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Working memory function changes across development and varies across individuals. The patterns of behavior and brain function that track individual differences in working memory during human development, however, are not well understood. Here, we establish associations between working memory, other cognitive abilities, and functional MRI (fMRI) activation in data from over 11,500 9- to 10-year-old children (both sexes) enrolled in the Adolescent Brain Cognitive Development (ABCD) Study, an ongoing longitudinal study in the United States. Behavioral analyses reveal robust relationships between working memory, short-term memory, language skills, and fluid intelligence. Analyses relating out-of-scanner working memory performance to memory-related fMRI activation in an emotional n-back task demonstrate that frontoparietal activity during a working memory challenge indexes working memory performance. This relationship is domain specific, such that fMRI activation related to emotion processing during the emotional u-back task, inhibitory control during a stop-signal task (SST), and reward processing during a monetary incentive delay (MID) task does not track memory abilities. Together, these results inform our understanding of individual differences in working memory in childhood and lay the groundwork for characterizing the ways in which they change across adolescence. [ABSTRACT FROM AUTHOR]

In financial markets, the weak form of the efficient market hypothesis implies that price returns are serially uncorrelated sequences. In other words, prices should follow a random walk behavior. Recent developments in evolutionary economic theory (Lo, 2004) have tailored the concept of adaptive market hypothesis (AMH) by proposing that market efficiency is not an all-or-none concept, but rather market efficiency is a characteristic that varies continuously over time and across markets. Within the AMH framework, this work considers the Dow Jones Index Average (DJIA) for studying the deviations from the random walk behavior over time. It is found that the market efficiency also varies over different time scales, from weeks to years. The well-known detrended fluctuation analysis was used for the characterization of the serial correlations of the return sequences. The results from the empirical showed that interday and intraday returns are more serially correlated than overnight returns. Also, some insights in the presence of business cycles (e.g., Juglar and Kuznets) are provided in terms of time variations of the scaling exponent. [ABSTRACT FROM AUTHOR]

In the first year of the COVID-19 pandemic, U.S. undocumented immigrants were at heightened risk of contracting COVID-19, with many of them being "frontline essential workers" and residing in crowded living spaces. Given undocumented immigrants' elevated susceptibility to contracting COVID-19 at the peak of uncertainty surrounding the virus, we used the structural influence model of communication to explore: (1) how undocumented immigrants acquired information about COVID-19; (2) how they assessed information trustworthiness and accuracy; (3) their perceptions of COVID-19; and (4) how they prevented or managed COVID-19. Drawing from semi-structured interviews with 46 Latina/o/x/e undocumented immigrants residing in California, we found four key themes: (1) (dis)trust in traditional media as participants relied heavily on social media for COVID-19 information; (2) weak and strong ties played a crucial role in co-constructing health outcomes with different levels of organization; (3) learning about COVID-19 through (in)direct experiences; and (4) coping through health literacy and cultural beliefs. The study's findings can inform future efforts to reach highly-vulnerable immigrant communities during a crisis (or different outbreaks in COVID-19 variants), and hopefully, help reduce health inequities.