Tangent space functional reconfigurations in individuals at risk for alcohol use disorder.

Human brain function dynamically adjusts to ever-changing stimuli from the external environment. Studies characterizing brain functional reconfiguration are nevertheless scarce. Here we present a principled mathematical framework to quantify brain functional reconfiguration when engaging and disengaging from a stop signal task (SST). We apply tangent space projection (a Riemannian geometry mapping technique) to transform functional connectomes (FCs) and quantify functional reconfiguration using the correlation distance of the resulting tangent-FCs. Our goal was to compare functional reconfigurations in individuals at risk for alcohol use disorder (AUD). We hypothesized that functional reconfigurations when transitioning in/from a task would be influenced by family history of alcohol use disorder (FHA) and other AUD risk factors. Multilinear regression model results showed that engaging and disengaging functional reconfiguration were driven by different AUD risk factors. Functional reconfiguration when engaging in the SST was negatively associated with recent drinking. When disengaging from the SST, however, functional reconfiguration was negatively associated with FHA. In both models, several other factors contributed to the explanation of functional reconfiguration. This study demonstrates that tangent-FCs can characterize task-induced functional reconfiguration, and that it is related to AUD risk.

Scanning Electrochemical Microscopy Meets Optical Microscopy: Probing the Local Paths of Charge Transfer Operando in Booster-Microparticles for Flow Batteries.

Understanding the oxidation/reduction dynamics of secondary microparticles formed from agglomerated nanoscale primary particles is crucial for advancing electrochemical energy storage technologies. In this study, the behavior of individual copper hexacyanoferrate (CuHCF) microparticles is explored at both global and local scales combining scanning electrochemical microscopy (SECM), for electrochemical interrogation of a single, but global-scale microparticle, and optical microscopy monitoring to obtain a higher resolution dynamic image of the local electrochemistry within the same particle. Chronoamperometric experiments unveil a multistep oxidation/reduction process with varying dynamics. On the one hand, the global SECM analysis enables quantifying the charge transfer as well as its dynamics at the single microparticle level during the oxidation/reduction cycles by a redox mediator in solution. These conditions allow mimicking the charge storage processes in these particles when they are used as solid boosters in redox flow batteries. On the other hand, optical imaging with sub-particle resolution allows the mapping of local conversion rates and state-of-charge within individual CuHCF particles. These maps reveal that regions of different material loadings exhibit varying charge storage capacities and conversion rates. The findings highlight the significance of porous nanostructures and provide valuable insights for designing more efficient energy storage materials.

Psychometric properties of the Persian version of the nursing moral disengagement scale.

Moral disengagement is a set of cognitive mechanisms through which a person violates his/her moral standards without losing his/her dignity. Therefore, a tool has been designed to measure moral disengagement in nurses. This study aims to determine the psychometric properties of the Nursing Moral Disengagement scale. In this methodological study, 440 nurses working in hospitals of Mashhad were selected by the availability sampling method. The translation was carried out using the forward-backward method. The final version of the tool was psychometrically tested for validity (exploratory and confirmatory factor analysis) and reliability (internal consistency and relative stability). Four factors were extracted in the exploratory factor analysis, and since the factor loadings of all the tool items were higher than 0.3, they were all retained. The tool's general fit indices indicated the model's confirmation and optimal fit. Cronbach's alpha and relative stability coefficients for the whole questionnaire were 0.90 and 0.89, respectively. The study results showed that this tool has good validity and reliability and can therefore measure behaviors related to moral disengagement in nurses, so that appropriate interventions can be designed to reduce these harmful behaviors.

Oxygen Absorption in Electrocatalyst Layers Detected by Scanning Electrochemical Microscopy.

Scanning electrochemical microscopy (SECM) is able to track the local electrochemical activity of an electrolyte-immersed substrate employing an ultra-micro-electrode (UME) in micrometer-scale spatial resolution. In this study, SECM is employed to investigate the presence of oxygen in the electrocatalyst layers of polymer electrolyte membrane fuel cells and electrolyzers. Approach curves on electrocatalyst layers with the tip potential set for oxygen reduction reveal that a significant amount of oxygen is absorbed in the catalyst layer. We confirm that the coexistence of Nafion ionomer and carbon black leads to oxygen confinement. It is suggested that this oxygen is confined within the hydrophobic parts of the self-assembled Nafion on the graphitic surfaces of the carbon black.

