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Introduction. For handling the problem of mixtures design for additive construction technologies, the paper presents the results of experimental studies of rheological behavior and production characteristics (plasticity and shape stability) of cement mixtures based on various types of fillers with different size, shape, and grade. Methods and materials. Rheological properties of 3Dprintable mixtures were investigated using squeezing rheometry methods. The constant strain rate mode of 5 mm/s was used to evaluate plasticity and the constant load rate of 5 N/s was used to evaluate form stability. Scanning electron microscopy method (Phenom XL) was used to evaluate the size-geometry characteristics of cement and filler particles. Image processing to determine particle length and width was performed using ParticleMetric software. The size and gradation of the cement and filler particles were evaluated using a laser particle size analyser “Analyzette 22”. Results and discussion. It was found that a necessary condition for the plasticity and stability of mixtures is the creation of dense spatial packing of disperse phase particles. The values of the plasticity limit rational for extrusion are ensured if the filler particles have a size comparable to cement particles and multi-size gradation. The characteristics of the fillers are not decisive for the shape stability of the mixtures. Conclusion. The numerical criteria of fillers for design of 3D-printable mixtures have been substantiated, including mean average particle diameter, particle shape factor, particle distribution constant as a characteristic of the particle size gradation.

Anthracycline-induced cardiotoxicity (AIC) has been known since the 1970s but remains relevant, mainly due to the widespread use of anthracyclines in oncological practice. Currently, AIC is viewed as a prolonged and continuous process that starts with the initial dose at molecular and cellular levels and advances, ultimately resulting in cardiomyopathy and heart failure. Many contemporary studies aim to discover methods for early detection of anthracycline-related myocardial injury. Additionally, ongoing research focuses on agents for primary prevention of AIC, examining their effectiveness, place, and timing of administration. This review aims to present the available preventive options, interconnecting them with their mechanisms of action and the mechanisms of AIC. According to current recommendations, primary prevention is indicated for high- and very high-risk patients and includes general measures to lower cardiovascular risk, neurohormonal therapy, and statins. Regular cardiology assessments are a crucial component of heart damage prevention. Evidence of mild myocardial injury (deteriorated Global Longitudinal Strain and troponin release) justifi es cardioprotective measures. Some aspects remain unanswered, including whether early cardioprotection is required, as well as the role and effi cacy of sacubitril/valsartan and sodium-glucose cotransporter 2 inhibitors (SGLT2 inhibitors) for AIC prevention. Physical activity is a promising method to reduce the cardiac damaging effects of anthracyclines.

The role of androgens and estrogens in cardiovascular disease is a subject of ongoing studies. Therefore, we aim to explore the association of testosterone (T), estradiol and their ratio with cardiovascular risk factors and severity of cardiac ischemia in male patients with acute coronary syndrome. (ACS) n = 72 and controls (n = 35) Lower values of both total and free T were found in the ACS group compared to controls (8.97 vs. 10.98 nmol/l, p = 0.001 for total T and 0.189 vs. 0.223 nmol/l, p = 0.006 for free T). Patients with myocardial infarction with ST-elevation had significantly lower T fractions compared to ACS without ST-elevation. The T to estradiol ratio was significantly lower in the ACS group compared to controls and is lowest in those with STEMI. Also, all testosterone fractions – free, bioavailable, and free T, are lower in patients with ACS compared to controls. Based on these observations a conclusion can be drawn that amore estrogenic environment is associated with ST-elevation and correlates with the severity of ACS in male patients.

In this study, Sediment Microbial Fuel Cells (SMFCs) prototypes have been developed to operate under open-air conditions and power sensors for environmental monitoring. Two SMFCs with a volume of 50 l each, consisting of two types of anodic materials – graphite and coke, were operated on-field for over a year. The electrical outputs have been recorded and compared with the measured environmental parameters such as temperature, light illumination, atmospheric pressure, humidity, etc. The statistical analysis of the obtained data shows that temperature changes between 0 and 14 °C do not affect the power achieved. On the contrary, the sunlight irradiation showed a second-order polynomial correlation with the current generated by the SMFCs, increasing the latter during the days. The cathode reactions significantly impacted the power density achieved by both explored SMFCs and the system's sustainability. The metallurgical coke is suggested to be used as an inexpensive and convenient anode material for SMFCs giving compatible results to the widely used graphite.

