The past few years were marked by increased online offensive strategies perpetrated by state and non-state actors to promote their political agenda, sow discord, and question the legitimacy of democratic institutions in the US and Western Europe. In 2016, the US congress identified a list of Russian state-sponsored Twitter accounts that were used to try to divide voters on a wide range of issues. Previous research used latent Dirichlet allocation (LDA) to estimate latent topics in data extracted from these accounts. However, LDA has characteristics that may limit the effectiveness of its use on data from social media: The number of latent topics must be specified by the user, interpretability of the topics can be difficult to achieve, and it does not model short-term temporal dynamics. In the current paper, we propose a new method to estimate latent topics in texts from social media termed Dynamic Exploratory Graph Analysis (DynEGA). In a Monte Carlo simulation, we compared the ability of DynEGA and LDA to estimate the number of simulated latent topics. The results show that DynEGA is substantially more accurate than several different LDA algorithms when estimating the number of simulated topics. In an applied example, we performed DynEGA on a large dataset with Twitter posts from state-sponsored right- and left-wing trolls during the 2016 US presidential election. DynEGA revealed topics that were pertinent to several consequential events in the election cycle, demonstrating the coordinated effort of trolls capitalizing on current events in the USA. This example demonstrates the potential power of our approach for revealing temporally relevant information from qualitative text data.

Globally, the grey-headed albatross Thalassarche chrysostoma is listed as Endangered due to decreasing populations at its major breeding colonies. We analysed the population trend at Marion Island using annual counts of incubating pairs and fledglings from 1984 to 2021 and three methods: TRends and Indices for Monitoring data (TRIM), a generalized additive model and a state-space model. In contrast to rapid decreases at most other colonies, all three methods indicated a local population increase at an average annual rate of 1.3%. The latter two models indicated a decreasing trend from 1997 to 2002, presumably related to mortality on longlines set for Patagonian toothfish Dissostichus eleginoides around the island, which peaked from 1996 to 1998. Grey-headed albatrosses exhibit greater variation in annual counts than other seabird species at Marion Island, possibly linked to interannual variation in breeding success because they are biennial breeders. However, breeding success alone was not significant in any of the models, presumably because it cannot capture the complexities of both population processes and environmental variation. Although all three models predicted the overall trends well, integrated population models, which can account for demographic processes, might be more appropriate to model long-term population trends.

Similar to adults with posttraumatic stress disorder, children with early life adversity show bias in memory for negative emotional stimuli. However, it is not well understood how childhood adversity impacts mechanisms underlying emotional memory. N = 56 children (8–14 years, 48% female) reported on adverse experiences including potentially traumatic events and underwent fMRI while attending to emotionally pleasant, neutral, or negative images. Post-scan, participants completed a cued recall test to assess memory for these images. Emotional difference-in-memory (DM) scores were computed by subtracting negative or positive from neutral recall performance. All children showed enhancing effects of emotion on recall, with no effect of trauma load. However, children with less trauma showed a larger emotional DM for both positive and negative stimuli when amygdala or anterior hippocampal activity was higher. In contrast, highly trauma-exposed children demonstrated a lower emotional DM with greater amygdala or hippocampal activity. This suggested that alternative neural mechanisms might support emotional enhancement of encoding in children with greater trauma load. Whole-brain analyses revealed that right fusiform activity during encoding positively correlated with both trauma load and successful later recall of positive images. Therefore, highly trauma-exposed children may use alternative, potentially adaptive neural pathways via the ventral visual stream to encode positive emotional events.

The COVID-19 pandemic has presented youth and families with a broad spectrum of unique stressors. Given that adolescents are at increased risk for mental health and emotional difficulties, it is critical to explore family processes that confer resilience for youth in the face of stress. The current study investigated caregiver emotion regulation (ER) as a familial factor contributing to youth ER and risk for psychopathology following stressful life events. In a longitudinal sample of 224 youth (Mage = 12.65 years) and their caregivers, we examined whether caregiver and youth engagement in ER strategies early in the pandemic mediated the associations of pandemic-related stress with youth internalizing and externalizing symptoms six months later. Leveraging serial mediation analysis, we demonstrated that caregiver and youth rumination, but not expressive suppression or cognitive reappraisal, mediated the prospective associations of pandemic-related stress with youth internalizing and externalizing symptoms. Greater exposure to pandemic-related stressors was associated with greater caregiver rumination, which, in turn, related to greater rumination in youth, and higher levels of youth internalizing and externalizing symptoms thereafter. Family interventions that target caregiver ER, specifically rumination, may buffer against the consequences of stress on youth engagement in maladaptive ER strategies and risk for psychopathology.

