenes suppress the destruction of PP, which is expressed in a significantly smaller decline in its viscosity and strength due to UV aging. The most optimal content of asphaltenes is 20%, which suppresses UV destruction by six times and best preserves the strength properties of PP.

ABSTRACTBackground:Traditional perspectives conceptualize resilience as a trait and depression as resulting from resilience deficiency. However, research indicates that resilience varies substantially even among adults who are clinically depressed, as well as across the lifespan of an individual. Few studies have investigated resilience in depression, and even fewer have examined resilience in depressed older adults. METHODS:Three hundred thirty-seven adults ≥60 years with major depressive disorder completed the Connor-Davidson Resilience Scale (CD-RISC) and measures of mental health, quality of life (QOL), and medical comorbidity. Exploratory factor analysis was used to explore the factor structure of the CD-RISC. Correlations and general linear models were used to examine associations between resilience and other variables. RESULTS:The rotated component matrix indicated a four-factor model. Sorting of items by highest factor loading revealed constructs associated with (1) grit, (2) active coping self-efficacy, (3) accommodative coping self-efficacy, and (4) spirituality. Resilience was significantly correlated with increased age, lower cognitive functioning, greater cerebrovascular risk, and greater medical comorbidity. Resilience was negatively associated with mental health symptoms (depression, apathy, and anxiety) and positively associated with QOL. The final optimal model identified less depression, less apathy, greater medical comorbidity, higher QOL, and minority (non-White) race as factors that significantly explained variability in resilience. CONCLUSIONS:Resilience was significantly associated with a range of mental health constructs in a sample of older adults with depression. Future clinical trials and dismantling studies may help determine whether interventions targeting grit, active coping, accommodative coping, and spirituality can increase resilience and help prevent and treat depression in older adults.

The article presents initial results of the project on design of the oral educational corpus containing a transcribed and annotated collection of spontaneous/unprepared speech recordings of students learning Russian as a foreign language. This article includes a literature review on design of oral corpora; a discussion on how to choose stimuli for production of spontaneous oral speech by non-native speakers; a description of the transcription experience, the classification and the summary of non-standard phonetic and communicative phenomena; the quality examination of a number of deviances which properties are impossible to investigate in the written speech. The article explores the following prosodic features typical for the oral speech of a foreign student: pauses, hesitations (voiced pauses), physiological pauses, phonetic inaccuracies, and self-corrections. The quantitative examination of the four trial speech pieces revealed the fact that the recordings do not demonstrate any differences in terms of the number of physiological pauses. However, there are significant fluctuations in the number of phonetic inaccuracies, voiced pauses and self-corrections. Comparing the above mentioned observations we identified several profiles, which reflect communicative performance of the speaker: a) the profile with a significant number of pauses indicating planning of the statement, but with a few corrections and phonetic inaccuracies; in this case the foreigner’s speech is slow but grammatically and phonetically more accurate and cohesive; b) the profile with a significant number of pauses, phonetic inaccuracies and self-corrections: the speaker has difficulties with statement planning and pronunciation; с) the profile with a few pauses and hesitations, but with a significant number of phonetic inaccuracies: the speech is quite fast, while the pronunciation is rather poor.

The article offers a new perspective of the interpretation of the poem by I. Brodsky “The Autumn cry of a hawk” (1975). If the text is traditionally considered as the realization of the theme “the poet and the crowd”, then the nostalgic motifs of “the autumn cry” are highlighted in the work. It is shown that the first years of emigration formed certain milestones in Brodsky’s mind that required “intermediate” results, and the year 1975, the third year of emigration, actualized the motives of the “native nest” in the poet’s mind. However, unlike the usual angles of homesickness, the worldview of the herobird Brodsky outgrows the limits of nostalgic feeling, but acquires the features of an ontological myth about the laws of the existence of the Universe. The motives of the individual’s fate, freedom / lack of freedom of the individual obscure the motives of homesickness in Brodsky’s text, but the latter do not disappear without a trace, but are marked with a number of “American” and “Russian” details, images, word forms. The multiplicity of geographical toponyms (Connecticut, New England, Rio Grande), the redundancy of signs of “alien” reality (13 American states, “English” speech) allow us to explicate the invisible contrast “your own and others’ ”, reinforced by the antitheses “up / down”, “heat / ice”, “North / South”. The distinct plot of the poem (the flight of a hawk to his native places) turns out to be an important semantic entourage that enhances the depth of poetic perception.

The purpose is to find out the relations of the vascular endothelium dysfunction, atherosclerotic damage to the vessels of the upper and lower limbs, the state of the antioxidant and prooxidant systems, and the lipid profile in patients with different POAG course — carriers of biological clock gene polymorphism.Materials and methods. 47 patients with advanced POAG underwent an examination that included visometry, biomicroscopy, ophthalmoscopy, perimetry, tonometry, thermometry, as well as determination of lipid metabolism, indicators of oxidative stress and antioxidant system. All patients were also tested for the degree of endothelial dysfunction by reactive hyperemia method, and the elastic properties and vascular wall tone by the volumetric sphygmomanometry method. POAG progression was determined by static automated perimetry and optical coherence tomography. The hospitalized patients were examined for daily melatonin profile and key biological clock genes typed by real-time polymerase chain reaction. The genetic material was taken by buccal scraping. Polymorphic variants were identified for CLOCK rs1801260 3111T/C and MTNR1B genes. 16 patients (S-POAG — 8, A-POAG — 8) were tested for melatonin taken from saliva samples at different times of the day in laboratory conditions with controlled nutrition and lighting using the DLMO protocol.Results. The predictors of glaucoma progression were found to be pronounced endothelial dysfunction and oxidative stress, which contribute to the acceleration of atherogenesis and a decrease in the elastic properties of the vascular wall of peripheral vessels. Clock 3111t-c circadian gene polymorphism was found to be interrelated with lipid metabolism disorders and increased lipid peroxidation in patients with POAG progression. Carriers of the G allele of the MTNR1B gene tend to have a higher level of triglyceride (TG) which grows in the evening hours if glaucoma is progressing. We showed that the phasal and amplitude characteristics of daily melatonin level, rather than its average level, may affect the state of the vascular wall of peripheral vessels in POAG patients.Conclusion. POAG progression is associated with pronounced oxidative stress, weakened antioxidant protection and dyslipoproteinemia. Differences in the lipid profile (dyslipidemia) and the indicators of oxidative stress and antioxidant protection in patients with stable and progressing glaucoma course are mutually related with Clock 3111t-c gene polymorphism (CG genotype).

