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Feed algorithms are widely suspected to influence political attitudes. However, previous evidence from switching off the algorithm on Meta platforms found no political effects1. Here we present results from a 2023 field experiment on Elon Musk's platform X shedding light on this puzzle. We assigned active US-based users randomly to either an algorithmic or a chronological feed for 7 weeks, measuring political attitudes and online behaviour. Switching from a chronological to an algorithmic feed increased engagement and shifted political opinion towards more conservative positions, particularly regarding policy priorities, perceptions of criminal investigations into Donald Trump and views on the war in Ukraine. In contrast, switching from the algorithmic to the chronological feed had no comparable effects. Neither switching the algorithm on nor switching it off significantly affected affective polarization or self-reported partisanship. To investigate the mechanism, we analysed users' feed content and behaviour. We found that the algorithm promotes conservative content and demotes posts by traditional media. Exposure to algorithmic content leads users to follow conservative political activist accounts, which they continue to follow even after switching off the algorithm, helping explain the asymmetry in effects. These results suggest that initial exposure to X's algorithm has persistent effects on users' current political attitudes and account-following behaviour, even in the absence of a detectable effect on partisanship.

The aim of the study was to clarify how ethnic identity may impact poor mental health outcomes related to discrimination among Arab American adults in Southeast Michigan, USA. 286 respondents completed a health attitudes and behaviors survey. We used structural equation modeling with path and multi-group analyses to examine moderation effects of ethnic identity on the relationship between discrimination and depression and anxiety, and further moderation based on gender. Ethnic identity positively buffered against depression and anxiety associated with discrimination. In the subgroup analysis, ethnic identity was protective for female participants, though not male participants. These findings provide evidence for ethnic identity as a buffer between discrimination and poor mental health among Arab American adults. Mechanisms may include feelings of belonging and social support. The stronger effects for women may be due to their role of transmitting cultural and religious traditions. Future interventions should incorporate ethnic identity as a protective feature for mental health.

In the digital economy, social media has become a critical channel through which corporate executives communicate with investors, thereby influencing market expectations and price dynamics. This study examines how CEO social media behavior affects stock price volatility from an information-theoretic perspective combined with deep learning methods. Using Lei Jun (Xiaomi) and Elon Musk (Tesla) as contrasting cases, we analyze executive communication under transactional and transformational leadership styles. Emotional tone, thematic alignment, and diffusion intensity are extracted using BERT and LDA, and incorporated into a Long Short-Term Memory (LSTM) model to forecast short-term stock price movements. To interpret the mechanism behind the predictive results, we introduce a novel metric: Semantic Resonance Dissipation Entropy (SRE). Derived from Kullback-Leibler divergence, this indicator measures the informational friction between executive semantic output and market attention. The empirical analysis shows that incorporating these high-dimensional semantic features significantly improves volatility prediction. Moreover, leadership style is closely associated with distinct entropic regimes: Transactional leadership corresponds to relatively stable semantic patterns and low entropy, whereas transformational leadership is associated with higher entropy and greater semantic dispersion. Following Musk's acquisition of Twitter, the previously unstable information environment evolved into a persistent structural factor priced by the market. These findings suggest that the economic impact of digital leadership depends on limiting information dissipation to ensure signal clarity in financial markets.

Evidence linking household air pollution exposure and blood hemoglobin concentration is lacking. We examine the effect of a liquefied petroleum gas cookstove and fuel intervention on hemoglobin concentration, along with associations between household air pollution exposures and hemoglobin concentration, among pregnant women. We enroll 800 pregnant women each in Guatemala, Peru, India, and Rwanda in an open-label randomized controlled trial (NCT02944682). In 3178 women (intervention=1585; control=1593), we measure hemoglobin concentration and 24-hour personal exposure to particulate matter with an aerodynamic diameter ≤2.5μm (PM2.5), black carbon (BC), and carbon monoxide (CO) at three timepoints (9-20, 24-28, and 32-36 weeks gestation). We evaluate the effects of the intervention on hemoglobin concentration and conduct exposure-response analyses to examine associations between 24-hour personal exposure to measured pollutants and hemoglobin concentration. We identify a significant increase in hemoglobin in the intervention group (0.074 g/dL, 95% CI: 0.002, 0.145) compared to the control group. In exposure-response analyses, each 1ppm increase in CO exposure is associated with a 0.015 g/dL (95% CI: 0.008, 0.023) increase in hemoglobin. In our analyses, neither PM2.5 nor BC are associated with hemoglobin concentration. Further research may be needed to examine the biological mechanisms underlying our findings.

