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In semiconductor device manufacturing, wafer materials may be exposed to intense light sources by optical metrology tools. The desired light fluence often needs to be maximized to levels just below the optical damage threshold of materials deposited on the wafer, such as ruthenium. We, therefore, investigate light-induced permanent structural changes to thin Ru films after exposure to single 400 nm wavelength femtosecond pulses in the fluence regime before catastrophic damage. For fluences below that where full-ablation occurs, small optical increases in the reflectivity of up to 4 % are observed in the aftermath with a weak probe beam. In this fluence regime, dark-field, scanning electron, and atomic force microscopy images reveal morphological changes such as top-level ablation, where only the top part of the ruthenium layer is ablated whereas the lower part still remains on the substrate, and nanovolcano formation. However, neither top-level ablation nor nanovolcano formation is responsible for the reflection increase. Instead, Electron Backscatter Diffraction reveals that in this low fluence regime where reflectivity increases, Ru grains melt and resolidify into larger grains, which is likely responsible for the observed reflectivity increases. This result is reminiscent of our earlier work on aluminum layers and it suggests that there may be more metals that display this behavior. [ABSTRACT FROM AUTHOR]

Rare earth doped SrTiO 3 is one of the most promising oxide materials meeting the safety and stability requirements for potential applications in thermoelectric converters. This work aims to assess the feasibility of engineering SrTiO 3 -based materials to improve their thermoelectric performance. A comparative analysis of the thermoelectric properties of Sr 0.925 Dy 0.075 TiO 3 ceramic samples obtained from preliminarily mechanically activated Sr 0.925 Dy 0.075 TiO 3 nano-powder by two methods – solid-state reaction synthesis and spark plasma sintering – was carried out. Significant differences in the morphology of the samples lead to significant differences in the temperature dependences of electrical resistivity and the Seebeck coefficient. Ceramics obtained by solid-state reaction synthesis exhibit lower porosity and lower electrical resistivity. The thermoelectric power factor of such ceramics is 2–3 times higher than that of samples obtained by spark plasma sintering. The obtained value of thermoelectric figure of merit ZT = 0.41 at T = 673 K for Sr 0.925 Dy 0.075 TiO 3 is the highest value among n-type oxide thermoelectric ceramics at a given temperature and maintains a tendency to increase with increasing temperature. [ABSTRACT FROM AUTHOR]

Major depressive disorder (MDD) is a common mental health disorder with a lifetime prevalence of 20.6% among United States (US) adults. Multiple US surveys have shown a consistently higher burden of mental health struggles among lesbian, gay, bisexual, trans, and questioning (LGBTQ+) adults compared to non-LGBTQ+ adults. However, it is not known whether diagnosis and treatment for those adults who do report symptoms of MDD differ based on sexual orientation. We test for differences in prevalence, diagnosis, and treatment of MDD in sexual minorities using appropriate multivariable logistic regression using the New York City Health and Nutrition Examination Survey (NYC HANES). About 10% of NYC adults (≥ 20 years old) self-identify as a sexual minority and 8.5% of adults in NYC have MDD based on the Patient Health Questionnaire (PHQ-9) score. Significantly higher proportion of sexual minorities in NYC have depression compared to non-sexual minorities (17.7% vs. 7.6%, p = 0.01). In the multivariable model, sexual minorities were 2.33 (CI = [1.24–4.39], p = 0.009) times more likely to have depression compared to non-sexual minorities. Additionally, people with multimorbidity were more likely to be diagnosed for depression (OR = 3.78, CI = [1.33, 10.75], p = 0.013). Disparities exist in the prevalence, diagnosis, and treatment of MDD in NYC adults. Targeted outreach toward the LGBTQ + community should be considered by public health officials when designing primary and secondary prevention programs for depression. [ABSTRACT FROM AUTHOR]

The paper studies a nonlinear equation including both fractional and ordinary derivatives. The singular Cauchy problem is considered. The theorem of the existence of uniqueness of a solution in the neighborhood of a fixed singular point of algebraic type is proved. An analytical approximate solution is built, an a priori estimate is obtained. A formula for calculating the area where the proven theorem works is obtained. The theoretical results are confirmed by a numerical experiment in both digital and graphical versions. The technology of optimizing an a priori error using an a posteriori error is demonstrated. [ABSTRACT FROM AUTHOR]

