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Flexible behavior requires gating mechanisms that encode only task-relevant information in working memory. Extant literature supports a theoretical division of labor whereby lateral frontoparietal interactions underlie information maintenance and the striatum enacts the gate. Here, we reveal neocortical gating mechanisms in intracranial EEG patients by identifying rapid, within-trial changes in regional and inter-regional activities that predict subsequent behavioral outputs. Results first demonstrate information accumulation mechanisms that extend prior fMRI (i.e., regional high-frequency activity) and EEG evidence (inter-regional theta synchrony) of distributed neocortical networks in working memory. Second, results demonstrate that rapid changes in theta synchrony, reflected in changing patterns of default mode network connectivity, support filtering. Graph theoretical analyses further linked filtering in task-relevant information and filtering out irrelevant information to dorsal and ventral attention networks, respectively. Results establish a rapid neocortical theta network mechanism for flexible information encoding, a role previously attributed to the striatum.

How do we think about time? Converging lesion and neuroimaging evidence indicates that orbitofrontal cortex (OFC) supports the encoding and retrieval of temporal context in long-term memory1, which may contribute to confabulation in individuals with OFC damage2. Here, we reveal that OFC damage diminishes working memory for temporal order, that is, the ability to disentangle the relative recency of events as they unfold. OFC lesions reduced working memory for temporal order but not spatial position, and individual deficits were commensurate with lesion size. Comparable effects were absent in patients with lesions restricted to lateral prefrontal cortex (PFC). Based on these findings, we propose that OFC supports understanding of the order of events. Well-documented behavioral changes in individuals with OFC damage2 may relate to impaired temporal-order understanding.

How do we rapidly process incoming streams of information in working memory, a cognitive mechanism central to human behavior? Dominant views of working memory focus on the prefrontal cortex (PFC), but human hippocampal recordings provide a neurophysiological signature distinct from the PFC. Are these regions independent, or do they interact in the service of working memory? We addressed this core issue in behavior by recording directly from frontotemporal sites in humans performing a visuospatial working memory task that operationalizes the types of identity and spatiotemporal information we encounter every day. Theta band oscillations drove bidirectional interactions between the PFC and medial temporal lobe (MTL; including the hippocampus). MTL theta oscillations directed the PFC preferentially during the processing of spatiotemporal information, while PFC theta oscillations directed the MTL for all types of information being processed in working memory. These findings reveal an MTL theta mechanism for processing space and time and a domain-general PFC theta mechanism, providing evidence that rapid, dynamic MTL-PFC interactions underlie working memory for everyday experiences.

How does the human brain rapidly process incoming information in working memory? In growing divergence from a single-region focus on the prefrontal cortex (PFC), recent work argues for emphasis on how distributed neural networks are rapidly coordinated in support of this central neurocognitive function. Previously, we showed that working memory for everyday "what," "where," and "when" associations depends on multiplexed oscillatory systems, in which signals of different frequencies simultaneously link the PFC to parieto-occipital and medial temporal regions, pointing to a complex web of sub-second, bidirectional interactions. Here, we used direct brain recordings to delineate the frontoparietal oscillatory correlates of working memory with high spatiotemporal precision. Seven intracranial patients with electrodes simultaneously localized to prefrontal and parietal cortices performed a visuospatial working memory task that operationalizes the types of identity and spatiotemporal information we encounter every day. First, task-induced oscillations in the same delta-theta (2-7 Hz) and alpha-beta (9-24 Hz) frequency ranges previously identified using scalp electroencephalography (EEG) carried information about the contents of working memory. Second, maintenance was linked to directional connectivity from the parietal cortex to the PFC. However, presentation of the test prompt to cue identity, spatial, or temporal information changed delta-theta coordination from a unidirectional, parietal-led system to a bidirectional, frontoparietal system. Third, the processing of spatiotemporal information was more bidirectional in the delta-theta range than was the processing of identity information, where alpha-beta connectivity did not exhibit sensitivity to the contents of working memory. These findings implicate a bidirectional delta-theta mechanism for frontoparietal control over the contents of working memory.

