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Perceptual learning theory suggests that perceptual grouping in mathematical expressions can direct students' attention toward specific parts of problems, thus impacting their mathematical reasoning. Using in-lab eye tracking and a sample of 85 undergraduates from a STEM-focused university, we investigated how higher-order operator position (HOO; i.e., multiplication/division operators and the presence of superfluous brackets impacted students' time to first fixation to the HOO, response time, and percent of correct responses). Students solved order-of-operations problems presented in six ways (3 HOO positions × presence of brackets). We found that HOO position and presence of superfluous brackets had separate and combined impacts on calculating arithmetic expressions. Superfluous brackets most influenced undergraduates' performance when higher-order operators were located in the center of mathematical expressions. Implications for learning and future directions are discussed about observing eye movements and gaining insights into students' processes when solving arithmetic expressions.

The human body’s ultra-high field magnetic resonance imaging suffers from the inhomogeneity of the radio frequency magnetic field $B_{1}^{+}$ and the high-peak levels of SAR created in body tissues during transmission. Both issues are typically addressed in the research domain using a tight-fit local array of antenna elements attached to the body and driven with customized phases by multiple transmit channels. The same approach faces difficulties in fast and reliable SAR evaluation, precise positioning, and patient comfort in the clinical environment. Recently, a novel bore-integrated array of stripline antenna elements with substantial free space was introduced for whole-body imaging at 7 T, showing, however, insufficient transmission efficiency (the level of $B_{1}^{+}$ at the unit input power). This work aims to improve the efficiency of the bore-integrated array configuration, which, unlike the tight-fit configuration, may be beneficial for prospective clinical workflow. After analyzing the proposed solutions, particularly the stripline antenna arrays, we found that one of the main limitations is the high level of losses within the array element. We propose using patch antenna elements separated by compact dual-loop decoupling resonators to overcome this limitation. Comparing the proposed elements with striplines in the same bore-integrated eight-channel configuration, we demonstrate numerically and experimentally on the bench a transmit efficiency improvement at least 3 times depending on the excitation mode. Furthermore, the proposed array is shown to overcome both the stripline array and volumetric TEM coil in terms of SAR efficiency approaching the level of the state-of-the-art tight-fit array of fractionated dipole antennas. Our results support the feasibility of integrating multichannel transmit array coils into the bore liner of a 7 T system while compromising transmit efficiency and providing competitive SAR efficiency.

Well-being, including family well-being, is an important category both from the point of view of social policy goals and from the position of social work practice. In the conditions of serious transformations in the sphere of marriage and family and increasing social problems related to the functioning of this social institution, diversity of family situations and complication of relations between the family and the state, the issues related to family and child assistance are actualized, and, therefore, the issues of conceptualization of the notions of “well-being family”, “family disadvantage”, criteria for their definition, tools for identification both within the legal field and the practice of work with families and children.Purpose and methods. In the article on the basis of the analysis of normative documents of federal and regional levels (n = 14) and materials of the author’s research by the method of semi-formalized interview with specialists of the family assistance system in Nizhny Novgorod region (n = 7) the concepts of family well-being and dysfunction are defined.Results and conclusions. The uncertainty of the situation in which specialists work is emphasized. The concept of “well-being” in the conceptual space of the legal field is understood as a unity of functional and structural criteria, which, given the changes in the institution of the family, is increasingly rare. On the other hand, the term “dysfunctional” family is disclosed through the prism of a number of concepts identified on the basis of either objective criteria or situations that are not yet clearly describable. In these circumstances, professionals act intuitively, based on their experience and perception of the situation. “Disadvantage” is reduced to extreme and obvious forms, and the focus of work shifts to social protection institutions, when the choice of family and specialists is already limited. At the same time, informants emphasize the importance of not so much structural and objective criteria as the nature of relationships in the family, for the definition of which the practice of social work has not yet developed clear criteria, which limits the possibilities of primary/secondary prevention.