Summary: This paper proposes a sliding‐mode‐based adaptive boundary control law for stabilizing a class of uncertain diffusion processes affected by a matched disturbance. The matched disturbance is assumed to be uniformly bounded along with its time derivative, whereas the corresponding upper bounding constants are not known. This motivates the use of adaptive control strategies. In addition, the spatially‐varying diffusion coefficient is also uncertain. To achieve asymptotic stability of the plant origin in the L2$$ {L}_2 $$‐sense in the presence of the disturbance, a discontinuous boundary feedback law is proposed where the gain of the discontinuous control term is adjusted according to a gradient‐based adaptation law. A constructive Lyapunov analysis supports the stability properties of the considered closed‐loop system, yielding sufficient convergence conditions in terms of suitable inequalities involving the controllers' tuning parameters. Simulation results are presented to corroborate the theoretical findings. [ABSTRACT FROM AUTHOR]

Introduction: There is a gap in knowledge regarding development of endometriosis and adenomyosis lesions visible at transvaginal ultrasound. The objectives were to evaluate if women with symptoms suggestive of endometriosis or adenomyosis but normal ultrasound examination develop endometriosis or adenomyosis lesions visible at ultrasound over time and if alterations of symptoms over time are associated with ultrasound findings at follow‐up. Material and Methods: This was a prospective cohort study of 100 symptomatic women with normal initial ultrasound examination during 2014–2017 who underwent follow‐up ultrasound examination in 2022. Symptoms suggestive of endometriosis were assessed using visual analog scale at both examinations and minimal clinically important difference of 10 mm was considered as a significant alteration. An examiner with expertise in advanced ultrasound examination of endometriosis performed transvaginal ultrasound examinations in accordance with the consensus protocol by the International Deep Endometriosis Analysis group. Results: At follow‐up ultrasound examination of 100 women, 13 (13% [95% CI 7.1–21.2]) had visible endometriosis or adenomyosis lesions, 8 (8% [95% CI 3.5–15.2]) had endometriosis lesions, and 6 (6% [95% CI 2.2–12.6]) had adenomyosis. At follow‐up, women with endometriosis or adenomyosis lesions reported lower intensity of dysmenorrhea and chronic pelvic pain compared to women without lesions (48 mm [IQR 16–79] vs. 73 mm [IQR 46–85] and 45 mm [IQR 26–57] vs. 57 mm [IQR 36–75], p = 0.087 and p = 0.026, respectively). None of the women with endometriosis or adenomyosis lesions reported increased intensity of dysmenorrhea at follow‐up, compared to 32/86 women (37%) without lesions (p = 0.008). Increased intensity of chronic pelvic pain tended to be less common in women with lesions compared to those without (3/13 [23%] vs. 35/86 [41%], p = 0.223). Conclusions: Our findings suggest that in symptomatic women, endometriosis and adenomyosis lesions visible at ultrasound may develop over time. However, majority of women remain having normal ultrasound examinations despite symptoms. Exacerbation of dysmenorrhea or chronic pelvic pain during follow‐up was not associated with the development of endometriosis or adenomyosis lesions visible at ultrasound, suggesting that even women with less severe symptoms might benefit from a follow‐up ultrasound when indicated. [ABSTRACT FROM AUTHOR]

The article discusses the synthesis of a triterpene analog of α-phenyl-N-tert-butylnitrone, a compound with potential antioxidant properties. The synthesis involved the preparation of the analog from natural sources and detailed chemical reactions. The study aims to explore the potential therapeutic applications of the synthesized compound in treating diseases associated with oxidative stress. The research provides valuable insights into the development of novel compounds with antioxidant properties for various health conditions. [Extracted from the article]

The results of studies of a solid-state closing switch for a high-current pulse switching are presented. The experiments were carried out on a laboratory facility with a capacitive energy storage run down a discharge circuit with electrical-explosive opening switch (EEOS) by a current pulse with an amplitude ~450 kA. The discharge circuit consists of two sections separated by a branch with a solid-state closing switch. A metal foil of the EEOS can be located in an interelectrode gap of the closing switch. The operation of the EEOS leads to a breakdown of the insulation of the closing switch, as a result of which an effective shunting of the section of the discharge circuit containing the EEOS occurs. The developed combined solid-state closing switch in the future is capable of providing multi-channel switching of a high-current pulse to the load synchronously with the EEOS operation. [ABSTRACT FROM AUTHOR]

Based on a combination of molecular and morphological data, we herein report a new species within the bufonid Bufo gargarizans species complex. This is a widespread species complex with distribution from eastern Russia and the Korean Peninsula to China and the Ryukyu Islands of Japan. Records of this species have been documented in the Guangxi and Yunnan Provinces near the border with Vietnam and, for the first time from Vietnam, in Ha Giang Province. The new record of Bufo cf. gargarizans from Vietnam is from Ha Tinh Province. This species has never been reported from Vietnam so far south, about 550 km south from the previously known locality in Ha Giang Province. The female specimen was found in the Ha Tinh Province, Vu Quang National Park of central Vietnam and two specimens (male and female) were found Ha Giang Province. They are clearly distinguished from B. gargarizans and all the mentioned species by a specific color pattern on the belly and creamy-yellowish throat with large, bright red speckles. Genetic divergences of three Vietnam specimens from Ha Giang and Ha Tinh Provinces in the ND2 gene sequences between the B. sp. nov. and all other congeners ranged from 4.3% (with B. andrewsi) to 7.0% (with B. stejnegeri). We give a description of the morphological characters and coloration of the new record and provide an expanded diagnosis. [ABSTRACT FROM AUTHOR]