The European Commission's decision to approve the use of insects and their parts for human consumption caused a wave of public discussion and media interest in our country. However, the veterinary perspective on the matter seems to have remained in the shadow of the predominantly discussed ethical and moral considerations on the subject and the opinions of specialists from other fields such as technologists, nutritionists, and control authorities. This led us to consider the issue of the usage of insects as food ingredients for human consumption from the veterinarian's perspective. As a starting point, we use the knowledge about insects, normatively regulated as part of the education process during the study of veterinary medicine and acquired by veterinarians nowadays. In the course of reasoning, we compare that knowledge with the questions, which have arisen in front of the veterinary guild in connection to the input of insects into the composition of foods, and as ingredients of human nutrition, which the European bodies have officially accepted and permitted. We explored normative documents and literary sources, which could answer the question: "Does the veterinary medical profession have a place in this type of husbandry and food production in the future?"

The article presents the results of studying the mechanical properties of 3D-printed layered concrete (3DPLC), including compressive, flexural, and splitting strength. To assess them, we used a compression test with a load applied perpendicular and parallel to the printed direction; a flexural test with a load applied perpendicular to the printed direction, and a splitting test to evaluate the interlayer bond strength upon the transfer of force along the boundary surface parallel to the printing direction. The mechanical properties of reference cast concrete (CC) were evaluated in accordance with the requirements of Russian standards. We established a significant anisotropy of the mechanical properties of 3DPLC along and perpendicular to the printed layers as well as a significant reduction in all strength values compared to similar values of reference CC. The printing time gap was the determining factor in the reduction of values of the mechanical properties for 3DPLC. When it increased to 20 minutes, a critical decrease in the interlayer bond strength was observed. At the same time, a threefold drop in the strength of 3DPLC compared to similar characteristics of CC could be observed in case of a decrease in humidity and a change in temperature in the range of +(10–30) °C. The impact of the curing condition on the variability of the mechanical properties of 3DPLC depended on the particle size distribution of fillers and aggregates that determined the surface roughness of the printed layer. The range of changes in the strength of sand-based printed concrete in case of varying temperature and humidity of curing (with a similar printing time gap) was 30–70 %, and for limestone-based printed concrete it was 1.5–3 times.

We present a full-wave Maxwell-density matrix simulation tool including c-number stochastic noise terms for the modeling of the spatiotemporal dynamics in active photonic devices, such as quantum cascade lasers and quantum dot structures. The coherent light–matter interaction in such devices plays an important role in the generation of frequency combs and other nonlinear and non-classical optical phenomena. Since the emergence of nonlinear and non-classical features is directly linked to the noise properties, detailed simulations of the noise characteristics are required for the development of low-noise quantum optoelectronic sources. Our semiclassical simulation framework is based on the Lindblad equation for the electron dynamics, coupled with Maxwell’s equations for optical propagation in the laser waveguide. Fluctuations arising from the interactions of the optical field and quantum system with their reservoirs are treated within the quantum Langevin theory. Here, the fluctuations are included by adding stochastic c-number terms to the Maxwell-density matrix equations. The implementation in the mbsolve dynamic simulation framework is publicly available.

Flavoring wine with Artemisia species, together with other aromatic herbs and/or fruits, is a practice that has evolved in different parts of Bulgaria. The aromatized wine-based beverage, called pelin, is named after the Bulgarian common name for the genus Artemisia. In this paper, we present Zmeyovski pelin, the history of which dates back to the early 20th century. We employed semi-structured interviews with 15 pelin producers from the Zmeyovo village with an age span from 44 to 83 years. The relative frequency of citation for each stated taxon was recorded. We explored the changes in the plant knowledge of the pelin makers and discussed the drivers for it. From a modern perspective, pelin can be considered a functional beverage since the aromatic plants and fruits adds a variety of biologically active substances to it, thus enhancing its health benefits. We regard the consumers’ inquiry about the benefits of the added plants as a driver for mitigating the plant awareness disparity among the local community.

