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Misinformation, Disinformation, and the Erosion of Institutional Trust: The Role of Social Media in Democracy
No full textIn recent years, social media-driven misinformation and disinformation have helped erode public trust in democratic institutions. This thesis examines how constant exposure to false online content correlates with declining confidence in democracy and evaluates the roles of platforms, influencers, and mechanisms. Using a convergent mixed-methods design, this thesis pairs a quantitative survey with a qualitative analysis of three disinformation case studies: the 2020 U.S. election and the “Stop the Steal” movement, the Rohingya crisis in Myanmar crisis, and Russian denial of wartime atrocities in their invasion against Ukraine. Drawing on classical and modern propaganda theories (Lasswell, Herman & Chomsky, RAND’s Firehose model), the survey found only a weak, non-significant direct correlation between exposure and trust, suggesting that erosion may be indirect and cumulative and mediated by external factors.
However, analysis of the case studies showcase how platforms and influencers on social media amplify the spread of false information, fostering partisan outrage and undermining social cohesion. Survey respondents held both platforms and influencers as equally responsible for spreading misinformation and disinformation, reflecting widespread concerns over their ability to manipulate public opinion and information. Furthermore, survey respondents reported a general pessimism about democracy’s overall future as whole. Together, these findings underscore that pervasive misinformation and disinformation gradually weakens and undermines democratic legitimacy over tim
Assessment of Spatial Autocorrelation and Scalability in Fine-scale Wildfire Random Forest Prediction Models
Get PDFWildfire prediction models that can be applied across diverse regions at fine scales (\u3c 100 m) are critical for wildfire management. Remote sensing offers a path forward by providing heterogeneous and dynamic measurements of fuel load, type, and flammability. Machine learning methods such as random forests provide an empirical framework that are high-accuracy, computationally efficient, interpretable and able to model complex ecological relationships. Here we use high resolution (70 m, every 3–5 days) remote sensing observations of evapotranspiration and evaporative stress index, which represent plant water stress, from Ecosystem Spaceborne Thermal Radiometer on Space Station (ECOSTRESS), as well as topography and weather data, to predict burn severity and occurrence for 8 large wildfires that burned 3715 km2 from 2021 and 2022 in New Mexico, USA. These fires ranged from low to high burn intensity, and covered a diverse range of ecoregions (deserts, grasslands, forests), plant species, and topographies. We used a single model to predict the burn severity of all wildfires one week before occurrence. The prediction accuracy was greatest when using all predictors (ECOSTRESS, weather, topography) (R2 = 0.77). We assessed the role of spatial autocorrelation in driving model performance by: (1) increasing the sample spacing of our dataset, (2) introducing new predictors that represent spatial structure in the data, and (3) training our model on half the fires and predicting the other half of the fires. We found that after increasing sample spacing, model accuracy declined. However, we found declines in model accuracy were more impacted by decreased training set size compared to the distance spacing-indicating that the models are likely accurately capturing fine-scale processes. Scalability of random forest models was also found to be more challenging for regression problems but was accurate for classification of burned pixel occurrence (total pixel accuracy of 67%). These results provide promising results for application of random forest models to predict fine-scale fire severity and occurrence with applications for fire management
Arterial Stiffness in Heart-Healthy Indigenous Tsimane Forager-Horticulturalists
Get PDFBackground Little is known about arterial stiffness in rural subsistence populations that experience few cardiovascular risk factors. We conducted a cross‐sectional study comparing 3 arterial stiffness metrics among Tsimane forager‐horticulturalists with 2 representative US cohorts. Methods Arterial elasticity (the inverse of stiffness) markers C1 (large artery elasticity) and C2 (small artery elasticity) were measured using a tonometry device among 490 Tsimane adults (mean age, 51.2±10.1 years; 55% women), and compared with 6294 multiethnic US adults (mean age, 62.0±10.2 years; 52% women) from MESA (Multi‐Ethnic Study of Atherosclerosis). Carotid‐femoral pulse wave velocity was assessed using the foot‐to‐foot method in a smaller Tsimane sample (n=94) and compared with 3086 predominantly White US adults (mean age, 46.1±8.7 years; 54% women) from the FHS Gen3 (Framingham Heart Study Third Generation). Results Tsimane participants exhibited superior arterial health compared with US cohorts, with higher elasticity (C1/C2) and lower stiffness (carotid‐femoral pulse wave velocity). Their C1 (mean 22.8±12.2 mL/mm Hg×10) and C2 (mean 7.5±4.0 mL/mm Hg×100) were 47.3% and 35.7% higher