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Abstract FeRh-based alloys have attracted significant attention due to their magnetic phase transition and significant magnetocaloric effects. These properties position them as promising candidates for fundamental research and practical applications, including magnetic cooling and targeted drug delivery. The study of FeRh alloys, particularly those where Rhodium or Iron atoms are substituted with other transition metals, is crucial as certain substitutions preserve the alloy’s magnetocaloric properties. However, even within a specific structural type and without considering competing phases, determining which atom (Fe or Rh) is replaced upon introducing a third element remains unclear. This paper addresses this ambiguity through ab initio calculations. We propose an approach to predict whether a dopant will replace Fe or Rh, offering insights into the electronic and structural factors influencing the substitution. Additionally, we present a dataset of ab initio calculations on doped FeRh alloys, which will support future data-driven modeling efforts. Our findings not only advance the understanding of FeRh-based alloys but also contribute to the design of novel materials for experimental and industrial applications.

The results of studying the problem of active sediment formation when mixing residual fuels, caused by manifestation of incompatibility, are presented. A laboratory method has been developed for determining the compatibility and stability of fuels allowing identification of a quantitative characteristic of sediment formation activity. Laboratory studies were performed, and incompatible fuel components were identified. Tests were made to determine the quality indicators of samples and group individual composition of fuels. Results on the content of total and inorganic carbon in the obtained sediments were determined using Shimadzu TOC-V SSM 5000A. Chemical composition was determined and calculated on LECO CHN-628 analyser. Group composition of hydrocarbon fuels contained in the sediment was studied by gas chromato-mass spectrometry on GCMS-QP2010 Ultra Shimadzu. To obtain additional information on the structural group composition of fuel sediment, IR spectrometry was performed on IR-Fourier spectrometer IRAffinity-1. X-ray diffraction analysis of sediment samples was made using X-ray diffractometer XRD-7000 Shimadzu; interplanar distances d002 and d100 as well as Lс and Lа crystallite sizes served as the evaluation criteria. Microstructural analysis of total sediment was performed by scanning electron microscopy. The results of the research confirmed that the content of normal alkanes in the fuel mixture mainly affects sediment formation. Recommendations were drawn on preserving the quality of fuels and reducing sediment formation during storage and transportation.

Among the medical applications of the magnetocaloric effect (MCE) a technology of targeted drug delivery (TDD) is of great interest. The remote, noninvasive drug delivery to human organs or tissues is one of the actual challenges at present. Delivery devices, which provide a controlled, reproducible and reliable drug release, can have a significant impact on the treatment of different diseases. An ideal device for the fast drug delivery should contain a great amount of medication, should not practically release the drug in the off state, be able to repeatedly switch to the on state without mechanical damage, not require the implanted electronics, and be able to release a controlled dose of drug as stated in the physician’s prescription.This paper describes a composite material to coat implants and other drug carriers, which enables to control the quantity and the period of medication release. The paper also offers the results of thermodynamic model’s analysis of these medical devices based on the properties of ‘polymer/magnetic material’ composite systems. The results of magnetic and nonmagnetic nanoparticles deposition on the fragments of abdominal meshes are also presented.

Magnetic oxides are promising materials for alternative health diagnoses and treatments. The aim of this work is to understand the dependence of the heating power with the nanoparticle (NP) mean size, for the manganite composition La0.75Sr0.25MnO3 (LSMO)—the one with maximum critical temperature for the whole La/Sr ratio of the series. We have prepared four different samples, each one annealed at different temperatures, in order to produce different mean NP sizes, ranging from 26 nm up to 106 nm. Magnetization measurements revealed a FC-ZFC irreversibility and from the coercive field as function of temperature we determined the blocking temperature. A phase diagram was delivered as a function of the NP mean size and, based on this, the heating mechanism understood. Small NPs (26 nm) is heated up within the paramagnetic range of temperature (T>Tc), and therefore provide low heating efficiency; while bigger NPs are heated up, from room temperature, within the magnetically blocked range of temperature (TT>TB), for intermediate mean diameter size of 37 nm, with maximum efficiency of heat transfer.