ABSTRACT: Introduction. As part of the task to create new materials for additive technologies, an analysis of the situation was carried out, and a problem was identified with the lack of common approaches to selecting raw material components for mixtures. Theoretical concept. Based on the approaches of fundamental structure rheology, physicochemical mechanics of disperse systems, the theory of packing of granular media, we theoretically justified the criteria requirements for the characteristics of fillers and suggested quantitative criteria for their evaluation. It was proposed to use these quantitative criteria for a preliminary comprehensive assessment of fillers when designing compositions of mixtures for 3D construction printing. Materials and methods. The characteristics of the fillers were evaluated using scanning electron microscopy with a scanning electron microscope Thermo Scientific™ Phenom™ Desktop SEM and processing of images by the ParticleMetric software package as well as using laser granulometry with a laser analyser of particles Analysette 22. Results. We assessed the cement and 5 types of fillers that had different sizes and played different roles in the formation of the mixture properties. We also identified their estimated criterial characteristics, including the average particle diameter, granulometric constant, and particle shape coefficient. Boundary values of these characteristics were determined for particles of different morphology and dispersion degree. Conclusion. Based on the application of the suggested theoretical approaches, we determined the lines of research associated with obtaining experimental patterns of the impact of the criterial characteristics of fillers on the rheological characteristics of mixtures as well as with these characteristics according to their significance and justifying the requirements for the range of quantities of fillers depending on their size, shape, and granulometry.

ABSTRACT: Introduction. As part of the solution for the problem of creating a new class of materials for building additive technologies, cement composites reinforced with high-strength fiber, this work presents the results of experimental studies of the strength of the adhesive bonding between cement matrices and reinforcing fibers with different chemical compositions, diameters, and tensile strength. Materials and methods. Rheological properties of cement systems were studied using shear and squeeze rheometry, the method of micromechanical testing for determining the strength of the adhesive bonding “cement matrix – reinforcing fiber” based on the pull-out test, which involves pulling out the fiber from the cement matrix layer; after the pull-out test for all the studied systems, the microstructure of the contact surface “cement matrix – reinforcing fiber” was assessed using a Thermo Scientific™ Phenom™ Desktop SEM scanning electron microscope; the compressive strength of hardened cement paste-samples was determined using an INSTRON Sates 1500HDS testing machine. Results and discussions. It was established that the combination of strength characteristics of matrices, fibers, and adhesive strength at their interface allowed securing the required strength characteristics of reinforced construction composites. In the “cement matrix – carbon fiber” systems, the value of adhesive strength was 9 – 11 MPa; in the “cement matrix – steel wire” systems, the value of adhesive strength was 3 – 4 MPa. Conclusions. Matrices with viscosity modifiers containing nano- and micro-sized particles of SiO2 (complex nano-sized additive and metakaolin) are reasonable options for combinations of the “cement matrix – reinforcing fiber” components. Carbon fiber and steel wire are recommended to be used as reinforcing fibers.

Background and aims: Developmental disorders such as Autism Spectrum Disorder (ASD), Attention Deficit Hyperactivity Disorder (ADHD), and Developmental Dyslexia (DD) are reported to have more visual problems, oral language difficulties, and diminished reading skills in addition to their different diagnostic features. Moreover, these conditions also have increased internal noise and probably an impaired ability of external noise filtering. The aim of the present study was to compare the reading performance of these groups in the presence of external visual noise which disrupts the automatic reading processes through the degradation of letters. Methods: Sixty-four children and adolescents in four groups, ASD, ADHD, DD, and TD, participated in the study. Two types of stimuli were used -- unrelated words and pseudowords. The noise was generated by exchanging a fixed number of pixels between the black symbols and the white background distorting the letters. The task of the participants was to read aloud the words or pseudowords. The reading time for a single letter string, word or pseudoword, was calculated, and the proportion of errors was assessed in order to describe the reading performance. Results: The results obtained showed that the reading of unrelated words and pseudowords differs in the separate groups of participants and is affected differently by the added visual noise. In the no-noise condition, the group with TD had the shortest time for reading words and short pseudowords, followed by the group with ASD, while their reading of long pseudowords was slightly slower than that of the ASD group. The noise increase evoked variations in the reading of groups with ASD and ADHD, which differed from the no-noise condition and the control group with TD. The lowest proportion of errors was observed in readers with TD. The reading performance of the DD group was the worst at all noise levels, with the most prolonged reading time and the highest proportion of errors. At the highest noise level, the participants from all groups read the words and pseudowords with similar reading speed and accuracy. Conclusions: In reading words and pseudowords, the ASD, ADHD, and DD groups show difficulties specific for each disorder revealed in a prolonged reading time and a higher proportion of errors. The dissimilarity in reading abilities of the groups with different development is most evident when the accuracy and reading speed are linked together. Implications: The use of noise that degrades the letter structure in the present study allowed us to separate the groups with ASD, ADHD, and DD and disclose specifics in the reading process of each disorder. Error type analysis may provide a basis to improve the educational strategies by appropriately structuring the learning process of children with TD, ASD, ADHD, and DD.