OBJECTIVES/GOALS: The Community Research Liaison Model (CRLM) is a novel model to facilitate community engaged research (CEnR) and community–academic research partnerships focused on health priorities identified by the community. We describe the CRLM development process and how it is operationalized today. METHODS/STUDY POPULATION: The CRLM, informed by the Principles of Community Engagement, builds trust among rural communities and expands capacity for community and investigator-initiated research. We followed a multi-phase process to design and implement a community engagement model that could be replicated. The resulting CRLM moves community–academic research collaborations from objectives to outputs using a conceptual framework that specifies our guiding principles, objectives, and actions to facilitate the objectives (i.e., capacity, motivations, and partners), and outputs. RESULTS/ANTICIPATED RESULTS: The CRLM has been fully implemented across Oregon. Six Community Research Liaisons collectively support 18 predominantly rural Oregon counties. Since 2017, the liaison team has engaged with communities on nearly 300 community projects. The CRLM has been successful in facilitating CEnR and community–academic research partnerships. The model has always existed on a dynamic foundation and continues to be responsive to the lessons learned by the community and researchers. The model is expanding across Oregon as an equitable approach to addressing health disparities across the state. DISCUSSION/SIGNIFICANCE: Our CRLM is based on the idea that community partnerships build research capacity at the community level and are the backbone for pursuing equitable solutions and better health for communities we serve. Our model is unique in its use of CRLs to facilitate community–academic partnerships; this model has brought successes and challenges over the years.

This study was undertaken to investigate the changes in flocculation properties of Fe-rich smectite (nontronite, NAu-1) suspensions, including settling velocity, aggregate size and floc architecture associated with microbial Fe(III)-reduction in the smectite structure. The dissimilatory Fe-reducing bacterium Shewanella oneidensis MR-1 was incubated with lactate as the electron donor and structural Fe(III) as the sole electron acceptor for 3, 12, 24 and 48 h in an anaerobic chamber. Two controls were prepared; the first was identical to the experimental treatments except that heat-killed cells were used (non-reduced control), and the second control was the same as the first except that the incubation was carried out in an aerobic environment. The extent of Fe(III) reduction for the 48 h incubation was observed to reach up to 18%. Neither the non-reduced control nor the aerobically inoculated sample showed Fe(III) reduction. Compared with the non-reduced control, there was a 2.7 μm increase in mean aggregate size and a 30-fold increase in average settling velocity in the bioreduced smectite suspensions as measured using a Micromeritics Sedigraph®. The aerobically inoculated smectite showed a similar aggregate-size distribution to that of the non-reduced control. Significant changes in physical properties of smectite suspensions induced by microbial Fe(III) reduction were measured directly using transmission electron microscopy. The floc architecture of bioreduced smectite revealed less open structures compared to those of a non-reduced control. The aspect ratio (thickness/length) of individual smectite particle increased from 0.11 for the non-reduced control to 0.18 on average for the bioreduced smectite suspensions. The effects of pH on the clay flocculation were minimal in this study because the value of pH remained nearly constant at pH = 7.0–7.3 before and after the experiments. We therefore suggest that the increase in net negative charge caused by microbial Fe(III) reduction significantly promoted clay flocculation by increasing the electrochemical attraction in the smectite suspensions.