than MESA participants by age 40 years, respectively, and differences remained sustained throughout adulthood. Compared with participants in FHS Gen3, the carotid‐femoral pulse wave velocity in Tsimane participants (mean 6.2±1.2 m/s) was 33.9% lower and showed a minimal age‐related increase, with carotid‐femoral pulse wave velocity only higher by age 70+ (β=1.74±0.38; reference \u3c 40 years). Tsimane participants with ≥2 comorbidities (hypertension, obesity, and diabetes) had ≈25% higher arterial elasticity than healthy Americans with no comorbidities. Conclusions Tsimane forager‐farmers of the Bolivian Amazon demonstrate substantially lower arterial stiffness throughout adulthood than more urbanized and sedentary populations, and the differences are only partially explained by conventional cardiometabolic risk factors
Childhood Skeletal Lesions Common in Prehistory are Present in Living Forager-Farmers and Predict Adult Markers of Immune Function
Get PDFPorous cranial lesions (cribra cranii and cribra orbitalia) are widely used by archaeologists as skeletal markers of poor child health. However, their use has not been validated with systematic data from contemporary populations, where there has been little evidence of these lesions or their health relevance. Using 375 in vivo computed tomography scans from a cohort-representative sample of adults aged 40+ years from the Bolivian Amazon, among food-limited, high-mortality forager-farmers, we identified cribra cranii on 46 (12.3%) and cribra orbitalia on 23 (6%). Cribra orbitalia was associated with several hallmarks of compromised immune function, including fewer B cells, fewer naïve CD4+ T cells, a lower CD4+/CD8+ T cell ratio, and higher tuberculosis risk. However, neither lesion type predicted other physician-diagnosed respiratory diseases, other markers of cell-mediated immunity, or hemoglobin values. While cribra orbitalia shows promise as a skeletal indicator of health challenges, our findings do not support the continued practice of using these lesions to infer anemia in adults
Pharmacogenetic Exploration of Burenorphine and Related Metabolites in Umbilical Cord Blood
Get PDFThe goal of this study was to explore associations between single-nucleotide polymorphisms (SNPs) and umbilical cord blood concentrations of buprenorphine and its metabolites following maternal administration. This is a sub-study of a prospective observational cohort investigation which included pregnant women receiving buprenorphine for opioid use disorder during pregnancy. Following delivery, umbilical cord blood samples were collected and genotyped using a pharmacogenetic panel. The drug and metabolite concentrations were analyzed through liquid chromatography-mass spectrometry, and genetic association analysis was completed using PLINK software. The included neonates (n = 14) had a mean birth weight of 3.00 ± 0.39 kg and were born to mothers receiving a mean buprenorphine dose of 10.29 ± 6.22 mg. Ten concentration groupings (drug, single metabolite, as well as drug/metabolite(s) combinations) produced 18 unique SNP associations. Two significant associations included variations in CYP3A4 and UGT1A1, which play a role in the metabolism of buprenorphine. These preliminary findings suggest potential pharmacogenetic factors influencing fetal drug exposure, warranting larger studies to validate associations and explore clinical implications for neonatal outcomes
Social Communication Implementable and Applicable Lens: A Framework for Addressing Assessment of Social Communication
Get PDFPurpose: Keegan, Hoepner, et al. (2023) developed a framework for social, cognitive-communication assessment, which was intended to make social communication assessment efficient, comprehensive, and accessible to practicing clinicians. Method: Feedback on the published framework was solicited from expert researchers and clinicians at a variety of conference meetings, including the 2023 International Brain Injury Association Congress, 2023 American Speech-Language-Hearing Association Convention, and 2024 International Cognitive-Communication Disorders Conference. The authors incorporated this feedback to develop an updated, clinically applicable framework of communication entitled Social Communication Implementable and Applicable Lens (SoCIAL). The goal of this update was to provide clinically applicable recommendations that clinicians can feasibly implement in their assessment of social communication. Results: The SoCIAL framework is presented and described with the inclusion of contextual factors. The focus of the framework shifted to the scope of practice of a speech-language pathologist and their role in social communication. Practical, accessible methods and tools that can be applied in the context of this framework are identified and critically appraised. Conclusions: This framework highlights the intersecting variables (contextual, social, personal, and environmental) that clinicians should consider during the assessment process and when working to support collaborative goal setting, as person-centered intervention is planned. While there is a growing literature base that supports a focus on social communication in context, there remains a disconnect between the literature and clinical application that current researchers and practitioners have an opportunity to address. It is our hope that the SoCIAL framework provides a framework for supporting clinical implementation and moving translational research forward
