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Purpose of this study — to compare the results of different tonometry methods before surgical treatment of glaucoma and in the early postoperative period.The study was conducted on a group of 50 patients (50 eyes) aged 55 to 80 years with uncompensated primary open-angle glaucoma, who were admitted to in-patient department for glaucoma surgery. Patients were examined using bidirectional applanation tonometry of the cornea performed on Ocular Response Analyzer, pneumotonometry on Canon TX-20P device, and with Icare tonometer. These studies were carried out on the day before the surgery, the next day, and 2 weeks after the operation.Significant differences in tonometry readings were revealed between all tested devices at high intraocular pressure (IOP) levels (before glaucoma surgery). Significant differences were also found in IOP values obtained with Icare tonometer in the central zone of the cornea and in the middle periphery in the nasal and temporal sectors. A significant difference between the indicators remained on the next day after surgery, except for the Icare readings. After two weeks, the tonometric parameters did not differ significantly from each other.Corneal compensated IOP (IOPcc) is the most important tonometric indicator in clinical practice because it takes into account the individual biomechanical characteristics of the patient’s cornea. When examining patients with glaucoma, the IOPcc indicator significantly differed in uncompensated IOP, which is important for determining the correct treatment tactics. When assessing the level of IOP after surgery this trend persisted, indicating a systematic underestimation of IOP level (overestimation of the effect of glaucoma surgery). The reliability of the study is confirmed by the results of measurements on unoperated fellow eyes (control).

Purpose. To develop a method for calculating a process of graphitizing modification of unsolidificated liquid-solid zone to reduce transcrystallinity of the macrostructure and the amount of cementite in the center of castings. Methodology. The duration of solidification of the castings was determined by the kinetic curves of liquidus, solidus and pouring boundary in coordinates of relative thickness of the solidified metal layer – the parametric criterion of Gulyaev. Findings. A methodology for the process of modification of the axial zone of rolling was developed, the mass and time of adding aluminum were determined according to the amount of liquid-solid phase that remains after the solidification of the working layer. On the example of a rolling roll weighing 1115 kg, 0.488 kg of aluminum was added into liquid-solid zone after the working layer solidified. Movement of aluminum to the front of crystallization is provided by centrifugal forces and adding of aluminum along the height of the roll. Originality. For the first time, the kinetic curves of liquidus, solidus and pouring boundary have been plotted in coordinates of the relative thickness of the solidified metal layer x/R and /R2 – the parametric criterion of Gulyaev for rolled cast iron alloys cooled in chill-sand molds of various sizes. A methodology was developed for calculating the process of aluminum modification of the axial zone of rolling rolls after solidification of the working layer in the barrel which was set at the pouring boundary. The amount of aluminum depends on the remains of the liquid-solid phase. Practical value. Graphitizing modification reduces transcrystallinity of the macrostructure and the amount of cementite in the axial zone of castings. A promising direction for further development is the development of new methods for manufacturing castings due to physical and mechanical effects on the two-phase zone, deoxidation and alloying of the central zones of castings.

The planning of business processes in sea transport is the foundation of transportation companies and technological projects development forecast. The calculations of business processes parameters are mainly complicated by the fact that most of the input values are stochastic ones. This is due to the specifications of technological processes and influence of a wide specter of external environment events (e. g., hydrometeorological and ice conditions) on the one hand, and market conditions (e. g., competition conditions, market agents behavior, exchange rate) on another hand. To provide the necessary level of results reliability, the calculations, that are implemented during research of specifical sea transport operations tasks (such as technological design of seaports), require to pay a great effort in experiments planning. Planning the experiments means the process of choosing the conditions, procedures and methods of experiments running. It also includes the definition of how many experiments should be provided. In other words, the purpose of experiments planning is providing the results maximum precision and reliability with minimum number of experiments. This element of research could take a whole volume in the scientific research. A method for implementing mathematical calculations with stochastic values, which allows you to define the form of the output probability distribution without Monte-Carlo method utilization, is suggested in the paper. It is proved in the paper that the output distribution is close enough to the results, which are calculated with conventional methods. At the same time, when the number of variables is small, the method requires less computational resources.