Microstructural changes induced by the microbial reduction of Fe(III) in nontronite by Shewanella oneidensis were studied using environmental cell (EC)-transmission electron microscopy (TEM), conventional TEM, and X-ray powder diffraction (XRD). Direct observations of clays by EC-TEM in their hydrated state allowed for the first time an accurate and unambiguous TEM measurement of basal layer spacings and the contraction of layer spacing caused by microbial effects, most likely those of Fe(III) reduction. Non-reduced and Fe(III)-reduced nontronite, observed by EC-TEM, exhibited fringes with mean d001 spacings of 1.50 nm (standard deviation, σ = 0.08 nm) and 1.26 nm (σ = 0.10 nm), respectively. In comparison, the same samples embedded with Nanoplast resin, sectioned by microtome, and observed using conventional TEM, displayed layer spacings of 1.0–1.1 nm (non-reduced) and 1.0 nm (reduced). The results from Nanoplast-embedded samples are typical of conventional TEM studies, which have measured nearly identical layer spacings regardless of Fe oxidation state. Following Fe(III) reduction, both EC- and conventional TEM showed an increase in the order of nontronite selected area electron diffraction patterns while the images exhibited fewer wavy fringes and fewer layer terminations. An increase in stacking order in reduced nontronite was also suggested by XRD measurements. In particular, the ratio of the valley to peak intensity (v/p) of the 1.7 nm basal 001 peak of ethylene glycolated nontronite was measured at 0.65 (non-reduced) and 0.85 (microbially reduced).

People living with HIV experience psychosocial needs that often are not addressed. We designed an innovative low-resource model of phone-based psychosocial counseling (P-PSC). We describe cohort characteristics, acceptability, feasibility and utilization of P-PSC at health facilities supported by Baylor Foundation Malawi. Staff were virtually oriented at 120 sites concurrently. From facility-based phones, people with new HIV diagnosis, high viral load, treatment interruption or mental health concerns were referred without identifiable personal information to 13 psychosocial counselors via a WhatsApp group. Routine program data were retrospectively analyzed using univariate approaches and regressions with interrupted time series analyses. Clients utilizing P-PSC were 63% female, 25% youth (10–24 y) and 9% children (<10 y). They were referred from all 120 supported health facilities. Main referral reasons included new HIV diagnosis (32%), ART adherence support (32%) and treatment interruption (21%). Counseling was completed for 99% of referrals. Counseling sessions per month per psychosocial counselor increased from 77 before P-PSC to 216 in month 1 (95% CI = 82, 350, p = 0.003). Total encounters increased significantly to 31,642 in year 1 from ~6,000 during the 12 prior months, an over fivefold increase. P-PSC implementation at 120 remote facilities was acceptable and feasible with immediate, increased utilization despite few psychosocial counselors in Malawi.

The Community Research Liaison Model (CRLM) is a novel model to facilitate community-engaged research (CEnR) and community–academic research partnerships focused on health priorities identified by the community. This model, informed by the Principles of Community Engagement, builds trust among rural communities and expands capacity for community and investigator-initiated research. We describe the CRLM development process and how it is operationalized today. We followed a multi-phase process to design and implement a community engagement model that could be replicated. The resulting CRLM moves community–academic research collaborations from objectives to outputs using a conceptual framework that specifies our guiding principles, objectives, and actions to facilitate the objectives (i.e., capacity, motivations, and partners), and outputs. The CRLM has been fully implemented across Oregon. Six Community Research Liaisons collectively support 18 predominantly rural Oregon counties. Since 2017, the liaison team has engaged with communities on nearly 300 community projects. The CRLM has been successful in facilitating CEnR and community–academic research partnerships. The model has always existed on a dynamic foundation and continues to be responsive to the lessons learned by the community and researchers. The model is expanding across Oregon as an equitable approach to addressing health disparities across the state.

Early life adversity (ELA) has been linked with increased arousal responses to threat, including increased amygdala reactivity. Effects of ELA on brain function are well recognized, and emerging evidence suggests that caregivers may influence how environmental stressors impact children’s brain function. We investigated the hypothesis that positive interaction between mother and child can buffer against ELA effects on children’s neural responses to threat, and related symptoms. N = 53 mother–child pairs (children ages 8–14 years) were recruited from an urban population at high risk for violence exposure. Maternal caregiving was measured using the Parenting Questionnaire and in a cooperation challenge task. Children viewed fearful and neutral face stimuli during functional magnetic resonance imaging. Children who experienced greater violence at home showed amygdala sensitization, whereas children experiencing more school and community violence showed amygdala habituation. Sensitization was in turn linked with externalizing symptoms. However, maternal warmth was associated with a normalization of amygdala sensitization in children, and fewer externalizing behaviors prospectively up to 1 year later. Findings suggested that the effects of violence exposure on threat-related neural circuitry depend on trauma context (inside or outside the home) and that primary caregivers can increase resilience.