Thermodynamics, Charge Transfer and Practical Considerations of Solid Boosters in Redox Flow Batteries.

Solid boosters are an emerging concept for improving the performance and especially the energy storage density of the redox flow batteries, but thermodynamical and practical considerations of these systems are missing, scarce or scattered in the literature. In this paper we will formulate how these systems work from the point of view of thermodynamics. We describe possible pathways for charge transfer, estimate the overpotentials required for these reactions in realistic conditions, and illustrate the range of energy storage densities achievable considering different redox electrolyte concentrations, solid volume fractions and solid charge storage densities. Approximately 80% of charge storage capacity of the solid can be accessed if redox electrolyte and redox solid have matching redox potentials. 100 times higher active areas are required from the solid boosters in the tank to reach overpotentials of <10 mV.

Caloric restriction extends yeast chronological lifespan via a mechanism linking cellular aging to cell cycle regulation, maintenance of a quiescent state, entry into a non-quiescent state and survival in the non-quiescent state.

A yeast culture grown in a nutrient-rich medium initially containing 2% glucose is not limited in calorie supply. When yeast cells cultured in this medium consume glucose, they undergo cell cycle arrest at a checkpoint in late G1 and differentiate into quiescent and non-quiescent cell populations. Studies of such differentiation have provided insights into mechanisms of yeast chronological aging under conditions of excessive calorie intake. Caloric restriction is an aging-delaying dietary intervention. Here, we assessed how caloric restriction influences the differentiation of chronologically aging yeast cultures into quiescent and non-quiescent cells, and how it affects their properties. We found that caloric restriction extends yeast chronological lifespan via a mechanism linking cellular aging to cell cycle regulation, maintenance of quiescence, entry into a non-quiescent state and survival in this state. Our findings suggest that caloric restriction delays yeast chronological aging by causing specific changes in the following: 1) a checkpoint in G1 for cell cycle arrest and entry into a quiescent state; 2) a growth phase in which high-density quiescent cells are committed to become low-density quiescent cells; 3) the differentiation of low-density quiescent cells into low-density non-quiescent cells; and 4) the conversion of high-density quiescent cells into high-density non-quiescent cells.

The concept of hospitalization of children from the view point of parents and children.

OBJECTIVE: Disease and hospitalization can be the first crisis that a child encounters. The aim of this study is to reveal a clear picture of the meaning of hospitalization in children, to show the experience and behavior of hospitalized children and to discover the meaning and understanding of hospitalization in them. METHODS: This study is a phenomenology study of qualitative research within the framework of Husserl Eidetic phenomenology through comprehensive interviewing. The objective group consisted of children 7-11 years old - and their parents - hospitalized in the children's ward of 22 Bahman Hospital and the surgery ward of 15 Khordad Hospital during the study (2008). Method of selection of participants was as follows: having experience of hospitalization, having ability to answer the questions, and being volunteered. Sample size was detected by data saturation. In the method of sampling, an object group of 20 (12 children and 8 parents) were chosen and interviewed. The Seven Colaizzi Stages were used for analysis of data. FINDINGS: The analysis of the interviews and the written narrations of the participants led to the extraction of 6 inner themes consisting of sickness, environment, reciprocal relationship, parents' personal problems, mental and emotional matters and a spiritual dimension; all of which define a specific aspect of the experience of hospital in children and parents. CONCLUSION: The experience of hospitalization in children can be considered as a process of effort for returning to health and, on the whole, the regaining of the individual's status in the world. Nurses can ease this process by showing the importance of experience and feelings of individuals at the time of hospitalization and help people to adapt themselves to their new surroundings. This matter can enable the nurses to utilize methods of helping in the adaptation of individuals and thus guide the unique powers present in every individual to ease and quicken recovery.