The existence of stationary solutions of singularly perturbed systems of reaction–diffusion–advection equations is studied in the case of fast and slow reaction–diffusion–advection equations with nonlinearities containing the gradient of the squared sought function (KPZ nonlinearities). The asymptotic method of differential inequalities is used to prove the existence theorems. The boundary layer asymptotics of solutions are constructed in the case of Neumann and Dirichlet boundary conditions. The case of quasimonotone sources and systems without the quasimonotonicity requirement is also considered. [ABSTRACT FROM AUTHOR]

The paper presents calculations of the two-stage separation of silicon isotopes in Q-cascade models. Feed flow profiles are obtained for Q-cascades, and the concentration distribution by stages is determined for silicon isotopes. It is shown that three highly-enriched (>99%) products can be obtained at a 35 g/s feed flow, namely: 32.31 g/s 28Si, 1.61 g/s 29Si, and 1.08 g/s 30Si. [ABSTRACT FROM AUTHOR]

The paper presents calculations of the process parameters of the chemical isotope exchange with a thermal flow reversal in the BF3–C6H5OCH3 system and engineering data for rectifying columns for its implementation. It is shown that the calculated parameters are in good agreement with those found the literature. The best engineering data are obtained for rectifying columns intended for the production of enriched (96 wt.% 10B enrichment) boron in the amount of 2 and 4 tons per year. [ABSTRACT FROM AUTHOR]

This study analysed long-term trawl survey data to investigate changes in the spatial distribution, range boundaries, and catch rates of the five most common shark species in the Russian waters of the northwestern Pacific. Significant alterations in the spatial distributions of these shark species were observed during the study period. The 1980s witnessed the most widespread distribution and maximum catches of salmon and blue sharks. In the 2000s, the North Pacific spiny dogfish exhibited its broadest distribution, with maximum catches recorded in the 1980s and 2010s. The Pacific sleeper shark exhibited its widest distribution in the 1980s, with maximum catches occurring in the 2000s. Shortfin mako were recorded within the study area only in the 1980s and 2010s, with maximum catches occurring in the latter period. Shifts in the range of boundaries during the study period exhibited different patterns among the species. Statistically significant shifts in boundaries were found for Pacific spiny dogfish, salmon sharks, and Pacific sleeper sharks. During the review period, salmon shark catches significantly decreased in Pacific waters and in the study area as a whole, but the reasons for this difference have not yet been determined. For the other shark species, statistically significant changes in catch size were not revealed. The observed significant changes in the spatial distribution and position of the boundaries of the ranges are likely due to both subjective reasons and climatic changes. [ABSTRACT FROM AUTHOR]

In this paper, we study the properties of trajectories of systems of ordinary differential equations generated by the velocity field of a moving incompressible viscoelastic fluid with memory along the trajectories in a domain with multiple boundary components. The case of a velocity field from a Sobolev space with inhomogeneous boundary conditions is considered. The properties of the maximal intervals of existence of solutions to the Cauchy problem corresponding to a given velocity field are investigated. The study assumes the approximation of a velocity field by a sequence of smooth fields followed by a passage to the limit. The theory of regular Lagrangian flows is used. [ABSTRACT FROM AUTHOR]

The art of light engineering unveils a world of possibilities through the meticulous manipulation of photonic properties such as intensity, phase, and polarization. Precision control over these properties finds application in a variety of fields spanning communications, light–matter interactions, laser direct writing, and imaging. Terahertz (THz) range, nestled between microwaves and infrared light, stands out for its remarkable ability to propagate with minimal losses in numerous dielectric materials and compounds, making THz imaging a powerful tool for noninvasive control and inspection. In this study, a rational framework for the design and optimal assembly of nonparaxial THz imaging systems is established. The research is centered on lensless photonic systems composed solely of high‐resistivity silicon‐based nonparaxial elements such as the Fresnel zone plate, the Fibonacci lens, the Bessel axicon, and the Airy zone plate, all fabricated using laser ablation technology. Through a comprehensive examination through illumination engineering and scattered light collection from raster‐scanned samples in a single‐pixel detector scheme, the imaging systems are evaluated via diverse metrics including contrast, resolution, depth of field, and focus. These findings chart an exciting course toward the development of compact and user‐friendly THz imaging systems where sensors and optical elements seamlessly integrate into a single chip. [ABSTRACT FROM AUTHOR]