The purpose of this study is to investigate whether all students, regardless of racial and socioeconomic status, have equal access to the Green Ribbon Schools. Recent research on the benefits of green schools and green school programs have demonstrated positive effects correlated with green spaces, particularly with enhanced attention, improved academic performance, fostered outdoor education, and overall well-being. The Green Ribbon award is a recognition award that honors schools that are environmentally conscious and have a focus on sustainability. Any school may apply for this award through their state. If a state nominates more than two schools or districts, at least one of the schools must serve at least 40 percent of students from disadvantageous backgrounds. This specific aims of this study is to find out whether the majority of awarded public Green Ribbon Schools are equally distributed among disadvantaged students. The list of ED Green Ribbon public schools for the years 2013 through 2015 was collected from the Green Ribbon School website through the Department of Education. Racial/ethnic and socioeconomic data was collected from the Elementary/Secondary Information System, which is a database created by the National Center for Education Statistics. The data was then analyzed to determine racial and socioeconomic distribution. The study found that the majority of awarded public Green Ribbon Schools did not serve at least 40 percent disadvantaged students. The majority of Green Ribbon Schools (61%) are primarily attended by White students. Just under 50% of Green Ribbon Schools serve at least 40% socioeconomically disadvantaged students. The chi-squared test found that race/ethnicity and socioeconomic status of the students were not equally distributed for the Green Ribbon Schools (= 30.60, p< 0.0005). This determined that race and socioeconomic status are related factors, and it is not just due to chance that the majority of Green Ribbon Schools are White

BackgroundQuiescence, reversible exit from the cell division cycle, is characterized by large-scale changes in steady-state gene expression, yet mechanisms controlling these changes are in need of further elucidation. In order to characterize the effects of post-transcriptional control on the quiescent transcriptome in human fibroblasts, we determined mRNA decay rates for over 10,000 genes using a transcription shut-off time-course.ResultsWe found that ~500 of the genes monitored exhibited significant changes in decay rate upon quiescence induction. Genes involved in RNA processing and ribosome biogenesis were destabilized with quiescence, while genes involved in the developmental process were stabilized with quiescence. Moreover, extracellular matrix genes demonstrated an upregulation of gene expression that corresponded with a stabilization of these transcripts. Additionally, targets of a quiescence-associated microRNA (miR-29) were significantly enriched in the fraction of transcripts that were stabilized during quiescence.ConclusionCoordinated stability changes in clusters of genes with important functions in fibroblast quiescence maintenance are highly correlated with quiescence gene expression patterns. Analysis of miR-29 target decay rates suggests that microRNA-induced changes in RNA stability are important contributors to the quiescence gene expression program in fibroblasts. The identification of multiple stability-related gene clusters suggests that other posttranscriptional regulators of transcript stability may contribute to the coordination of quiescence gene expression. Such regulators may ultimately prove to be valuable targets for therapeutics that target proliferative cells, for instance, in cancer or fibrosis.

Working memory (WM) is the ability to hold information for online processing. As the basis of long-term memory formation and a fundamental construct of thinking, it is paramount that we understand how WM works. Distributed network models posit that the prefrontal cortex (PFC) supports WM by coordinating top-down control over other regions involved in sensory representation and long-term memory. We utilized an episodic memory paradigm that probes WM for identity, spatial, and temporal information to examine the PFC dependent model of WM. In two studies, multimodal electrophysiology data reveal that PFC control over WM is fundamentally dynamic in nature, and that WM is dependent on activity distributed across anterior and posterior cortical regions. Results challenge the simple PFC model of WM.Ch. 1 presents evidence from intracranial recordings that frontal and medial temporal lobe (MTL) theta rhythms carry WM-related activity, and uncovers two WM systems. The PFC-MTL system exhibits bidirectional interaction that shifts with msec precision in response to task demands. In contrast, MTL rhythms direct activity in the orbitofrontal cortex via theta rhythms that do not vary with task demands. These findings support a bidirectional PFC-MTL system in humans – in which theta rhythms subserve executive control during episodic memory formation. Ch. 2 presents evidence from patients with unilateral PFC damage, which shows that a posteriorly-sourced alpha-beta network provides adequate resources for well above-chance WM accuracy. However, when the PFC is intact, PFC low theta activity increases commensurate with executive demand, and PFC-sourced slow rhythms and posteriorly-sourced alpha-beta rhythms travel in opposite directions to support optimal WM.Ch. 3 reviews 15 years of intracranial research on human memory, and considers the potential of intracranial electrophysiology as a technique to address unresolved questions in the neuroscience of human memory. Ch. 4 presents key