The aim was to describe employers' perceptions of what nursing programs do well to prepare students for competent practice as new graduate nurses (NGNs) and areas for improvement. There is a gap in knowledge regarding educators' and employers' expectations and evaluation of competence in NGNs. A qualitative descriptive study of nurse orientation leaders and nurse preceptors was conducted. Major themes were as follows: We Expect Them to Know the Basics, Nursing Schools Do a Pretty Good Job, and Teach Them to Understand the Nurse's Role. Four subthemes included the following: Expose Students to the Reality of Nursing, Focus on Communication Skills, Teach Students to See the Big Picture, and Strategies for Practice Readiness. Nurse educators can help students to integrate knowledge and experience in ways that mimic the actual practice of nursing, thus producing graduates who are better prepared to enter today's complex health care arena.

Rational decision-making often depends on coordinating sequences of mental actions, each with a distinctive phenomenology. Feelings of effort and fluency are central to many theoretical accounts of cognitive control. In the present study (N = 308), we examined how different mental actions-focusing, inhibiting, deciding, visualizing, visualizing alternatives, seeing, believing, and remembering-and their associated phenomenology relate to one another and to varying levels of control. Self-reported mental effort was positively associated with self-reported mental control, with this relationship stronger under higher than lower cognitive-load conditions. Effort was also positively related to control across all eight mental actions, with no clear division between more passive and more active forms. By contrast, the way effort and control combined to produce feelings of successful performance depended on the type of mental action, reflecting a passive-active distinction. This suggests that control and effort have a nuanced relationship to each other and with eliciting targeted mental actions.

Background: The intestinal mucus layer is comprised of heavily glycosylated mucins, including mucin 2 (MUC2), that serve as a nutrient source for certain bacterial members of the gut microbiota. Only a subset of gut commensals encode the glycoside hydrolases required to degrade mucin glycans. However, mucin-degrading microbes can release glycans and generate compounds that can cross-fed non-mucin degrading microbes, creating complex microbial networks. While pairwise studies have shown that mucin degradation drives cross-feeding and metabolite exchange, the broader impact of mucins on community structure and metabolic output remains poorly understood. Objective: In this study, we sought to identify how a defined microbial consortium of human commensals with varied mucin-degrading capacities responds to MUC2 to shape community composition and metabolic output. Methods: A defined consortium of human gut commensals with varied mucin-degrading capacities was cultivated in anaerobic bioreactors in the presence or absence of porcine MUC2. Community composition was assessed, and extracellular metabolites were quantified using targeted and untargeted metabolomic profiling. Results: MUC2 supplementation significantly altered community structure, promoting the expansion of Akkermansia muciniphila while reducing Prevotella. MUC2 also reshaped microbial metabolism, decreasing acetate levels while increasing propionate, butyrate, and formate. In addition, MUC2 supplementation altered amino acid utilization and vitamin metabolism and reduced several neuroactive compounds, including glutamate, γ-aminobutyric acid (GABA), and anthranilic acid, while increasing tryptamine levels. Conclusion: These findings demonstrate that mucins exert broad effects on microbial community structure and metabolic output. Collectively, this work highlights the central role of bacterial cross-feeding in shaping gut ecosystem function.

[This corrects the article DOI: 10.3389/fpubh.2026.1799483.].

The current study examined suicide and violent crime data for 100 large municipalities in the United States. Suicide occurred more often when high school graduation rates were lower, but paradoxically, better income inequality rates predicted higher suicide, though this is consistent with international economic data. The frequency of mental distress predicted suicide as expected. Communities with higher proportions of black residents were more resilient to suicide, and why this is may be worth exploring in future research.

Ashwagandha (Withania somnifera L.Dunal) is an adaptogenic herb known to reduce stress and enhance well-being in adults. This randomized, double-blind, placebo controlled, parallel-group trial evaluated the efficacy and safety of standardized Ashwagandha root extract (ARE) in children with parent-reported concerns related to attention, concentration, or memory. Eight-five healthy children aged 6-12 years were randomized to receive ARE gummies (n = 42; 150 mg twice daily) or identical placebo gummies (n = 43) for 8 weeks. Primary outcomes included attention, memory, and executive function assessed using the Computerized Mental Performance Assessment System (COMPASS). Secondary outcomes included overall functioning and well-being assessed using the Strengths and Difficulties Questionnaire (SDQ), Behavior Rating Inventory of Executive Function, Second Edition (BRIEF2 Parent version), Sleep Disturbance Scale for Children (SDSC), and Patient-Reported Outcomes Measurement Information System - Fatigue Scale. Safety was evaluated based on self-reported adverse events. Among 73 participants who completed the study (ARE, n = 39; placebo, n = 34), ARE supplementation significantly improved speed of information processing (p = 0.040). Improvements were also observed in delayed word recall (p = 0.038, d = 0.59), Stroop task accuracy (p = 0.021, d = 0.61), Corsi block span (p = 0.013, d = 0.66), and choice reaction time accuracy (p = 0.005, d = 0.75). Additionally, SDSC scores improved, indicating better parent-reported sleep quality (p = 0.035). No significant adverse events were reported. These findings suggest that an eight-week supplementation with ARE is well tolerated and may enhance cognitive performance and sleep quality in children. The trial was prospectively registered with the Clinical Trials Registry of India (CTRI/2021/10/037126; dated 06/10/2021; CTRI) and the Australian and New Zealand Clinical Trials Registry (Reg. No.: ACTRN12621000656831; ANZCTR-Registration).