Every year, an increasing number of scientific research projects are devoted to the problem of the use of alternative feedstock sources, as well as low-carbon energy. Special attention of researchers is paid to the problem of production of "green" hydrogen because it is a promising carbon-free alternative to conventional fuel types. However, currently, among the great variety of its production methods, there is none that meets all the requirements imposed by modern industry. In light of this, the authors perform a brief review of recent publications devoted to new production methods of "green" hydrogen from various feedstocks. [ABSTRACT FROM AUTHOR]

Gelatinous zooplankton (GZ) biomass is an important, yet often overlooked, vector of the particulate organic matter downward export and a nutritional prey source for the mesopelagic and benthic communities. To better quantify the potential impact of their blooms on biogeochemistry and food webs, we performed decomposition and sinking experiments under two different temperature regimes, 6 and 12 °C using 260 Salpa aspera, sampled in the Northeast Pacific (48.39°–50.40°N, 126.40°–145.00°W) during May 2021. Salps sank 1312 and 1424 m day−1 on average in 6 and 12 °C, respectively. The fast sinking is common among other salp species. Salp decay was exponential and occurred ~ 1.5 times faster under warmer conditions. Comparison of the published GZ decay rates supported their strong temperature dependence (Q10 = 3.46) and revealed that S. aspera decayed slower than most GZ taxa. Carcass sinking rates were higher than previously reported for this species and slowed after a prolonged decay. Biochemical (proteins, carbohydrates, lipids) and elemental (C: carbon, N: nitrogen) compositions were determined for salps at various decomposition stages. The high water content (~ 97%) and low organic content (27.8 ± 7.1% dry weight) were typical of other thaliaceans. The high C:N ratio (6.61 ± 1.14) of S. aspera, compared to many thaliaceans, suggested that their carcasses are valuable sources of carbon beyond the euphotic zone. [ABSTRACT FROM AUTHOR]

Here, we present history and modern distribution of Typha laxmannii in Ukraine, its ecological and phytocoenotic peculiarities. It is a perennial herbaceous plant, alien species of Asian origin which is currently spreading in the country. For the first time in the flora of Ukraine T. laxmannii (under the name T. stenophylla) was recorded in 1902 in the south of Ukraine (Kherson Oblast). The species is distributed almost throughout Ukraine, but with a majority of records in the central and western parts of Ukraine. The association Typhetum laxmannii formed by this species is common for Ukraine. Depending on the ecological and geographical conditions and floristic composition, 3 following variants in this association were identified: var. typica, var. T. latifola, and var. Schoenoplectus lacustris. Phytocoenoses of this association are distributed almost throughout the whole territory of Ukraine, but the ecological optimum of the species is observed in the South of the country, in the steppe zone, on slightly saline, well-watered substrates. Based on studies conducted in Zhytomyr Oblast in 1995–2021, the expansion rate of T. laxmannii was observed – from the South to the North – in average 16.6 ± 1.09 km·year−1. From the sites of the primary penetration of the species into the region (Forest-Steppe zone), the expansion rate of it toward to the North was significantly lower (7.7–9.0 km·year−1) compared to that in the Forest zone – Ukrainian Polissia (23.4–31.9 km·year−1). [ABSTRACT FROM AUTHOR]

Aquaporin-4 (AQP4) is the main water channel in the central nervous system. AQP4 is highly expressed in brain structures, suggesting its crucial role in water transport in norm and in pathology. Here, we studied the effect of a change in the drinking regimen (water deprivation, hyperhydration) and inherited arterial hypertension on the expression of the AQP4 water channel gene in the hypothalamus, a regulatory brain center of visceral functions. The expression level of the Aqp4 gene in hyperhydrated animals was found to be more than 1.5 times lower than in water-deprived animals, which may reflect the need to prevent cytotoxic edema during increased fluid intake. Rats with inherited stress-induced arterial hypertension are characterized by an increased level of the Aqp4 gene in the hypothalamus, suggesting the involvement of this channel in processes associated with the regulation of brain water balance and the prevention of vasogenic cerebral edema in arterial hypertension. Thus, the presence of the AQP4 water channel in the brain, associated with the protection of brain cells, is functionally determined by the state of the body, as evidenced by bidirectional changes in Aqp4 expression during hyperhydration and arterial hypertension. [ABSTRACT FROM AUTHOR]

Nonlinear phenomena similar to the Belousov–Zhabotinsky reaction (autocatalytic oscillations of the population of high-spin and low-spin multielectron states of a transition metal ion) in open systems with spin crossover near bistability are considered. The conditions for possible experimental observation of autocatalytic oscillations of the magnetization in magnetically ordered systems with spin crossover are analyzed. [ABSTRACT FROM AUTHOR]