Formin family actin nucleators are potential coordinators of the actin and microtubule cytoskeletons, as they can both nucleate actin filaments and bind microtubules in vitro. To gain a more detailed mechanistic understanding of formin-microtubule interactions and formin-mediated actin-microtubule cross-talk, we studied microtubule binding by Cappuccino (Capu), a formin involved in regulating actin and microtubule organization during Drosophila oogenesis. We found that two distinct domains within Capu, FH2 and tail, work together to promote high-affinity microtubule binding. The tail domain appears to bind microtubules through nonspecific charge-based interactions. In contrast, distinct residues within the FH2 domain are important for microtubule binding. We also report the first visualization of a formin polymerizing actin filaments in the presence of microtubules. Interestingly, microtubules are potent inhibitors of the actin nucleation activity of Capu but appear to have little effect on Capu once it is bound to the barbed end of an elongating filament. Because Capu does not simultaneously bind microtubules and assemble actin filaments in vitro, its actin assembly and microtubule binding activities likely require spatial and/or temporal regulation within the Drosophila oocyte.

Coordination of actin and microtubule cytoskeletal networks is required for a number of fundamental cellular processes. Formin family actin nucleators are emerging coordinators of the actin and microtubule cytoskeletons, as they can both nucleate actin filaments and bind microtubules in vitro. To gain a more detailed mechanistic understanding of formin-microtubule interactions and formin-mediated actin-microtubule crosstalk, we studied microtubule binding by Cappuccino (Capu), a formin involved in regulating actin and microtubule organization during Drosophila oogenesis. We report that two distinct domains within Capu, FH2 and tail, work together to promote high-affinity microtubule binding. Microtubules potently inhibit Capu's actin nucleation activity but have little effect on Capu once bound to the barbed end of an elongating actin filament, supporting a model in which Capu does not simultaneously bind microtubules and assemble actin in vivo. After characterizing Capu-microtubule binding in vitro, we examined the localization of Capu and microtubules in S2 cells. We did not observe any obvious colocalization and conclude that S2 cells are not an ideal system for visualizing in vivo formin-microtubule interactions. To better understand Capu's mechanisms of action during oogenesis, we then systematically characterized several classical capu alleles. While all of these capu mutants exhibit severe developmental defects, they variably affect Capu's actin assembly activity in vitro. Together with our microtubule binding data, this indicates that Capu's physiological role extends beyond its ability to nucleate actin filaments. We therefore performed tandem affinity purification experiments to identify novel Capu binding partners and gain additional insight into Capu's role during oogenesis. We report several candidate binding partners involved in such diverse cellular processes as mitochondrial fission, endocytosis, and nuclear import. Though preliminary, these results

The capacity to keep multiple items in short-term memory (STM) improves over childhood and provides the foundation for the development of multiple cognitive abilities. The goal of this study was to measure the extent to which age differences in STM capacity are related to differences in task engagement during encoding. Children (n = 69, mean age = 10.6 years) and adults (n = 54, mean age = 27.5 years) performed two STM tasks: the forward digit span test from the Wechsler Intelligence Scale for Children (WISC) and a novel eyetracking digit span task designed to overload STM capacity. Building on prior research showing that task-evoked pupil dilation can be used as a real-time index of task engagement, we measured changes in pupil dilation while participants encoded long sequences of digits for subsequent recall. As expected, adults outperformed children on both STM tasks. We found similar patterns of pupil dilation while children and adults listened to the first six digits on our STM overload task, after which the adults' pupils continued to dilate and the children's began to constrict, suggesting that the children had reached their cognitive limits and that they had begun to disengage from the task. Indeed, the point at which pupil dilation peaked at encoding was a significant predictor of WISC forward span, and this relationship held even after partialing out recall performance on the STM overload task. These findings indicate that sustained task engagement at encoding is an important component of the development of STM.