Clinical trials have produced inconclusive results regarding the optimal glucose range for a patient with sepsis in the intensive care unit (ICU) receiving insulin treatment. To investigate the optimal glucose range in patients with sepsis in the ICU independent of confounding covariates. Targeted trial emulation of glucose ranges using causal inference targeted maximum likelihood estimation and longitudinal mixed-effects models combined with survival models. Single-centre, academic referral hospital in Boston, Massachusetts, USA. Adults fulfilling sepsis 3 criteria with at least three glucose readings and insulin treatment from the Medical Information Mart for Intensive Care (MIMIC)-IV database (2008-2019). Five predefined glucose distributions with means at 100, 130, 160 (baseline), 190 and 220&#x2009;mg/dL mimicking current guidelines' recommendations (140-180&#x2009;mg/dL). The primary outcome was in-hospital mortality. Modified counterfactual treatment-policy risks across distinct time-weighted glucose ranges were estimated. Of 73&#x2009;181 eligible patients, 8002 patients with a median age of 66 years (41%&#x2009;women, 67% white ethnicity, 57% diabetes) were included. There was a U-shaped curve between glucose range and mortality in patients without diabetes, but overall, this association was not significant (mean glucose at 100&#x2009;mg/dL with 21% mortality and mean glucose at 220&#x2009;mg/dL with 26% mortality, p-for-trend 0.26). Mortality was lowest at 17%, with mean glucose between 130 and 160&#x2009;mg/dL. Hypoglycaemic events (<80&#x2009;mg/dL) became increasingly more frequent with tighter glucose control 16% at 220&#x2009;mg/dL compared with 77% at 100&#x2009;mg/dL (p-for-trend 0.01). Joint modelling corroborated these results and did not identify covariates that would favour lower glucose ranges in subsets of patients. Our data suggest a U-shaped association of glucose and mortality with an optimal average glucose between 160 and 190&#x2009;mg/dL. These results confirm current guideline recommendations. Together with recent results from randomised controlled trials, intensivists should aim for a liberal glucose range in most patients.

Stark disparities in the outcome of myocardial infarction (MI) persist, with large unexplained variations affecting younger Black women. Mental stress-induced myocardial ischemia (MSIMI) is an emerging mechanistic pathway that may help explain excess risks in this group. We sought to determine whether MSIMI is more common in Black women with recent premature MI than other demographic groups. We cross-sectionally studied 602 individuals 61&#x2009;years and younger who were hospitalized for MI in the previous 8&#x2009;months. Participants underwent 99mTc-sestamibi myocardial perfusion imaging at rest and after mental stress (speech task). A summed difference score was used to quantify ischemia. Clinically significant MSIMI was defined as a summed difference score &#x2265;3. Log-binomial and robust Poisson regression were used to adjust for sociodemographic, lifestyle, clinical, and psychosocial factors. The mean age of patients was 51&#x2009;years (range, 25-61&#x2009;years), 46% were women, and 59% self-identified as Black. Black women had a more adverse psychosocial profile and higher rates of obesity and diabetes but a less severe index MI. The incidence of MSIMI was approximately doubled in Black women than the other groups (P<0.001 for interaction). Clinical and psychosocial risk factors did not explain these differences. In a fully adjusted model, the risk ratio of MSIMI for Black women was 2.2 (95% CI, 2.0-2.5) compared with Black men, 2.3 (95% CI, 1.8-2.9) compared with non-Black women, and 1.8 (95% CI, 1.4-2.2) compared with non-Black men. Among midlife individuals with a recent MI, Black women have a disproportionately higher risk of MSIMI. Targeted interventions for this high-risk group are needed.