Abstract—For deeply supercooled bulk water, known are anomalies of thermodynamic quantities near the Widom line, the locus of increased fluctuations of entropy and density. In this work, we measured the reflected power of microwave radiation at the frequency of 18 GHz from a silicate sorbent sample moistened with a hydrogen peroxide solution. In the experiment, we observed variations in the recorded reflected radiation power in the range of –46 to –47°C determined by structural changes in the liquid. Thus, it is shown that fluctuations of water parameters near the Widom line manifest themselves in changes not only in thermodynamic, but also in electrophysical quantities. [ABSTRACT FROM AUTHOR]

Random Hamiltonian flows in an infinite-dimensional phase space is represented by random unitary groups in a Hilbert space. For this, the phase space is equipped with a measure that is invariant under a group of symplectomorphisms. The obtained representation of random flows allows applying the Chernoff averaging technique to random processes with values in the group of nonlinear operators. The properties of random unitary groups and the limit distribution for their compositions are described. [ABSTRACT FROM AUTHOR]

The length of internodes plays a crucial role in determining the height of the castor plant (Ricinus communis L.). However, the specific mechanisms underlying internode elongation, particularly in the main stem of the castor plant, remain uncertain. To further investigate this, we conducted a study focusing on the internode tissue of the dwarf castor variety 071113, comparing it with the control high-stalk Zhuansihao. Our study included a cytological observation, physiological measurement, transcriptome sequencing, and metabolic determination. Our integrated findings reveal that the dwarf variety 071113 undergoes an earlier lignification development in the main stem and has a more active lignin synthesis pathway during internode intermediate development. In addition, the dwarf variety exhibited lower levels of the plant hormone indole-3-acetic acid (IAA), which had an impact on the development process. Furthermore, we identified specific enzymes and regulators that were enriched in the pathways of the cell cycle, auxin signal transduction, and secondary cell wall synthesis. Using these findings, we developed a model that explained the intermediate secondary growth observed in castor internode elongation and enhanced our comprehension of the dwarfing mechanism of the 071113 variety. This research provides a theoretical groundwork for the future breeding of dwarf castor varieties. [ABSTRACT FROM AUTHOR]

In this study, we present a novel and ultrasensitive magnetic lateral flow immunoassay (LFIA) tailored for the precise detection of zearalenone, a mycotoxin with significant implications for human and animal health. A versatile and straightforward method for creating non-covalent magnetic labels is proposed and comprehensively compared with a covalent immobilization strategy. We employ the magnetic particle quantification (MPQ) technique for precise detection of the labels and characterization of their functionality, including measuring the antibody sorption density on the particle surface. Through kinetic studies using the label-free spectral phase interferometry, the rate and equilibrium constants for the binding of monoclonal antibodies with free (not bound with carrier protein) zearalenone were determined to be kon = 3.42 × 105 M−1s−1, koff = 7.05 × 10−4 s−1, and KD = 2.06 × 10−9 M. The proposed MPQ-LFIA method exhibits detection limits of 2.3 pg/mL and 7.6 pg/mL when employing magnetic labels based on covalent immobilization and non-covalent sorption, with dynamic ranges of 5.5 and 5 orders, correspondingly. We have successfully demonstrated the effective determination of zearalenone in barley flour samples contaminated with Fusarium graminearum. The ease of use and effectiveness of developed test systems further enhances their value as practical tools for addressing mycotoxin contamination challenges. [ABSTRACT FROM AUTHOR]

A review of studies on the chromosome sets of Palaearctic mammals carried out by Russian karyologists and an important contribution to improving the taxonomy of mammals were made for the first time. For many mammal species, the process of speciation was associated with variability in the number and morphology of the chromosomes; therefore, the karyotypes are often used as diagnostic peculiarities of morphologically similar cryptic species (sibling species). The prospects for cytogenetic studies in the field of speciation (particularly, an enhancement of reproductive isolation, initiated by chromosomal rearrangements, by selection) are discussed. [ABSTRACT FROM AUTHOR]

The review examines the role of domestic space medicine and physiology in space exploration and emphasizes that domestic space medicine will focus on biological, physiological, and psychological aspects of humans. The main task of specialists in the field of space medicine and physiology is to prepare for future stages of manned astronautics, using existing accumulated experience, new developments, and assessing the forecast of probable events and situations that the human will inevitably encounter in this new world. [ABSTRACT FROM AUTHOR]

