Search Results (66)

The MHD (magnetic hydrodynamics) boundary problem in three-dimensional domains of certain types is considered within the framework of discrete potential theory. The discrete character of the information obtained from remote sensing of the Earth and planets of the Solar System can be taken into account when using the basic principles of this theory. This approach makes it possible to reconstruct the spatial distribution of magnetic fields and the velocity field with relatively high accuracy using the heterogeneous data in some network points. In order to restore the magnetic image of a planet with a so-called dynamo, the subsequent approximations approach is implemented. The unknown physical field is represented as a sum of terms of different magnitudes. Such an approach allows us to simplify the nonlinear partial differential equation system of magnetic hydrodynamics and extend it to discrete magnetic field and velocity vectors. The solution of the simplified MHD equation system is constructed for some classes of bounded domains in Cartesian coordinates in three-dimensional space. Full article

Control charts are commonly practical as diagnostic tools in statistical applications to recognize probable changes in a process. Control charts find general use as diagnostic tools in statistics in the detection of probable shifts in a process. Among the variety of methods of detection of smaller shifts in processes, the cumulative sum (CUSUM) chart is the most useful in general use. The standard CUSUM chart is often based on the normal distribution, an assumption that does not often align with the quality characters of the majority of real processes. However, many real-world processes exhibit asymmetric and heavy-tailed behavior, which limits the performance of traditional symmetric control chart models. This study presents a new CUSUM control chart based on the inverse Maxwell (IM) distribution and terms it the IMCUSUM chart. The proposed chart’s performance is assessed based on run-length (RL) metrics, which comprise the RL average, the standard deviation of RL, and the median RL. Comparison with the existing IM exponentially weighted moving average (IMEWMA) chart is performed. The results reveal that the proposed IMCUSUM chart performs better compared with the existing IMEWMA chart, especially in the detection of small and moderate shifts in processes. The practical application of the proposed IMCUSUM chart is demonstrated with the application of the proposed and existing control charts in the survival analysis of the lifetimes of brake pads of cars. This real application example highlights the practical application of the proposed IMCUSUM chart in real processes. Full article

Background and Objective: Large language model (LLM)–based chatbots are increasingly utilized by postpartum individuals seeking guidance on breastfeeding. However, the chatbots’ content quality, readability, and alignment with clinical guidelines remain uncertain. This study was conducted to evaluate and compare the quality, readability, and factual accuracy of responses generated by three publicly accessible AI chatbots—ChatGPT-4o Pro, Gemini 2.5 Pro, and Copilot Pro—when prompted with common maternal questions related to breast-milk supply. Methods: Twenty frequently asked breastfeeding-related questions were submitted to each chatbot in separate sessions. The responses were paraphrased to enable standardized scoring and were then evaluated using three validated tools: ensuring quality information for patients (EQIP), the simple measure of gobbledygook (SMOG), and the global quality scale (GQS). Factual accuracy was benchmarked against WHO, ACOG, CDC, and NICE guidelines using a three-point rubric. Additional user experience metrics included response time, character count, content density, and structural formatting. Statistical comparisons were performed using the Kruskal–Wallis and Wilcoxon rank-sum tests with Bonferroni correction. Results: ChatGPT-4o Pro achieved the highest overall performance across all primary outcomes: EQIP score (85.7 ± 2.4%), SMOG score (9.78 ± 0.22), and GQS rating (4.55 ± 0.50), followed by Gemini 2.5 Pro and Copilot Pro (p < 0.001 for all comparisons). ChatGPT-4o Pro also demonstrated the highest factual alignment with clinical guidelines (95%), while Copilot showed more frequent omissions or simplifications. Differences in response time and formatting quality were statistically significant, although not always clinically meaningful. Conclusions: ChatGPT-4o Pro outperforms other chatbots in delivering structured, readable, and guideline-concordant breastfeeding information. However, substantial variability persists across the platforms, and none should be considered a substitute for professional guidance. Importantly, the phenomenon of AI hallucinations—where chatbots may generate factually incorrect or fabricated information—remains a critical risk that must be addressed to ensure safe integration into maternal health communication. Future efforts should focus on improving the transparency, accuracy, and multilingual reliability of AI chatbots to ensure their safe integration into maternal health communications. Full article

In this paper, we consider the fourth hybrid power mean involving two-term exponential sums and third-order character sum modulo p, a topic of significant importance in analytic number theory. These results generalize prior research, and provide new insights for studying the relationship between character sums and exponential sums. Full article