Objectives This paper describes the emergence of the scientific study of mindfulness in schools; summarizes findings of experimental research on the impacts of school-based mindfulness programs (SBMPs) on student outcomes in prekindergarten, primary, and secondary school settings (ages 4–18 years); discusses scientific limitations and wider critiques of this work; and offers suggestions for future research. Methods Public data are used to describe the emergence of science on SBMPs, the foci of this research, and the academic disciplines contributing to it. A narrative summary of scientific findings regarding the impacts of SBMPs on students, and critiques of this work, is also presented. Results Research is increasing and is primarily psychological and prevention-oriented. Evidence shows SBMPs can enhance students’ self-regulation abilities, but SBMPs’ impacts on other student outcomes at different ages are equivocal. The current research has significant limitations, and these, alongside wider critiques of the work, suggest important directions for research. Conclusions In the next generation of science, we suggest (a) improving the experimental research; (b) expanding developmental research; and (c) re-envisioning assumptions, theories, and methods in research to go “beyond all splits” towards a non-dualistic and relationally, culturally, contextually, ethically, and developmentally grounded science on mindfulness and compassion for students in schools.

In order to analyze the effectiveness of interaction of the cargo terminal operator with customs authorities and participants in foreign economic activity, a four-sector model of the network diagram of the interaction stages between participants in the transport and logistics process at the sea cargo terminal is presented in the paper; the model allows visualizing and controlling the process of aggregated relationships during cargo operations and the provision of customs services in the area of seaports activity. Calculations of works time parameters are performed on the basis of a four-sector model, in which the event is divided into four sectors, where the number of the event is indicated on the top, the early start of work is indicated on the left, the late end of work is marked in the right sector, and the number of the initial event of the previous work is indicated in the lower sector, according to which the critical path passes. At the same time, simulation modeling of the system of relations between the participants in the transport and logistics process at the sea cargo terminal is carried out. When modeling by the Monte Carlo method, a set of parametric values presented in the form of a probability distribution is used. It is noted that the operations performed in the simulation are subject to the normal distribution law, since a large number of participants are involved in the transport and logistics system. The results of the algorithm operation are presented in the form of a data array, which is a sequence of works performed during the interaction of participants in the transport and logistics process at the sea cargo terminal. One of the methods for modeling randomly distributed variables is the Box-Muller generation method. The use of the Box-Muller method in the work makes it possible to apply the fundamental law of probability transformation to obtain two independent normal variables that have a standard normal distribution. Thus, the chosen method gives a set of random numbers that have a normal distribution with zero mean and unit standard deviation. The results of simulation modeling allow us to conclude that the aggregated system of relationship between participants in the transport and logistics process, which uses the technology of preliminary declaration in order to make a decision on the early placement of goods in the inspection zone, is effective.

The object of the study were 30 sexually mature eight-month-old female rats, whose average body weight was 0.4 kg. Further calculation of the administration of feed and drugs was performed based on the body weight of the animals.

Early recognition of the risk of Alzheimer’s disease (AD) onset is a global challenge that requires the development of reliable and affordable screening methods for wide-scale application. Proteomic studies of blood plasma are of particular relevance; however, the currently proposed differentiating markers are poorly consistent. The targeted quantitative multiple reaction monitoring (MRM) assay of the reported candidate biomarkers (CBs) can contribute to the creation of a consistent marker panel. An MRM-MS analysis of 149 nondepleted EDTA–plasma samples (MHRC, Russia) of patients with AD (n = 47), mild cognitive impairment (MCI, n = 36), vascular dementia (n = 8), frontotemporal dementia (n = 15), and an elderly control group (n = 43) was performed using the BAK 125 kit (MRM Proteomics Inc., Canada). Statistical analysis revealed a significant decrease in the levels of afamin, apolipoprotein E, biotinidase, and serum paraoxonase/arylesterase 1 associated with AD. Different training algorithms for machine learning were performed to identify the protein panels and build corresponding classifiers for the AD prognosis. Machine learning revealed 31 proteins that are important for AD differentiation and mostly include reported earlier CBs. The best-performing classifiers reached 80% accuracy, 79.4% sensitivity and 83.6% specificity and were able to assess the risk of developing AD over the next 3 years for patients with MCI. Overall, this study demonstrates the high potential of the MRM approach combined with machine learning to confirm the significance of previously identified CBs and to propose consistent protein marker panels.