Rare earth metals (REM) occupy a special and important place in our lives. This became especially noticeable during the rapid development of industry in the industrial era of the twentieth century. The tendency of development of the rare-earth metals market certainly remains in the XXI century. According to experts estimates the industry demand for chemical compounds based on them will tend to grow during the nearest years until it reaches the market balance. At the same time, the practical use of high-purity rare-earth metals requires the most accurate understanding of the physical properties of metals, especially magnetic ones. Despite a certain decline in interest in the study of high-purity REM single crystals during the last decade, a number of scientific groups (Ames Lab, Lomonosov Moscow State University (MSU), Baikov Institute of Metallurgy and Materials Science Russian Academy of Science (RAS)) are still conducting high-purity studies on high-purity metal samples. The present article is a combination of a review work covering the analysis of the main works devoted to the study of heavy REMs from gadolinium to thulium, as well as original results obtained at MSU. The paper considers the electronic properties of metals in terms of calculating the density of states, analyzes the regularities of the magnetic phase diagrams of metals, gives the original dependences of the Neel temperature and tricritical temperatures for Gd, Tb, Dy, Er, Ho, Tm, and also introduces a phenomenological parameter that would serve as an indicator of the phase transformation in heavy REMs.

FeRh-based alloys have attracted significant attention due to their magnetic phase transition and significant magnetocaloric effects. These properties position them as promising candidates for fundamental research and practical applications, including magnetic cooling and targeted drug delivery. The study of FeRh alloys, particularly those where Rhodium or Iron atoms are substituted with other transition metals, is crucial as certain substitutions preserve the alloy's magnetocaloric properties. However, even within a specific structural type and without considering competing phases, determining which atom (Fe or Rh) is replaced upon introducing a third element remains unclear. This paper addresses this ambiguity through ab initio calculations. We propose an approach to predict whether a dopant will replace Fe or Rh, offering insights into the electronic and structural factors influencing the substitution. Additionally, we present a dataset of ab initio calculations on doped FeRh alloys, which will support future data-driven modeling efforts. Our findings not only advance the understanding of FeRh-based alloys but also contribute to the design of novel materials for experimental and industrial applications. [ABSTRACT FROM AUTHOR]

It has been indicated that extreme sport activities result in a highly rewarding experience, despite also providing fear, stress and anxiety. Studies have related this experience to the concept of flow, a positive feeling that individuals undergo when they are completely immersed in an activity. However, little is known about the exact nature of these experiences, and, there are still no empirical results to characterize the brain dynamics during extreme sport practice. This work aimed at investigating changes in psychological responses while recording physiological (heart rate-HR, and breathing rate-BR) and neural (electroencephalographic-EEG) data of eight volunteers, during outdoors slackline walking in a mountainous environment at two different altitude conditions (1 m-low-walk- and 45 m-high-walk-from the ground). Low-walk showed a higher score on flow scale, while high-walk displayed a higher score in the negative affect aspects, which together point to some level of flow restriction during high-walk. The order of task performance was shown to be relevant for the physiological and neural variables. The brain behavior during flow, mainly considering attention networks, displayed the stimulus-driven ventral attention network-VAN, regionally prevailing (mainly at the frontal lobe), over the goal-directed dorsal attention network-DAN. Therefore, we suggest an interpretation of flow experiences as an opened attention to more changing details in the surroundings, i.e ., configured as a 'task-constantly-opened-to-subtle-information experience', rather than a 'task-focused experience'., Competing Interests: The authors declare that they have no competing interests., (© 2024 de Sampaio Barros et al.)

Magnetic nanoparticles (MNPs) with various shapes and special (magnetic and thermal) properties are promising for magnetic hyperthermia. The efficiency of this therapy depends mainly on the MNPs' physical characteristics: types, sizes and shapes. This paper presents the hyperthermic temperature values induced by cubic/sphere-shaped MNPs injected within a concentric tissue configuration (malignant and healthy tissues) when an external time-dependent magnetic field was applied. The space-time distribution of the nanoparticles as a result of their injection within a tumoral (benign/malign) tissue was simulated with the bioheat transport equation (Pennes equation). A complex thermo-fluid model that considers the space-time MNP transport and its heating was developed in Comsol Multiphysics. The cubic-shaped MNPs give a larger spatial distribution of the therapeutic temperature in the tumoral volume compared to the spherical-shaped ones. MNP doses that induce the therapeutic (hyperthermic) values of the temperature (40 ÷ 45 °C) in smaller volumes from the tumoral region were analyzed. The size of these regions (covered by the hyperthermic temperature values) was computed for different magnetite cubic/sphere-shaped MNP doses. Lower doses of the cubic-shaped MNPs give the hyperthermic values of the temperature in a larger volume from the tumoral region compared with the spheric-shaped MNPs. The MNP doses were expressed as a ratio between mass concentration and the maximum clinical accepted doses. This thermo-fluid analysis is an important computational instrument that allows the computations of the MNP doses that give therapeutic temperature values within tissues.