Background. The phenotypic structure of Lupinus angustifolius L. is dynamically expanding due to genetic recombinations and mutagenesis. Therefore, the existing concepts of the inflorescence color diversity in narrowleaf lupine need regular updating.Materials and methods. Research materials consisted of 887 narrowleaf lupine accessions from the VIR collection. Their morphological descriptions were made in 2009–2023 during field trials under the conditions of Moscow Province, Russia. Longterm observations made it possible to evaluate probable color modifications in inflorescences under varying weather conditions.Results. The lupine gene pool was divided into 15 biotypes differing in the anthocyanin pigmentation of separate inflorescence parts, such as the vexillum, wings, and keel, as well as the inflorescence axis. Individual color features of cotyledons, leaves, stem, and seeds also characterized the biotypes. Phenotypic characteristics of lupine biotypes were compared with diagnostic traits of intraspecific taxa and known genes for flower color.Conclusion. Three new varieties and six new subvarieties were marked out for narrowleaf lupine. Probable carriers of genes responsible for the flower’s basic color: roseus (fco 1), violaceus (fco 3), albus (fco 4), and leucospermus (fco 21, fco 22), and its modifications: Supercoeruleus, dispersus, discolor, and albiflorus, were identified. Descriptions of some biotypes failed to agree with the data on any known gene’s phenotypic expression, which attested to the presence of new mutations, recombinations, or unstudied gene associations.

Abstract Though neural machine translation (NMT) has become the leading machine translation (MT) paradigm, its output may still contain errors. To improve NMT quality, it is important to investigate these errors and to see how NMT quality changes with time. The primary focus of the paper is on what is referred to here as “temporal (in)stability of NMT”, the phenomenon that was uncovered in a year-long experiment and may be researched applying interval evaluation methods. The paper presents data collected while observing how far, if at all, the Google’s Neural Machine Translation (GNMT) system progressed during a year. The data were qualitatively evaluated based on a set of indicators. To that end, 250 Russian text sentences were chosen. In the course of a year, each sentence was repeatedly translated into French using the GNMT engine (with a time step of 1 month). The produced translations were recorded and annotated in an especially designed supracorpora database, allowing to register a series of 12 translations for each of the 250 Russian sentences. To annotate the translations, there was a need to elaborate an error typology that would help reveal if the NMT system improved its output quality or not. One year-long experiment shows that not only does NMT quality improve, but it also may decrease with time.

Abstract The role of the immune system in regulating tissue stem cells remains poorly understood, as does the relationship between immune-mediated tissue damage and regeneration. Graft vs. host disease (GVHD) occurring after allogeneic bone marrow transplantation (allo-BMT) involves immune-mediated damage to the intestinal epithelium and its stem cell compartment. To assess impacts of T-cell-driven injury on distinct epithelial constituents, we have performed single cell RNA sequencing on intestinal crypts following experimental BMT. Intestinal stem cells (ISCs) from GVHD mice have exhibited global transcriptomic changes associated with a substantial Interferon-γ response and upregulation of STAT1. To determine its role in crypt function, STAT1 has been deleted within murine intestinal epithelium. Following allo-BMT, STAT1 deficiency has resulted in reduced epithelial proliferation and impaired ISC recovery. Similarly, epithelial Interferon-γ receptor deletion has also attenuated proliferation and ISC recovery post-transplant. Investigating the mechanistic basis underlying this epithelial response, ISC STAT1 expression in GVHD has been found to correlate with upregulation of ISC c-Myc. Furthermore, activated T cells have stimulated Interferon-γ-dependent epithelial regeneration in co-cultured organoids, and Interferon-γ has directly induced STAT1-dependent c-Myc expression and ISC proliferation. These findings illustrate immunologic regulation of a core tissue stem cell program after damage and support a role for Interferon-γ as a direct contributor to epithelial regeneration.