The effect of short-term mechanical activation in a ball mill on the thermodynamics of interaction with hydrogen and the structure of intermetallic and hydride phases was studied for a series of AB5 type alloys from the standpoint of their use as filler in metal-polymer membranes. It was found that the activation processing leads, as expected, to a decrease in the size of coherent scattering domains and an increase in the lattice strain, while the phase composition and unit cell parameters remain unaffected. Despite this, there is a significant change in the pressure-composition isotherms, a reduction of the total capacity ad the plateau region. XRD study of the hydride phases evidences smaller volume expansion of the intermetallic crystal lattice at hydrogen absorption for the alloys subjected to mechanical activation. Analysis of the obtained thermodynamic and structural data allows us to consider the mechanically activated LaNi4.8Al0.2 as the most appropriate for low-pressure and low-temperature application in the hydrogen separation composite membranes. La0.7Ce0.3Ni4.5Cu0.5 and LaNi5 with maximum activation treatment of 3 min are more promising for use at elevated pressures.

Self-heating normal domains in thin superconducting NbTiN nanostrips with the granular structure were characterized via steady-state hysteretic current–voltage characteristics measured at different substrate temperatures. The temperature dependence and the magnitude of the current, which sustains a domain in equilibrium at different voltages, can only be explained with a phonon heat capacity noticeably less than expected for 3D Debye phonons. This reduced heat capacity coincides with the value obtained earlier from magnetoconductance and photoresponse studies of the same films. The rate of heat flow from electrons at a temperature T e to phonons in the substrate at a temperature T B is proportional to ( T e p − T B p ) with the exponent p ≈ 3, which differs from the exponents for heat flows mediated by the electron–phonon interaction or by escaping of 3D Debye phonons via the film/substrate interface. We attribute both findings to the effect of grains on the phonon spectrum of thin NbTiN films. Our findings are significant for understanding the thermal transport in superconducting devices exploiting thin granular films.

An investigation is performed of the relaxation of plasma excitations in two-dimensional electron systems (2D-ESes) in GaAs/AlGaAs heterostructures. The effect radiational and incoherent collisional relaxation mechanisms have on the linewidth of cyclotron magnetoplasma resonance (CR) is studied. CR arises as a pure resonance that does not hybridize with dimensional magnetoplasma excitations. It is shown how magnetoplasma resonances form a CR’s fine structure due to the interaction between coherent radiative and incoherent collisional mechanisms of two-dimensional plasma relaxation. A comparative analysis is performed of the dependences of cyclotron and transport periods of relaxation on both the temperature and electron density of 2D-ESes. It is demonstrated that the period of cyclotron relaxation could exceed that of transport at low electron densities.

This article discusses the issues of improving hot forming technology of aviation glazing parts from organic glass using modern methods of additive technologies, relevance of development and implementation of this technology in production.

There is a lot of scientific papers that consider the efficiency of different container yard’s handling strategies. The methods of assessment vary from abstract mathematical calculations to aposterioric collection and analyses of practical data. This article deals with a new way of stacking strategy’s estimation. It postulates that investigations based on the extrapolation of existing strategies cannot be reliable due to rapid changes in terminals’ environment and restricted amount of data that can be collected within limited periods of the strategies’ application. The hypothesis of the study is that the only method that could provide robust comparative study of container stacking strategies is the simulation modelling. In the same time, any model is only a tool of analyses. The synthesis could be provided only by massive iterations of single simulation experiments with controlled searching procedure in the space of parameters. Consequently, the stress of the simulation study should be put not on the model itself, but on the way how to use it, i.e. on the experiments planning. Only a rationally constructed machine of simulation scenario generation could provide adequate and statistically reliable results. In order to demonstrate the importance of this ‘task setting’ machine, two example strategies are selected for comparison: (1) allocation of containers to slots with the minimum height and (2) stacking of containers in accordance with expected dwell time. It also shows that the objective function has a great impact on the optimal strategy implementation. In the study described in the paper the number of moves requested to select a container is opted as an optimization criterion.

The article describes the problem of the effectiveness of different container stacking strategies, which has been the matter of research in many scientific works. The methods of substantiating the strategies vary from mathematical calculations to practical application. There has been set the task to prove the adequacy of the new container stacking strategy. The application of different strategies for container terminals is found not reliable due to rapid changes of operating conditions and insufficient amount of data that can be collected for the short period of a strategy application. It is proved that the only reliable method that provides the independent proof of the efficiency of container stacking strategies is simulation modelling. Special attention in the studies should be given to planning of the experiments. To compare the strategies it is proposed to use multiple experiments with different parameters of the incoming and outgoing traffic. There is presented a case of comparison of strategies for finding a minimum over the entire stack and stacking containers based on their shelf life. When analyzing the strategies for storing containers it is necessary to determine the optimality criterion, since the attractiveness of a particular strategy will depend on the selected optimized parameter. As a criterion of optimality in the given example, the complexity of the selection of containers is taken, which is determined by the average number of movements required to select one container. It is justified that according to the optimality criterion, the best strategy takes into account the storage periods of containers.