This document is a summary of a special issue of the International Journal of Molecular Sciences titled "Plant Biology and Biotechnology: Focus on Genomics and Bioinformatics 2.0." The issue focuses on the analysis of molecular mechanisms underlying plant adaptation to environmental changes and stress response, with an emphasis on bioinformatics methods, high-throughput sequencing, and post-genome technologies. The special issue includes eight research manuscripts that explore gene expression regulation and molecular mechanisms of plant development and stress response in various plant models. The studies cover topics such as DNA binding, genetic adaptation of forest trees, drought stress response in wheat, and karyotype construction in poplar. The issue also discusses the application of machine learning methods and artificial intelligence in plant science. Overall, the special issue provides valuable insights into the field of plant bioinformatics and its potential applications in improving crop production and sustainability. [Extracted from the article]

We consider families u = u ε , 0 of boundary layer solutions to singularly perturbed quasilinear problems of the type ε 2 (a (x , u (x) , ε) u ′ (x)) ′ = b (x , u (x) , ε) for x ∈ (− 1 , 1) , u (− 1) = u ′ (1) = 0 , and we describe the behaviour of these solution families under small regular, but nonsmooth perturbations, i.e. we show existence and local uniqueness of solutions u = u ε , δ ≈ u ε , 0 to − ε 2 (a (x , u (x) , ε) u ′ (x)) ′ + b (x , u (x) , ε) = δ g (x) for x ∈ (− 1 , 1) , u (− 1) = u ′ (1) = 0 with ε ≈ 0 and δ ≈ 0. Roughly speaking, we show the following: If g is a Dirac function, then for all small ε > 0 and δ ≥ 0 , such that δ / ε is small, those solutions exist, and ‖ u ε , δ − u ε , 0 ‖ ∞ = O (δ / ε) for δ → 0 uniformly with respect to ε. If g ∈ L 2 (− 1 , 1) , then for all small ε > 0 and δ ≥ 0 , such that δ / ε is small, those solutions exist, and ‖ u ε , δ − u ε , 0 ‖ ∞ = O (δ / ε) for δ → 0 uniformly with respect to ε. And if g ∈ L ∞ (− 1 , 1) , then for all small ε > 0 and δ ≥ 0 those solutions exist, and ‖ u ε , δ − u ε , 0 ‖ ∞ = O (δ) for δ → 0 uniformly with respect to ε. Finally we show that these asymptotic estimates are optimal. • We describe the behavior of families of boundary layer solutions to singularly perturbed problems under the influence of small regular perturbations. • The behavior is as follows: The lower the smoothness (with respect to the space variable x) of the perturbation function, the worse the rate (with respect to the perturbation parameters) of convergence of the perturbed boundary layer solution family to the unperturbed one. • We present an abstract result of implicit function theorem type, which is designed for applications to singularly perturbed ODEs and PDEs. [ABSTRACT FROM AUTHOR]

The paper presents a method for estimating the inertia tensor components of a spacecraft that has expired its active life using measurement data of the Earth's magnetic field induction vector components. The implementation of this estimation method is supposed to be carried out when cleaning up space debris in the form of a clapped-out spacecraft with the help of a space tug. It is assumed that a three-component magnetometer and a transmitting device are attached on space debris. The parameters for the rotational motion of space debris are estimated using this measuring system. Then, the known controlled action from the space tug is transferred to the space debris. Next, measurements for the rotational motion parameters are carried out once again. Based on the available measurement data and parameters of the controlled action, the space debris inertia tensor components are estimated. It is assumed that the measurements of the Earth's magnetic field induction vector components are made in a coordinate system whose axes are parallel to the corresponding axes of the main body axis system. Such an estimation makes it possible to effectively solve the problem of cleaning up space debris by calculating the costs of the space tug working body and the parameters of the space debris removal orbit. Examples of numerical simulation using the measurement data of the Earth's magnetic field induction vector components on the Aist-2D small spacecraft are given. Thus, the purpose of this work is to evaluate the components of the space debris inertia tensor through measurements of the Earth's magnetic field taken using magnetometer sensors. The results of the work can be used in the development and implementation of missions to clean up space debris in the form of clapped-out spacecraft. [ABSTRACT FROM AUTHOR]

Benthic foraminifera, carbonate microfacies identification, and geochemical analysis of the Permian intervals of Pleshet-1 and David-1 boreholes from western Israel,-allowed a determination of their time frame and tectono-sedimentary relationships, further allowing insights about the nature and regional subsurface expression of the Permian. Carbonate horizons within the mixed lithology successions, yielded foraminifera suggesting the Middle/Late Permian transition. The carbonate microfacies and related stable isotopic profiles indicate a change from siliciclastic marginal marine conditions (Saad Fm.) to fully marine platform conditions (Arqov Fm.) in a gradual marine transgression onto a segmented peneplain, and producing sedimentary facies belts striking SW–NE. A comparison of this work with previous work in southern and eastern Israel suggests that the Permian formations in Israel formed NW to SE diachronistically, by marine transgression during the Middle and the Late Permian, with maximum flooding during the Changhsingian. It appears that although not precisely defined, the regional Middle/Late Permian transition happened during a major marine transgression, characterized by a negative to positive stable isotope shift, and by apparently gradual aridization of the hinterland. The regional onset of sedimentation occurred on a marginally superficially downfaulted northwestward peneplain, subdivided tentatively into four segments with shallow half-graben structures. The three eastern segments ceased their differential movements and maintained uniform northwestward subsidence during the late Wuchiapingian–Changhsingian. The most western fourth segment had differential fault activity through the Triassic and the Jurassic, and is proposed to be placed on a transition to a proximal tectonic necking zone. [ABSTRACT FROM AUTHOR]