Systematic infrared and nuclear magnetic resonance investigations of common crustal minerals were undertaken to better understand the geologic significance of minor components of structural hydrous species within these nominally anhydrous minerals. The absolute hydrogen concentration in three alkali feldspars and eight plagioclase samples was measured with ¹H nuclear magnetic resonance spectroscopy. The mid-infrared integral absorption coefficient was determined to be 15.3 ± 0.7 ppm⁻¹cm⁻², allowing quantitative analysis of OH and H₂O in feldspars with infrared spectroscopy. A survey of hydrous species in igneous feldspars found that feldspars contain structural OH (0-512 ppm H₂O), H₂O (0-1350 ppm H₂O), and NH₄⁺ (0-1500 ppm NH₄⁺) groups as well as fluid inclusions and alteration products. Composition and crystal structure influence the type of hydrous species that can be incorporated into feldspars, but the concentration and speciation of structural hydrogen is at least partially determined by the geologic environment. The diffusivity of H in OH-bearing plagioclase was determined at 800-1000°C (D0=5.7±2.5x10⁻⁴ m²/sec and Q=224±33 kJ/mol). A millimeter-sized volcanic feldspar phenocryst would be expected to lose a significant proportion of its OH concentration on the timescale of a typical eruption (hours to weeks). The structures and compositions of low albite and ussingite, Na₂AlSi₃O₈(OH), are similar. The strong hydrogen bonding in ussingite is found to be fundamentally different from the hydrogen bonding environment of OH in feldspars. Comparison of the infrared spectra of structural isomorphs reedmergnerite, NaBSi₃O₈, and low albite suggest that OH is incorporated in both structures through protonation of the most underbonded oxygen site. The concentration of structural OH in diopside was determined for four granulite facies siliceous marble samples from the Adirondacks, New York. Diopside OH concentration increases monotonically with incr

IN PROCESSING Professor of Modern Languages at Winthrop College from 1922-1955, Dr. Johnson discusses her background, honors in school, how the Great Depression affected Winthrop, teaching at Winthrop, American Association of University Women (AAUW) involvement, "adoption" of foster children, travel in Europe, the Rock Hill Planning Commission and other teaching positions after retirement.

The UMKC University Libraries held the second Rainbow Read-In (RRI) virtually in June 2022. Readers presented either their own works if they identify as LGBTQIA+ or works written by LGBTQIA+ authors. Nine participants presented and sixty people attended. Our first Rainbow Read-In included ten presenters and forty attendees in 2021. The goal of this presentation is to share how we created a safe space to showcase works from within the queer community. The objectives of this program are to discuss the origins of the RRI, the formation of the committee, lessons learned, short- and long-term goals, potential areas for improvement, and examples of the range of queer voices represented. New events usually take time to become established, but our event had a head start. UMKC University Libraries hosted the first African American Read-In (AARI) in 2009. As the co-chair of the AARI committee for six years and the creator of the RRI, this presentation will address how the AARI served as a foundation and inspiration for creating a safe and supportive environment for building community for the RRI. We created the transformative program that we wanted to attend. The initial success of this innovative event proves that, as a bunch of library nerds, if you build it, they will come.

The UMKC University Libraries held the second Rainbow Read-In (RRI) virtually in June 2022. Readers presented either their own works if they identify as LGBTQIA+ or works written by LGBTQIA+ authors. Nine participants presented and sixty people attended. Our first Rainbow Read-In included ten presenters and forty attendees in 2021. The goal of this presentation is to share how we created a safe space to showcase works from within the queer community. The objectives of this program are to discuss the origins of the RRI, the formation of the committee, lessons learned, short- and long-term goals, potential areas for improvement, and examples of the range of queer voices represented. New events usually take time to become established, but our event had a head start. UMKC University Libraries hosted the first African American Read-In (AARI) in 2009. As the co-chair of the AARI committee for six years and the creator of the RRI, this presentation will address how the AARI served as a foundation and inspiration for creating a safe and supportive environment for building community for the RRI. We created the transformative program that we wanted to attend. The initial success of this innovative event proves that, as a bunch of library nerds, if you build it, they will come.