Autism Awareness Training for Law Enforcement Officers: A Pilot Study
Get PDFPurpose
The purpose of this study was to pilot a research-based autism training session for law enforcement officers (LEOs), test the Police Self-Efficacy for Autism (PSEA) scale as a measurement tool for the session and provide a preliminary examination of brief training. Design/methodology/approach
This study utilized a pre-post survey approach in which participants completed the PSEA scale pre- and post-training to measure the relationship between the training and self-efficacy scores. Findings
Results show a positive relationship between brief autism-specific training and officers’ self-efficacy scores across items and subscales. All four subscales and seven of thirteen items demonstrated statistical significance. Originality/value
Though emerging legislation requires officers to document perceived developmental disability in specific interactions (e.g. California Senate Bill 882), officers report limited knowledge regarding characteristics of developmental disabilities such as autism. This pilot effort showed the promise of brief research-based professional learning for officers using pre- and post-training evaluation on the PSEA scale
Advancing Cancer Research via Comparative Oncology
No full textIn the ongoing battle against cancer, the natural world provides promising inspiration for designing novel therapeutic strategies. The field of comparative oncology offers a valuable source of such inspiration. By combining evolutionary biology, ecology, veterinary medicine and clinical oncology, comparative oncology aims to better understand cancer, especially by highlighting taxa that are strongly resistant or susceptible to cancer and to identify the molecular and cellular mechanisms underlying the remarkable cancer resistance of some taxa. Such studies hold profound implications for human cancer research and treatment, and increase the probability of detecting therapeutic avenues that are non-toxic to healthy cells and tissues. This Perspective underscores the importance of comparative oncology, emphasizes its relevance, and showcases recent breakthroughs in identifying natural cancer resistance mechanisms and opportunities for clinical translation. We advocate for a better integration of cancer research on non-conventional model species into oncology and we urge enhanced cooperation between clinicians and comparative oncologists to advance cancer prevention or treatment strategies
Fighting Crime Online: Options, Evidence, and the Empirical Case for Judicial Site Blocking in the U.S.
No full textHere, we discuss the empirical evidence on the effectiveness of various methods of enforcement against criminal behavior on the Internet, synthesizing results from several distinct categories of crime. We then discuss why some methods are more effective than others in reducing illegal activities. We conclude by arguing that judicial website blocking, a method deployed in numerous stable, rights-respecting democracies worldwide, has been shown to have several desirable properties in fighting online criminal activities, and within the bounds of a carefully crafted framework we outline here, could be used safely and effectively in the U.S. as well
Dynamical Regulation of Blood Pressure and Cognitive Function
No full textBACKGROUND
Blood pressure (BP) is not steady. It varies over intervals from months to consecutive cardiac cycles, and this variation contains meaningful information beyond mean BP. Variability over multiple clinic visits (VVV-BP) and during 24-h ambulatory monitoring (ABPV) is positively related to risk of stroke and coronary artery disease and negatively associated with cognitive performance. Beat-to-beat BP variation, often quantified as low frequency variability (0.04–0.15 Hz, LF-BPV), is less well-studied. Here, we examine the relationship between LF-BPV and cognitive outcomes in 1953 participants from the Midlife in the US study. METHODS
Participants completed the Brief Test of Adult Cognition by Telephone from which we derived episodic memory (EMF) and executive function (EFF) factors and a composite index. With participants in the seated position, the continuous BP signal was recorded noninvasively with a Finometer. The resultant time series was submitted to Fourier-based spectral analysis to compute LF-BPV. Linear regression models estimated the associations with cognitive indices. RESULTS
Systolic (LF-SBPV) and diastolic (LF-DBPV) were positively associated with EFF (b = 0.073 ± 0.033, P = 0.02), EMF (b = 0.079 ± 0.036, P = 0.04), and the composite index (b = 0.101 ± 0.035, P = 0.004) after adjustment for age, sex, education, and income. Findings were similar for LF-DBPV. CONCLUSIONS
This positive association is consistent with evidence demonstrating that LF blood pressure variability contributes to increased delivery of oxygenated blood to the brain and clearance of metabolic and cellular waste via the brain’s glymphatic system and intramural periarterial drainage pathway, both of which contribute to superior cognitive performance