Objective: To investigate the effectiveness of radiological methods for diagnosing optic nerve and chiasm atrophy in compressive optic neuropathy caused by tumors of the chiasmal-sellar region (CSR). Material and methods: The diagnostic and treatment outcomes of 50 patients (100 eyes) with CSR tumors were analyzed. These patients were treated at the A.P. Romodanov Institute of Neurosurgery of the National Academy of Medical Sciences of Ukraine from 2021 to 2023. The study group of patients (50 patients) was divided into two subgroups: Group I – restoration of visual functions (26 patients, 52%, 52 eyes); Group II – no restoration of visual functions (24 patients, 48%, 48 eyes). Clinical-neurological, ophthalmological, and otoneurological examinations were performed. MRI of the brain was conducted on all patients using high-field scanners (1.5 and 3.0 Tesla), and measurements of the optic nerve (ON) diameter in the intraorbital and intracranial parts, as well as the height and width of the chiasm. Results: The morphometric parameters of the ON diameter in the intraorbital part and the height of the chiasm did not significantly differ between the studied groups (p>0.05). The morphometric parameters of Group I did not differ from the control group (p>0.05). In Group II the average diameter of the intracranial part of the ON (2.31±0.26 mm) and the average width of the chiasm (11.39±0.31 mm) were statistically significantly different from the control group values: 2.97±0.2 mm and 13.69±0.57 mm, respectively, p

This article presents the outcomes of a study that investigates the perceptions among residents of Russia regarding their membership in the Russian nation or society. The study employs interviews (100) and focus groups (40), carried out across five regions of Russia, as its primary data collection methods. The key methodological approach was to pose questions about societal membership and the integration of various migrant types into Russian society, thus revealing underlying beliefs about the criteria for belonging to the Russian nation or society. This approach was especially insightful for understanding perceptions about groups that are typically not questioned about their societal membership. The study identifies two distinct types of societal membership: “organic” and “acquired”. Organic membership is socially ascribed to individuals born in Russia or those with ancestors born in Russia. This category often overlaps with national identity, rendering ethnic Russians born in Russia the quintessential members of Russian society. However, organic membership is not exclusively reserved for ethnic Russians; it extends to other ethnic groups considered part of “the peoples of Russia”, though they are seen as less typical members. Interestingly, the perception of these membership categories varies between regions with distinct national identities and those without such distinctions. Acquired membership, on the other hand, is contingent upon fulfilling specific criteria, such as familiarity with Russian (or regional) culture and a desire to be part of Russian society. Exceptionally, notable achievements can override these criteria. Unlike organic members, individuals with acquired membership can lose their societal status, except in cases of betrayal, which is nearly impossible for organic members. The findings are contextualized within citizenship studies, positing that the described constructs serve as a foundation for the institution of citizenship rather than the converse. Additionally, the study contributes to the ongoing cognitive turn in ethnicity research, offering new insights into the conceptualization of national and societal belonging.

Relevance. One of the main causes of death according to the World Health Organization is cardiovascular diseases. It is well known that dysregulation and/or overexpression of elements of the renin-angiotensin system leads to many negative vascular effects, thereby contributing to the development of cardiovascular diseases and pathological processes, including hypertension, aneurysms, congestive heart failure, stroke, coronary heart disease and endothelial dysfunction.Aim. To consider the main angiotensins and the mechanisms of their action on vascular tone, endothelial functioning, and myocardial function. To demonstrate the participation of the renin-angiotensin system in the formation of the main types of cardiovascular pathology.Results. The lecture discusses the cardiogenic and vascular effects of angiotensins II, 1-7, 1-9 and the role of these angiotensins in the development of atherosclerosis, coronary heart disease, heart failure, and arterial hypertension. The article presents the main principles of correction of the angiotensin system disorder and promising directions of research of this problem.Conclusion. The concept of the classical renin-angiotensin system regulating arterial pressure and vascular tone has evolved into the understanding of this system as a complex network of mediators-anti-tensins and their receptors affecting many physiological pathways.Although the main components of the renin-angiotensin system were discovered more than half a century ago, this system still attracts a large number of researches works in various fields. The renin-angiotensin-aldosterone system has a number of regulatory and counter-regulatory axes that have a significant impact on the course of many diseases. Among the numerous options for cardiovascular therapy used to treat hypertension and heart failure, drugs that affect the renin-angiotensin-aldosterone system play a significant therapeutic role.