Theoretical and experimental studies of the magnetic field distribution in the space between two cylindrical permanent magnets with through holes in the center have been carried out. In the middle of a space measuring 2 × 2 × 2 mm3 near the symmetry axis, a magnetic field with an inhomogeneity of no more than 3% was found and one in the region of 1 × 1 × 1 mm3 with less than 1% was found. Based on the calculated and experimental results, a setup for determining the Verdet constant (V) using neodymium permanent magnets was developed and manufactured. The magneto-optical constants for samples of optical ceramics from Tb2O3 and Tb3Ga5O12 at wavelengths of 0.628 and 1.06 µm are determined. [ABSTRACT FROM AUTHOR]

Molecular and crystal structures of pyrrolo[3,2-b]lup-20(29)-ene-28-carbonitrile are determined. At 100 K single crystals of the C32H46N2 compound are orthorhombic: a = 11.5659(17) Å, b = 14.173(2) Å, c = 16.038(2) Å, V = 2629.1(7) Å3, dcalc = 1.159 g/cm3, Z = 4, space group P212121, dcryst = 1.339 g/cm3. [ABSTRACT FROM AUTHOR]

We present exactly solvable modifications of the two-matrix Zinn-Justin–Zuber model and write it as a tau function. The grand partition function of these matrix integrals is written as the fermion expectation value. The perturbation theory series is written explicitly in terms of a series in strict partitions. The related string equations are presented. [ABSTRACT FROM AUTHOR]

The task was set to obtain a composite material based on polyethylene terephthalate (PET) and carboxylated carbon nanotubes (CNTs) and evaluate its characteristics. Multiwalled CNTs with different concentrations of carboxyl groups were obtained in this work. Conditions that ensured minimal disruption of the carbon skeleton were selected. Composite material samples with a uniform distribution of modified CNTs in the polymer matrix were obtained; in particular, this led to a decrease in flammability. [ABSTRACT FROM AUTHOR]

Calcium vapor reduction of niobium oxide compounds has been studied at temperatures from 1023 to 1123 K. The adiabatic temperature of calcium reduction of niobium pentoxide (3020 K) and the Mg4Nb2O9 niobate (2525 K) has been determined by thermodynamic modeling with the TERRA software suite. We have assessed the effects of process temperature, reduction time, and precursor powder particle size on the degree of reduction, specific surface area, and pore structure of the niobium powders. [ABSTRACT FROM AUTHOR]

This paper considers the equipment and power supply schemes for urban water supply, heat supply and sewerage pumping stations. Mathematical calculations of the impact of the static and full centrifugal pumps pressure ratio on the dynamic stability of synchronous electric motors were carried out. An analysis of the influence of pump parameters and engine load on the run-down parameters and drive stability during power shutdowns was carried out. It has been theoretically proven and practically confirmed that ensuring the stability of pumping station drives and the reduction in enterprise losses during various short-term disruptions in power supply networks can be provided by means of a high-speed backup source with a response time of less than 9 ms, dynamic voltage dip compensators with a response time of less than 3 ms and uninterruptible power supply sources. [ABSTRACT FROM AUTHOR]

The existence of weak solutions of the initial-boundary value problem for the equations of motion of a viscoelastic fluid with memory along trajectories of a nonsmooth velocity field and with an inhomogeneous boundary condition is proved. The study relies on Galerkin-type approximations of the original problem followed by passage to the limit based on a priori estimates. The theory of regular Lagrangian flows is used to examine the behavior of trajectories of a nonsmooth velocity field. [ABSTRACT FROM AUTHOR]

This article studies various methods for the formation of dielectric diffusion barriers between open areas of copper and an organosilicate low-k dielectric in the subtractive method of forming a metallization system, in which metal lines are first formed, and then a low-k dielectric is deposited. Films of dense and porous organosilicate glass deposited by chemical deposition from solutions are used as a low-k dielectric. A comparison is made between AlN barrier layers formed by atomic layer deposition and SiCN barriers deposited by plasma-assisted chemical vapor deposition. The successful formation of a model structure of copper metallization using AlN barriers is demonstrated. [ABSTRACT FROM AUTHOR]