The earliest phases of star formation are characterised by intense mass accretion from the circumstellar disk to the central star. One group of lowmass young stellar objects, FU Orionis-type stars (FUors) exhibit accretion rate peaks accompanied by bright eruptions in the optical and infrared regime. The occurance of these outbursts might solve the luminosity problem of protostars, play a key role in accumulating the final stellar mass, and have a significant effiect on the parameters of the envelope and the disk. We are performing a systematic investigation of FUors with millimeter interferometry using NOEMA and ALMA to study the outburst events and examine whether FUors represent normal young stars in exceptional times or are unusual objects. The targeted FUors show very diverse circumstellar morphologies with envelope parameters similar to those of both Class I and Class II systems, but their disks are more massive and more compact than T Tauri disks. To shed light onto the process of disk-formation, accretion, and to what role FUors play in low-mass starformation, we require the identification and light curve monitoring of as many of these stars as possible, together with the multi-wavelength and multi-scale mapping of their circumstellar environment.

The nuclear medicine phantom development is based on the step by step description of the computational and experimental biological object model. Computational phantoms are used for geometry of the object description and simulate physics of particle interactions with matter, while experimental phantoms are used for quality control tests and standardization of functional research protocols. Common examples are the dosimetry planning of radionuclide therapy and post-therapeutic scintigraphy with 131I. This review provides a list of methods for computational and experimental phantoms. Examples of existing phantoms created for the nuclear medicine tasks are also given.

The container yard is the key element of any modern container terminal. The huge amount of boxes dwelling on the operational areas of the terminals could occupy a lot of space, since one-time storage capacity of the container mega terminal handling over one million TEUs annually is something around 20 000 TEUs. The ecological pressure imposed on modern container terminal does not permit to allocate for this storage large land areas, thus forcing the box stacks grow high. The selection of the individual boxes becomes a complex and time-consuming procedure, demanding a lot of technological resources and deteriorating the service quality. The predicted combinatorial growth of redundant moves needed to clear the access to the individual container is aggravated by the well-known and widely discussed ‘sinking effect’, when containers arrived earlier are gradually covered by the ones arriving afterwards. While the random selection could be adequately assessed by combinatorial methods, the ‘sinking effect’ allows neither intuitive consideration, nor any traditional mathematical means. The only practical way to treat this problem today is in simulation, but the simulation itself causes yet another problem: the problem of model adequacy. This study deals with one possible approach to the problem designated to prove its validity and adequacy, without which the simulation has naught gnoseological value.

At design stages of any sea port development projects one of the key tasks is to estimate the amount of cargo volume to be stored on the port warehouse. The shortage of the warehouse facilities would disrupt port operations and affect the port marketing position, while the surplus capacity would raise the self-cost of the services rendered by the port. Many port developing projects and long years of operational practice have resulted into certain commonly accepted mathematical techniques that enable to assess all main parameters sufficiently accurately. With ever-growing completion between the ports worldwide, to find a delicate balance between the cost and quality becomes a core task behind nearly every aspect of port design activity. The tools that have been used for centuries in port design and development started to lose their adequacy in modern economic and logistic environment. As the response for this challenge the port designers more and more move to simulation models. In the same time, an adequate simulation models need not only accurate and reliable data, but also requests quite long time. Moreover, the models of the kind usually are created ad hoc, reflecting particular features of the primal object under development and forfeiting the generality and universality of analytical models. At beginning stages of port developing one need to have simple and easy tools for the preliminary accession of project parameters, since usually there are several variants and the full-scaled simulation of them is excluded. Still, these tools should be more enhanced sophisticated than common analytical formulae. The main drawback of the formula calculation (streaming computing by the current IT terminology) is they principally deal with deterministic values, while the real worlds is inhibited with the stochastic ones. The study represented here is an attempt to narrow this gap. The area selected to demonstrate the approach is the port warehouse size, regardless of the cargo type handled. In the same time, this technique can be spread on many other port project parameters needed to be assessed.