The paper examines the integration of virtue epistemology into the philosophy of science, emphasizing its potential to deepen our understanding of scientific inquiry. The article begins by considering the limitations of traditional epistemological frameworks that focus on beliefs. The discussion is set in the context of the “value turn” in contemporary epistemology. Arguments are made to move towards recognizing the significance of intellectual virtues and the nature of epistemic agents. The current gaps in definitions of intellectual virtues about reliabilist and responsibilist approaches are examined and conceptual steps are proposed to bridge these gaps. It is suggested that the local and general epistemic goals of science should be clearly distinguished and then different ways of knowing should be attributed to these goals. These ways of knowing are proposed to be seen as exemplifying the realization of reliable skills and intellectual character traits. In sum, the article argues that adopting a virtue epistemology not only enriches the discourse on scientific knowledge but also promotes a culture of responsibility and integrity in the scientific community. Full article

The aim of this study was to compare the physical, sensorial, and microstructural properties of selected meat products with their plant-based alternatives to assess how closely the alternatives mimic the original products. Six meat analogue products, including Frankfurter sausage (SuA), steak (StA), Hungarian sausage (KA), minced meat (MA), salami (SaA), and burger (BA), were compared with their corresponding meat products (SuM, StM, KM, MM, SaM, and BM, respectively). The study measured colour indicators, texture parameters, sensory attributes, and microstructural properties. The redness values (a*) of the external surfaces of SuM and KM, as well as the hardness of MM, were similar to those of their alternative products, with no statistically significant differences (p > 0.05). Sensory evaluation revealed similar ratings for two attributes: product similarity and overall appearance. However, significant differences were found in the descriptors for animal character and meat taste. Full article

For a Chevalley group $G$ over an algebraically closed field $K$ of characteristic $p>0$ with the irreducible root system $R,$ Lusztig’s character formula expresses the formal character of a simple $G$-module by the formal characters of the Weyl modules and the values of the Kazhdan–Lusztig polynomials at 1. It is known that, for a sufficiently large characteristic $p$ of the field $K,$ Lusztig’s character formula holds. The known lower bound of the characteristic $p$ is much larger than the Coxeter number $h$ of the root system $R.$ Observations show that for simple modules with restricted highest weights of small Chevalley groups such as those of types $A_1,A_2,A_3,B_2,B_3$, and $C_3$, Lusztig’s character formula holds for all $p\ge h$. For large Chevalley groups, no other examples are known. In this paper, for $G$ of type $A_l,$ we give some series of simple modules for which Lusztig’s character formula holds for all $p\ge h$. Using this result, we compute the cohomology of $G$ with coefficients in these simple modules. To prove the results, Jantzen’s filtration properties for Weyl modules and the properties of Kazhdan–Lusztig polynomials are used. Full article

A variational heteroencoder based on recurrent neural networks, trained with SMILES linear notations of molecular structures, was used to derive the following atomic descriptors: delta latent space vectors (DLSVs) obtained from the original SMILES of the whole molecule and the SMILES of the same molecule with the target atom replaced. Different replacements were explored, namely, changing the atomic element, replacement with a character of the model vocabulary not used in the training set, or the removal of the target atom from the SMILES. Unsupervised mapping of the DLSV descriptors with t-distributed stochastic neighbor embedding (t-SNE) revealed a remarkable clustering according to the atomic element, hybridization, atomic type, and aromaticity. Atomic DLSV descriptors were used to train machine learning (ML) models to predict ¹⁹F NMR chemical shifts. An R² of up to 0.89 and mean absolute errors of up to 5.5 ppm were obtained for an independent test set of 1046 molecules with random forests or a gradient-boosting regressor. Intermediate representations from a Transformer model yielded comparable results. Furthermore, DLSVs were applied as molecular operators in the latent space: the DLSV of a halogenation (H→F substitution) was summed to the LSVs of 4135 new molecules with no fluorine atom and decoded into SMILES, yielding 99% of valid SMILES, with 75% of the SMILES incorporating fluorine and 56% of the structures incorporating fluorine with no other structural change. Full article