In the article, based on the material of the “mystery poem” by I. Brodsky “The Procession” (1961), intertextual links are traced that allow us to penetrate into the deep layers of the poem, to see behind its plot not the story of a love disappointment (I. Romanova) or the motives of the farcical comedy dell’arte (E. Fetisova), but philosophical reflections on time, on life and death (life-death). The intertextuality in “The Procession” goes beyond literature: the compositional structure of the poem is mediated by the influence of jazz variations and blues repetitions. As a musical pretext of “The Procession”, the classic of the Leningrad dixieland “When the saints go marching in...” is attributed. According to the jazz harmony the plot of the poem is formed as a series of zongs-voices, variants-improvisations of Hamlet’s theme “To be or not to be?” (“life / death”), which in Brodsky’s poem received a subjective version: “death comes as if for the first time...” The “vortex” composition, mediated by the rhythms of jazz, allows Brodsky to lead the hero through all the circles of Dante’s “Hell”, bringing him closer to “Purgatory” in the final poem and giving him the opportunity to pass initiation, to be among the “initiates”. The hero does not reach the heights of “Paradise”, but he is granted “even breath [verse]”, explicating the idea of an eternal life march to an unattainable world harmony.

In the present study, XRD, SEM/EDS, Raman, EMR/EPR spectroscopy, and vibrating sample magnetometry (VSM) were used to analyze the reduction of hematite by the carbonization products of waste activated sludge (WAS) at 500–1000 °C. The reduction process includes the following steps: α-Fe2O3 → Fe2O3 + Fe3O4 (Ttr~500 °C) → Fe3O4 (Ttr~600–700 °C) → FeO → Feamorph. (Ttr~1000 °C). The prevalence of certain phase compositions at different hematite reduction temperatures makes it possible to predict the areas viable for the application of reduced oxides: adsorbents (after Ttr~500 °C) → soft ferromagnetic materials (after Ttr~600–700 °C) → electrically engineered amorphous iron (after Ttr~1000 °C). [ABSTRACT FROM AUTHOR]

The dynamics of rotating hydrodynamic systems containing phase inclusions are interesting due to the related widespread occurrence in nature and technology. The influence of external force fields on rotating systems can be used to control the dynamics of inclusions of various types. Controlling inclusions is of current interest for space technologies. In low gravity, even a slight vibration effect can lead to the appearance of a force acting on phase inclusions near a solid boundary. When vibrations are applied to multiphase hydrodynamic systems, the oscillating body intensively interacts with the fluid and introduces changes in the related flow structure. Asymmetries in the fluid flow lead to the appearance of an averaged force. As a result, the body is repelled from the cavity boundary and takes a position at a certain distance from it. The vibrationally-induced movement of phase inclusions in liquids can be used to improve various technological processes (for example, when degassing and cleaning liquids from solid inclusions, mixing various components, etc.). This study presents a relevant methodology to study the averaged vibrational force acting on a pair of free cylindrical bodies near the oscillating wall of a cavity. Attention is paid to the region of moderate and low dimensionless frequencies when the size of the inclusion is consistent with the thickness of the Stokes boundary layer. The dynamics of these bodies is considered in a horizontal cylindrical cavity with a fluid undergoing modulated rotation. The average lift force of a vibrational nature is measured by the method of quasi-stationary suspension of bodies whose density differs from the density of the liquid in a static centrifugal force field. The developed technique makes it possible to determine the dependence of the lift force on vibration parameters and the distance from the oscillating boundary at which solid inclusions are located. It is shown that in the region of moderate dimensionless frequencies, the average lift force acting on an inclusion near the boundary undergoing modulated rotation almost linearly depends on the dimensionless frequency. [ABSTRACT FROM AUTHOR]

Pollution by active ingredients is one of the most significant and widespread forms of pollution on Earth. Medicines can have a negative impact on ecosystems, and contamination can have unpredictable consequences. An urgent and unexplored task is to study the Lake Baikal ecosystem and its organisms for the presence of trace concentrations of active pharmaceutical ingredients. Our study aimed to conduct a qualitative analysis of active pharmaceutical ingredients, and quantitative analysis of ibuprofen in endemic amphipods of Lake Baikal, using methods of high-performance liquid chromatography and mass spectrometry (HPLC-MS). Acetylsalicylic acid (aspirin), ibuprofen, acetaminophen, azithromycin, dimetridazole, metronidazole, amikacin, spiramycin, and some tetracycline antibiotics were detected in the studied littoral amphipods. We also detected different annual loads of active pharmaceutical ingredients on amphipods. Using the multiple reaction monitoring (MRM) mode mentioned in GOST International Technical Standards, we detected molecules, fragmented as amikacin, chlortetracycline, doxycycline, oxytetracycline, dimetridazole, metronidazole and spiramycin. Thus, we first revealed that invertebrates of Lake Baikal can uptake pharmaceutical contaminants in the environment. [ABSTRACT FROM AUTHOR]