The single-phase multi-principal-component CoFeMnTiVZr alloy was obtained by rapid solidification and examined by a combination of electrochemical methods and gas-solid reactions. X-ray diffraction and high-resolution transmission electron microscopy analyses reveal a hexagonal Laves-phase structure (type C14). Cyclic voltammetry and electrochemical impedance spectroscopy investigations in the hydrogen absorption/desorption region give insight into the absorption/desorption kinetics and the change in the desorption charge in terms of the applied potential. The thickness of the hydrogen absorption layer obtained by the electrochemical reaction is estimated by high-resolution transmission electron microscopy. The electrochemical hydrogen storage capacity for a given applied voltage is calculated from a series of chronoamperometry and cyclic voltammetry measurements. The selected alloy exhibits good stability for reversible hydrogen absorption and demonstrates a maximum hydrogen capacity of ∼1.9 wt% at room temperature. The amount of hydrogen absorbed in the gas-solid reaction reaches 1.7 wt% at 298 K and 5 MPa, evidencing a good correlation with the electrochemical results.

The box selectivity in operational stack of container terminal is a quite common and long studied question. The pure random choice is governed by the theory of probability offering some combinatorial estimations. The introduction of operational rules like import/export separation, storage by shipping lines, sorting by rail or truck transportation etc., as well as the most notorious ‘sinking’ effect, i.e. covering of boxes arrived earlier by next cargo parties – all these blur the clear algebraiс picture and lead to appearance of many heuristic outlooks of the problem. A new impetus to this problem in last decades was given by the rapid development of IT, AI and simulation techniques. There are quite many examples of the models described in the scientific publication reflecting many real and arbitrary terminals, which embed very advanced and complicated mechanisms reflecting selected features and strategies. Unfortunately, these models usually are created ad hoc, with some pragmatic objectives and under the demand of closest possible proximity to the simulating objects. There are much less models designated to pure scientific study of the deep inner mechanisms responsible for the primal behavior of the operating container stack, enabling to introduce step by step new rules and restrictions, providing regular proving of every next stage’s adequacy and easy to use. This paper describes one attempt of this kind to create a new theoretical tool to put into the regular toolkit of the container terminal designer. The study starts with mathematical (combinatorial) considerations, proceeds with some restrictions caused by physical and technological characteristics, and ends up with the simulation model, which adequacy is confirmed by practical results.

We have investigated the spectrum of two-dimensional (2D) plasmon polaritons over the full range of magnetic fields. In our study, we investigate a disk-shaped two-dimensional electron system (2DES) with a metallic gate on the backside of the substrate. Importantly, we show that 2D plasmon polaritons hybridize with the TM$_0$ photonic mode of a dielectric waveguide formed by a sample substrate. We have developed a theory for plasmon-polaritons in an infinite 2DES. We find the experimental data to be in good agreement with the developed theory., 7 pages, 4 figures

We report on the study of phonon properties and electron-phonon coupling in thin NbTiN films, which are intensively exploited in superconducting devices. Studied NbTiN films with thicknesses less than 10~nm are disordered with respect to electron transport, the Ioffe-Regel parameter of $k_F l_e = 2.5-3.0$ ($k_F$ is the Fermi wave vector and $l_e$ is the electron mean free path), and inelastic electron-phonon interaction, the product $q_T l_e \ll 1$ ($q_T$ is the wave vector of a thermal phonon). By means of magnetoconductance and photoresponse techniques, we derived the inelastic electron-phonon scattering rate $1/\tau_{e-ph}$ and determined sound velocities and phonon heat capacities. In the temperature range from 12 to 20~K, the scattering rate varies with temperature as $1/\tau_{e-ph}\propto T^{3.45\pm0.05}$; its value extrapolated to 10~K amounts to approximately 16~ps. Making a comparative analysis of our films and other films used in superconducting devices, such as polycrystalline granular NbN and amorphous WSi, we found a systematic reduction of the sound velocity in all these films by about 50\% as compared to the corresponding bulk crystalline materials. A corresponding increase in the phonon heat capacities in all these films is, however, less than the Debye model predicts. We attribute these findings to reduced film dimensionality and film morphology.

The two major challenges in Raman spectroscopy are the low intensity of spontaneous Raman scattering and often accompanying luminescence. We overcome these two issues with a novel fiber-dispersive Raman spectrometer utilizing pulsed excitation and a superconducting nanowire single-photon detector (SNSPD). By exploiting chromatic dispersion in the fiber material, we stretched propagation times of Raman photons and performed correlated measurements in the time domain, where the two emission processes, Raman scattering and luminescence, can be effectively separated. The spectrometer greatly benefits from SNSPD metrics, i.e. broad spectral sensitivity (from UV to near-IR wavelength range) on a single-photon level and high timing resolution (small timing jitter), which outperform those of competing avalanche single-photon detectors. The spectral resolution achievable with a fiber-dispersive spectrometer for the optimized components is estimated to be as good as 3 - 10 cm