Methods of data transfer from the Oracle environment to the PostgreSQL environment with stage-by-stage organization of actions and determination of the sequence of migration are considered. The main directions for the transformation of the structure of databases, data formats and executed objects are identified. Methods for converting stored procedures and triggers written in procedural languages (PL/SQL and PL/pgSQL) are specified. Software change on nodes directly connected (associated) with the database server and minimization of downtimes during migration are considered, which allows the transfer to be performed for geographically distributed and round-the-clock functioning objects. Examples of changing the speed of query execution before and after migration are given for systems of various types. [ABSTRACT FROM AUTHOR]

Tachycardia-induced cardiomyopathy (TIC) is a reversible subtype of dilated cardiomyopathy (DCM) resulting from sustained supraventricular or ventricular tachycardia and diagnosed by the normalization of left ventricular ejection fraction (LVEF) after stable sinus rhythm restoration. The aim of this study was to determine the contribution of cardiac magnetic resonance (CMR) to the differential diagnosis of TIC and DCM with persistent atrial arrythmias in patients hospitalized for the first time with heart failure (HF) with reduced LVEF of nonischemic origin. A total of 29 patients (age: 58.2 ± 16.9 years; males: 65.5%; average EF: 37.0 ± 9.5%) with persistent atrial tachyarrhythmia and first decompensation of HF without known coronary artery diseases were included in this study. The patients successfully underwent cardioversion and were observed for 30 days. The study population was divided into groups of responders (TIC patients; N = 16), which implies achieving FF > 50% or its increase > 10% in 30 days of TIC, and non-responders (N = 13). The increase in left ventricle (LV) volumes measured using CMR was significantly higher in the non-responder group when compared with the responders (114.8 mL ± 25.1 vs. 68.1 mL ± 10.5, respectively, p < 0.05). Non-responders also demonstrated decreased interventricular septum thickness (9.1 ± 0.8 vs.11.5 ± 1.3, respectively, p < 0.05). Late gadolinium enhancement (LGE) was observed in 12 patients (41.4%). The prevalence of LGE was increased in the non-responder group (25.0% vs. 65.1%, respectively, p = 0.046). Notably, a septal mid-wall LGE pattern was found exclusively in the non-responders. Epicardial adipose tissue thickness was decreased in the non-responder group versus the TIC patients. Conclusion: Patients with TIC were found to have smaller atrial and ventricular dimensions in comparison to patients with DCM. In addition, LGE was more common in DCM patients. [ABSTRACT FROM AUTHOR]

High numerical apertures can result in distortions appearing in a single-shot image, rendering the acquisition of usable images challenging, if not outright impossible. However, in the realm of single-pixel imaging, various strategies can be employed to effectively inspect objects with an excellent resolution, contrast and brightness. Recent advancements in flat photonic components have facilitated the development of compact nonparaxial imaging systems, which show great promise, particularly in the THz range of wavelengths. These innovations hold the potential to advance fields such as communication, material inspection and spectroscopy. In this study, we delve into the imaging of semi-transparent objects with varying levels of detail. Furthermore, we introduce a nonparaxial design for a flat hyperbolical lens and evaluate its performance in these imaging scenarios, comparing it to structured illumination techniques involving Airy, Bessel, and common thin lens configurations. We present findings regarding potential improvements in imaging attributable to the nonparaxial hyperbolical lens. [ABSTRACT FROM AUTHOR]

This paper presents the final stage in the study of the analytical approximate solution to a class of nonlinear differential equations unsolvable in quadrature in the general case in the neighborhood of a perturbed value of a moving singular point. An a priori error estimation is proven. The scope of application of the analytical approximate solution is extended; the formula for calculating this scope is obtained. The proof of the theorem is based on the application of elements of differential calculus. Theoretical results are supported by numerical calculations, which validate their reliability. The authors report a numerical comparison between the results, obtained in the paper, and the findings that were published earlier. [ABSTRACT FROM AUTHOR]

We study a boundary value problem for a quasilinear reaction–diffusion–advection ordinary differential equation with a KPZ-nonlinearity containing the squared gradient of the unknown function. The noncritical and critical cases of existence of an internal transition layer are considered. An asymptotic approximation to the solution is constructed, and the asymptotics of the transition layer point is determined. Existence theorems are proved using the asymptotic method of differential inequalities, the Lyapunov asymptotic stability of solutions is proved by the narrowing barrier method, and instability theorems are proved with the use of unordered upper and lower solutions. [ABSTRACT FROM AUTHOR]

Two families of commuting Hamiltonians are constructed, parameterized by a constant matrix. The first series is new and the second is known, and in our approach follows from the first series. For the proof, we use known facts on the relations between random matrices and Hurwitz numbers, but the text is selfcontained and does not require acquaintance with previous work. [ABSTRACT FROM AUTHOR]