The provided dataset represents the performance of adult individuals in three experimental tasks measuring cognitive inhibition: the Stroop task; the SART task and the Eriksen Flanker task. All tasks were initially completed in a web setting (online) by 485 individuals. Additionally, randomly selected participants completed all these tasks one more time (220 participants) or two more times (100 participants) during separate laboratory session(s) offline. The provided dataset contains data both from the offline and online experimental sessions. For the Stroop and Flanker tasks, we have provided data on mean reaction times for correct answers and the percent of correct answers for both congruent and incongruent trials. For the SART task, we have provided data on the number and the percent of commission and omission errors; the mean correct reaction times in "go" trials; the standard deviations of correct reaction times in "go" trials; the coefficients of variability for correct reaction times in "go" trials; the mean reaction times for successful "go" trials proceeding successful "no-go" trials; and the mean reaction times for correct "go" trials proceeding failed "no-go" trials. Data from both laboratory sessions contains information on the age and gender of participants. Additionally, we have provided the dates and hours of all experimental sessions. This dataset can potentially be reused for exploratory research on cognitive inhibition, i.e., the stability of individual cognitive inhibition capacity over time; intercorrelations of various inhibition task performance measures; individual differences in cognitive inhibition; or the influence of task setting (web vs laboratory) on inhibition performance measured in different settings (web vs laboratory)., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Authors.)

In the present paper, we provide a protocol for experimentally measuring and calculating individual inhibitory control capacity index in adult participants in an online Inquisit-based setting. We believe that this method can serve other researchers in the standardized assessment of individual inhibitory control capacity that can be used in studies on the possible role of inhibitory control in many every-day cognitive phenomena. Thus, the paper focuses mainly on the calculation of a composite inhibitory control capacity score from two inhibitory control tasks. Specifically, it is calculated on the basis of participants' performance in two well-established experimental paradigms: the Stroop Task and the Eriksen Flanker Task. The methods described in this protocol have already been successfully applied in both lab and online settings. In the first part of the article, we provide a short theoretical background and a brief description of the previous usage of this method in our two original studies. In the following parts, we provide step-by-step instructions for measuring and calculating the individual inhibitory control capacity index using web-based methodology. The protocol is supplemented with slides of original experimental tasks and instructions for participants (both translated from Polish)., Competing Interests: The authors declare no conflict of interest., (© 2021 The Authors. Published by Elsevier B.V.)

The observation that exerting self-control in an initial task impairs subsequent self-control performance in a following task has been used to explain a wide range of phenomena. If evidence for this "ego-depletion" effect was initially believed to be strong, it is now questioned. Recent meta-analyses indicated that this effect was sensitive to publication bias and that it was greatly reduced after control for this bias. In a pre-registered replication attempt where an ego-depletion protocol was conducted in multiple independent laboratories, the effect was not distinguishable from zero. Here, a different approach is adopted to examine the validity of this effect by improving the experimental protocol with the addition of important methodological precautions: 1) a pre-test measurement, 2) a learning period, 3) a prolonged depleting task, 4) a similar control condition, and 5) valid indexes of self-control. Accordingly, a well-learned Simon task was done before and after 1h of continuous practice of a Stroop task in a high inhibition demands condition (75% of incongruent trials) or in a control condition (0% of incongruent trials). Datasets from between-subjects (Study 1, N = 82) and within-subjects (Study 2, N = 52) experiments were analyzed using generalized linear mixed models. A significant ego-depletion effect was found in Study 1 (greater interference effect and accuracy decline in high inhibition demands than in control condition) but not in Study 2. Because it is difficult to explain this difference in results, the findings suggest that, even in a context chosen to optimize the observation of an ego-depletion effect, it seems difficult to be conclusive about the existence of this effect., Competing Interests: The authors have declared that no competing interests exist.

Background: Physical activity programs (PAP) in patients with cardiovascular disease require evidence of cost-utility. To assess improvement in health-related quality of life (QoL) and reduction of health care consumption of patients following PAP, a randomized trial was used., Methods: Patients from a health insurance company who had experienced coronary artery disease or moderate heart failure were invited to participate (N = 1891). Positive responders (N = 50) were randomly assigned to a progressively autonomous physical activity (PAPA) program or to a standard supervised physical activity (SPA) program. The SPA group had two supervised sessions per week over 5 months. PAPA group had one session per week and support to aid habit formation (written tips, exercise program, phone call). To measure health-related quality of life EQ-5D utility score were used, before intervention, 6 months (T6) and 1 year later. Health care costs were provided from reimbursement databases., Results: Mobility, usual activities and discomfort improved significantly in both group (T6). One year later, EQ-5D utility score was improved in the PAPA group only. Total health care consumption in the intervention group decreased, from a mean of 4097 euros per year before intervention to 2877 euros per year after (p = 0.05), compared to a health care consumption of 4087 euros and 4180 euros per year, in the total population of patients (N = 1891) from the health insurance company. The incremental cost effectiveness ratio was 10,928 euros per QALYs., Conclusion: A physical activity program is cost-effective in providing a better quality of life and reducing health care consumption in cardiovascular patients., Trial Registration: ISRCTN77313697 , retrospectively registered on 20 November 2015.