The work presents novel composite catalytic materials—Ni and Co deposited on Magneli phase titania—and describes their complex characterization and integration into membrane electrode assemblies to produce hydrogen by electrochemical water splitting in cells with anion exchange membranes (AEMEC). Chemical composition, surface structure, and morphology were characterized by XRD and SEM analysis. The activity in the evolution of the partial electrode reactions of hydrogen (HER) and oxygen (OER) was assessed in an aqueous alkaline electrolyte (25 wt.% KOH) using linear sweep voltammetry. The interactive role of the support was investigated and discussed. Among the tested samples, the sample with 30 wt.% Co (Co30/MPT) demonstrated superior performance in the OER. The reaction started at 1.65 V, and at 1.8 V, the current density reached 75 mA cm−2. The HER is most efficient on the sample containing 40 wt.% Ni (Ni40/MPT), where the current density reaches 95 mA at a potential of −0.5 V. The change in catalytic efficiency compared to that of the unsupported Ni and Co is due to synergism resulting from electronic interactions between the transition metal having a hyper-d-electron character and hypo-d-electron support. The pre-selected catalysts were integrated in membrane electrode assembly (MEA) using commercial and laboratory-prepared anion-conductive membranes and tested in a custom-made AEMEC. The performance was compared to that of MEA with a commercial carbon-supported Pt catalyst. It was found that the MEA with newly prepared catalysts demonstrated better performance in long-term operation (50 mA cm−2 at 1.8 V in a 60 h durability test), which, combined with the higher cost efficiency, gave credence to considering this combination of materials as promising for AEMEC applications.

In this research, a thin layer of multi-metallic non-precious catalyst is prepared by electroplating from an electrolyte bath containing Ni, Co, and Fe sulfates over pressed commercial nickel foam electrode. The composition of the deposited catalytic film and its morphology are characterized by scanning electron microscopy (SEM) with energy dispersion X-ray (EDX) techniques. The efficiency of the prepared binder-free electrodes for electrochemical water splitting is investigated in a self-designed short water electrolysis stack with zero-gap configuration of the integrated single cells and hybrid electrical connections. The separator used is a commercial Zirfon Perl 500 membrane, doped with 25% KOH. The performance of the catalyst, the single cells, and the developed electrolyzer stack are examined by steady state polarization curves and stationery galvanostatic stability tests in the temperature range 20 °C to 80 °C. The NiFeCoP multi-metallic alloy demonstrates superior catalytic efficiency compared to the pure nickel foam electrodes and reliable stability with time. The single cells in the stack show identical performance and the cumulative stack parameters strictly follow the theoretical considerations. The applied hybrid electrical connections enable scaling of both the stack voltage and the passing current, which in turn ensures flexibility with regard to the input power and the hydrogen production capacity.

Chronic lymphocytic leukemia (CLL) is one of the most common leukemias in adults. After 2000, the FDA approved drugs for its treatment with mechanisms of action different from those of the then-known cytostatics. This new therapeutic approach, employing targeted therapy, is based on a better understanding of the biology and key pathogenetic mechanisms driving the development and progression of the disease. Deletion of the long arm of chromosome 13 is one of the most frequently described cytogenetic aberrations among CLL patients, the prognostic value of which is still debated, given that part of the tumor suppressor genes are located in this chromosome. Our study aimed to investigate the frequency of deletions affecting the retinoblastoma gene (RB1) and their impact on the time to first treatment (TTFT) in untreated B-CLL patients. The cohort included 40 patients with a confirmed diagnosis of CLL and deletion of the DLEU1 gene. Fluorescence in situ hybridization (FISH) was used to determine cytogenetic aberrations affecting the DLEU1 and Rb1 genes. The difference in time to first treatment in patients with/without deletion in the Rb1 gene was determined based on the log-rank test. In our study, we found a shorter time to initiation of first treatment in patients with a deletion in the Rb1 gene. Future clinical studies, including a more significant number of patients with an isolated deletion in the Rb1 gene, would confirm or reject the importance of the mentioned aberration as a prognostic factor and the necessity of its examination in routine practice.