This essay examines Matthew’s depiction of both the spirituality demonstrated by Jesus’ actions and words (his own spirituality) and the spirituality he preaches (prescribes/expects of others). Key Matthean themes interweave in this topic. Jesus’ own spirituality and that which he expects of his followers are shaped most profoundly by the apocalyptic expectation of the imminent Reign of God. All practices and attitudes must be aligned with this coming reality. Because of this, the key mark of a true disciple or righteous person is integrity—the congruence of one’s inner character and outer actions, of one’s professed commitments and one’s behaviors. In this, Jesus is the paragon of integrity: everything he does is in alignment with the character of the coming Reign and God’s will. His actions are always a manifestation of his inner character as God’s son and messianic agent within God’s emerging Reign. Those who, like Jesus, manifest a character that is aligned with the realities of the coming age are called righteous and, at the judgment, are allowed to experience God’s Reign. Their attitudes and behaviors have shown that their inner character is in alignment with the character of the Reign of God. By contrast, the scribes and Pharisees are continually upbraided for their hypocrisy and warned that this will cause them to be barred from the Reign. Thus, the spirituality of Jesus in Matthew can be summed up as “spiritual integrity” (which is “righteousness”) shaped by the character of the imminent Reign of God. Jesus exemplifies this and calls his followers to demonstrate their character with integrity as well. Full article

Aluminum-incorporated medium-manganese steel (MMnS) has potential for lightweight transport applications owing to its impressive mechanical properties. Increasing the austenite volume fraction and making microstructural changes are key to manufacturing MMnS. However, the grain boundary character and strain distribution of intercritically annealed low-density MMnS have not been extensively scrutinized, and the effects of crystallographic texture orientation on tensile properties remain ambiguous. Therefore, in this study, the microstructure, microtexture, strain distribution, and grain boundary characteristics of a hot-rolled medium-Mn steel (Fe–0.2 C–4.3 Al–9.4 Mn (wt%)) were investigated after intercritical annealing (IA) at 750, 800, or 850 °C for 1 h. The results show that the 800 °C annealed sample exhibited the highest austenite volume fraction among the specimens (60%). The duplex microstructure comprised lath-type γ-austenite, fine α-ferrite, and coarse δ-ferrite. As the IA temperature increased, the body-centered cubic phase orientation shifted from <001> to <111>. At higher temperatures, the face-centered cubic phase was oriented in directions ranging from <101> to <111>, and the sums of the fractions of high-angle grain boundaries and coincidence–site–lattice special boundaries were significantly increased. The 800 °C annealed sample with a high austenite content and strong γ-fiber {111}//RD orientation demonstrated a noteworthy tensile strength (1095 MPa) and tensile elongation (30%). Full article

Among various non-covalent interactions, selenium-centered chalcogen bonds (SeChBs) have garnered considerable attention in recent years as a result of their important contributions to crystal engineering, organocatalysis, molecular recognition, materials science, and biological systems. Herein, we systematically investigated π–hole-type Se∙∙∙O/S ChBs in the binary complexes of SeO₂ with a series of O-/S-containing Lewis bases by means of high-level ab initio computations. The results demonstrate that there exists an attractive interaction between the Se atom of SeO₂ and the O/S atom of Lewis bases. The interaction energies computed at the MP2/aug-cc-pVTZ level range from −4.68 kcal/mol to −10.83 kcal/mol for the Se∙∙∙O chalcogen-bonded complexes and vary between −3.53 kcal/mol and −13.77 kcal/mol for the Se∙∙∙S chalcogen-bonded complexes. The Se∙∙∙O/S ChBs exhibit a relatively short binding distance in comparison to the sum of the van der Waals radii of two chalcogen atoms. The Se∙∙∙O/S ChBs in all of the studied complexes show significant strength and a closed-shell nature, with a partially covalent character in most cases. Furthermore, the strength of these Se∙∙∙O/S ChBs generally surpasses that of the C/O–H∙∙∙O hydrogen bonds within the same complex. It should be noted that additional C/O–H∙∙∙O interactions have a large effect on the geometric structures and strength of Se∙∙∙O/S ChBs. Two subunits are connected together mainly via the orbital interaction between the lone pair of O/S atoms in the Lewis bases and the BD*(OSe) anti-bonding orbital of SeO₂, except for the SeO₂∙∙∙HCSOH complex. The electrostatic component emerges as the largest attractive contributor for stabilizing the examined complexes, with significant contributions from induction and dispersion components as well. Full article