In a recent study, the differential effects of prolonged physiologically challenging exercise upon two executive processes (cognitive control and working memory) were investigated. However, the impact of exercise on the selective inhibition task employed was debatable and needed further analysis to dissociate the effects induced by exercise intensity from those induced by the time spent on task upon cognitive control outcomes. In this study, we propose a thorough analysis of these data, using a generalized mixed model on a trial-by-trial basis and a new measure of the strength of the automatic response based on reaction time distribution, to disentangle the effect of physical fatigue from cognitive fatigue. Despite the prolonged duration of exercise, no decline in cognitive performance was found in response to physical fatigue. The only change observed during 60-min exercise was an acceleration of the correct trials and an increase of errors for incompatible trials. This pattern, shown during low and physiologically challenging exercise, supports the occurrence of cognitive fatigue induced by the repetition of the cognitive tasks over time.

Background: The benefits of supervised physical activity programs in cardiac rehabilitation have been amply demonstrated, but the quantity of physical activity often declines quickly once supervision ends. This trial assesses the effectiveness of an experimental intervention drawing on habit formation theory to maintain physical activity., Methods: Cardiovascular patients (N = 47) were randomly assigned to one of two groups. The first group participated in two supervised physical activity (SPA) sessions per week for 20 weeks. The second group was offered a progressively autonomous physical activity (PAPA) program as follows: the same supervised program as the SPA group for 10 weeks and then a further 10 weeks with one supervised session replaced by a strategy to build and sustain the habit of autonomous physical activity. The International Physical Activity Questionnaire (IPAQ; Craig et al. Med Sci Sports Exerc 35(8):1381-1395, 2003) was used to measure the quantity of physical activity, which was the primary outcome. The number of participants was limited, and we thus took multiple IPAQ measurements (at 0, 5, 7, 9 and 12 months after the start of the intervention) and used a mixed model for analysis. Physical condition, automaticity of the physical activity behavior, motivation, and quality of life were examined for changes., Results: No significant between-group differences were noted for physical activity behaviors after the program, physical condition, motivation, or behavioral automaticity. The PAPA group nevertheless completed more PA sessions during the intervention, and their quality of life was significantly higher than that of the SPA group at 12 months., Conclusion: Although the number of supervised sessions was lower, the progressively autonomous PA program resulted in the same or even higher positive outcomes than the fully supervised PA program., Trial Registration: Current Controlled Trials ISRCTN77313697 , retrospectively registered on 20 November 2015.

Background: Although the benefits of supervised physical activity programs in cardiac rehabilitation have been well documented, the amount of physical activity often drops quickly after the end of the supervised period. This trial (registered as ISRCTN77313697 ) will evaluate the effectiveness of an experimental intervention based on habit formation theory applied to physical activity maintenance., Methods/design: Cardiovascular patients (N = 56) will be individually randomized into two groups. Two supervised physical activity (SPA) sessions per week will be offered to the first group for 20 weeks. Progressively autonomous physical activity (PAPA) will be offered to the second group as follows: 10 weeks of the same supervised program as the SPA group followed by 10 more weeks in which one supervised session will be replaced by a strategy to build and sustain the habit of autonomous practice of physical activity. The primary outcome is the amount of physical activity measured by the International Physical Activity Questionnaire (IPAQ; Craig et al., Med Sci Sport Exercises 35(8):1381-95, 2003). To compensate for the limited capacity to recruit subjects, multiple IPAQ measurements will be made (at T0, T5, T7, T9 and T12 months after the start of the intervention) and analyzed using the mixed model approach. We will also assess changes in physical and physiological indicators, automaticity of the physical activity behavior, motivation and quality of life. Last, we will assess the cost-effectiveness for each type of program., Discussion: If proven to be effective, the PAPA intervention, which requires fewer supervised sessions, should provide a cost-effective solution to the problem of physical activity maintenance in cardiac rehabilitation.