In many visual perception studies, external visual noise is used as a methodology to broaden the understanding of information processing of visual stimuli. The underlying assumption is that two sources of noise limit sensory processing: the external noise inherent in the environmental signals and the internal noise or internal variability at different levels of the neural system. Usually, when external noise is added to an image, it is evenly distributed. However, the color intensity and image contrast are modified in this way, and it is unclear whether the visual system responds to their change or the noise presence. We aimed to develop several methods of noise generation with different distributions that keep the global image characteristics. These methods are appropriate in various applications for evaluating the internal noise in the visual system and its ability to filter the added noise. As these methods destroy the correlation in image intensity of neighboring pixels, they could be used to evaluate the role of local spatial structure in image processing.

We present the results of experimental studies and modelling of the evaluation of the bearing capacity of hollow 3D-printed walls with the printed shell performing bearing functions. The bearing capacity of hollow 3D-printed walls was experimentally assessed depending on the ratio of the void areas and casting layers in the wall structure. It was established that in case of central loading, a 3D-printed wall with bearing casting layers can serve as a bearing wall similar to traditional types of masonry construction without filling voids with structural concrete and reinforcement. We established the value of strength reduction of hollow 3D-printed walls, which amounted to ~0.1 – 0.25 MPa per 1 % of the increased area of voids. The limit value of the hollow structure parameter was determined, which must not exceed K = 0.75 in order to ensure the bearing capacity of self-bearing and non-bearing 3D-printed walls. We obtained an experimental model of the relationship between the hollow structure parameter and the bearing capacity, which allowed predicting the bearing capacity of a 3D-printed wall under central loading. It was suggested to take into account the hollow structure parameter K when calculating the elements of unreinforced 3D-printed walls under central compression according to the first group of limit states.

We report the discovery of an S-shaped morphology of the radio galaxy J0644+1043 imaged with a 30 μ Jy beam ^−1 sensitive 525 MHz broadband (bands 3 + 4) uGMRT map. Dedicated spectroscopic observations of the host galaxy carried out with the 2 m Rozhen telescope yielded a redshift of 0.0488, giving a projected linear size of the peculiar radio structure of over 0.7 Mpc. This giant radio galaxy is powered by a black hole of mass ${4.1}_{-2.87}^{+9.39}\times {10}^{8}$ M _⊙ , from the vicinity of which emanate well-collimated and knotty jets, each ∼100 kpc long. The entire radio structure, presumably due to the effective jet precession, is less than 50 Myr old, has a power of ∼6 × 10 ^24 W Hz ^−1 at 1.4 GHz, and has observed morphological characteristics that do not strictly conform to the traditional Fanaroff–Riley (FR) FR I or FR II categories.

The utilization of renewable energy for hydrogen production presents a promising pathway towards achieving carbon neutrality in energy consumption. Water electrolysis, utilizing pure water, has proven to be a robust technology for clean hydrogen production. Recently, seawater electrolysis has emerged as an attractive alternative due to the limitations of deep-sea regions imposed by the transmission capacity of long-distance undersea cables. However, seawater electrolysis faces several challenges, including the slow kinetics of the oxygen evolution reaction (OER), the competing chlorine evolution reaction (CER) processes, electrode degradation caused by chloride ions, and the formation of precipitates on the cathode. The electrode and catalyst materials are corroded by the Cl− under long-term operations. Numerous efforts have been made to address these issues arising from impurities in the seawater. This review focuses on recent progress in developing high-performance electrodes and electrolyser designs for efficient seawater electrolysis. Its aim is to provide a systematic and insightful introduction and discussion on seawater electrolysers and electrodes with the hope of promoting the utilization of offshore renewable energy sources through seawater electrolysis.

Trastuzumab is the primary treatment for all stages of HER2-overexpressing breast cancer in patients. Though discovered over 20 years ago, trastuzumab-induced cardiotoxicity (TIC) remains a research topic in cardio-oncology. This review explores the pathophysiological basis of TIC and its clinical manifestations. Their understanding is paramount for early detection and cardioprotective treatment. Trastuzumab renders cardiomyocytes susceptible by inhibiting the cardioprotective NRG-1/HER2/HER4 signaling pathway. The drug acts on HER2-receptor-expressing cardiomyocytes, endothelium, and cardiac progenitor cells (see the Graphical Abstract). The activation of immune cells, fibroblasts, inflammation, and neurohormonal systems all contribute to the evolution of TIC. A substantial amount of research demonstrates that trastuzumab induces overt and subclinical left ventricular (LV) systolic failure. Data suggest the development of right ventricular damage, LV diastolic dysfunction, and heart failure with preserved ejection fraction. Further research is needed to define a chronological sequence of cardiac impairments to guide the proper timing of cardioprotection implementation.