Recognizing the vital role of a positive city image in attracting stakeholders, urban officials are increasingly implementing cultural branding strategies to establish and highlight their city’s distinct character. Culture, essential in urban development, shapes identity and local economy, encouraging social cohesion and sustainability. According to existing research, strategies for branding places—and cities in particular—through arts and culture include associating them with a famous personality (such as Barcelona’s perceived connection with Gaudi), flagship buildings (like Paris with the Eiffel Tower) and hallmark events (as exemplified by Cannes and its Film Festival). The European Capital of Culture awarded annually by the European Union, which associates a city with a good cultural reputation, was a favorable starting point for this research. Fourteen EcoC Bidbooks brought forward by candidate cities bidding for the title within the 2020–2026 time frame were analyzed in order to investigate essential components of city branding. The study delves into aspects such as perceived image of European Capital of Culture candidates, problems behind this perceived image and ideal city image, revealing recurrent themes that define cultural European cities today. In addition, the research identifies new strategies that complete Ashworth’s list (such as culture tailored to a particular natural environment, alternative spaces turned into culture hubs, artistic transportation, historical moments and movements, culture gamification, grassroots culture, culture thematization, highlighting the cultures of minorities, cultural fusions and embracing local folklore and mythical creatures). This helps bridge a gap in the specialized literature on cultural place branding. The study’s originality extends to the analysis of Ecoc Bidbooks as a sum of cultural branding strategies proposed by the candidate cities. Each Bidbook is in fact a cultural vision of the city under optimum financial circumstances, thereby carrying a significant weight in the realm of research. Full article

The migration of heavy metals and radionuclides is interrelated, and this study focusses on the interaction and complex influence of various toxicants. The rehabilitation of radioactively contaminated territories has a complex character and is based on scientifically supported measures to restore industrial, economic, and sociopsychological relations. We aim for the achievement of pre-emergency levels of hygienic norms of radioactive contamination of output products. This, in its sum, allows for further economic activity in these territories without restrictions on the basis of natural actions of autoremediation. Biosorption technologies based on bacterial biomass remain a promising direction for the remediation of soils contaminated with radionuclides and heavy metals that help immobilise and consolidate contaminants. A comprehensive understanding of the biosorption capacity of various preparations allows for the selection of more effective techniques for the elimination of contaminants, as well as the overcoming of differences between laboratory results and industrial use. Observation and monitoring make it possible to evaluate the migration process of heavy metals and radionuclides and identify regions with a disturbed balance of harmful substances. The promising direction of the soil application of phosphogypsum, a by-product of the chemical industry, in bioremediation processes is considered. Full article

Weather has significant impact on plant growth and development. It is important to analyze the influence of changing climate conditions on the expression of plant agronomic characters. Two flax varieties were grown from 1987 to 2018 in the Northwest of Russia. Weather conditions and their influence on flax agronomic characters were analyzed using the variance and correlations analyses. Significant influence of conditions of a particular year on the manifestation of all evaluated characters was revealed. Starting from June, high temperatures accelerate plant development at all stages. Prolongation of the germination-flowering period is most important for improving fiber productivity, while fast ripening in hot weather after flowering is preferable for the formation of high-quality fiber. Such data give a possibility to predict the yield amount and quality. The use of weather conditions data also makes possible a comparison of the results obtained in different years. The suggested method of classifying meteorological conditions of a year can be used in other genebanks for systematizing and analyzing the results of crop evaluation in the field. The correlation analysis revealed 3 correlated pleiades, namely (1) of productivity, (2) of fiber quality and yield, and (3) of the growing season phase durations, the sums of active temperatures and precipitation during each period. The great influence of growing conditions on the economically valuable traits indicates the necessity of searching for genotypes with stable character manifestations for breeding new varieties with stable yields and good fiber quality. Full article

This paper presents a mathematical model for stacks of direct methanol fuel cells (DMFCs) using an optimised method. In order to reduce the sum of squared errors (SSE) in calculating the polarisation profile, the suggested technique makes use of simulated experimental data. Given that DMFC is one of the viable fuel cell choices, developing an appropriate model is essential for cost reduction. However, resolving this issue has proven difficult due to its complex and highly nonlinear character, particularly when adjusting the DMFC model to various operating temperatures. By combining the algorithm and the objective function, the current work introduces a novel method called LSHADE (ELSHADE) for determining the parameters of the DMFC model. This technique seeks to accurately identify DMFCs’ characteristics. The ELSHADE method consists of two stages, the first of which is controlled by a reliable mutation process and the latter by a chaotic approach. The study also recommends an improved Newton–Raphson (INR) approach to deal with the chaotic nature of the I-V curve equation. The findings show that, when used on actual experimental data, the ELSHADE-INR technique outperforms existing algorithms in a variety of statistical metrics for accurately identifying global solutions. Full article