Texas A&M University

This study evaluated the effects of passive back-support exoskeletons (BSEs) on biomechanical load and postural stability during simulated manual timber felling at three cutting heights. Twenty healthy adult male participants performed timber felling tasks under four BSE conditions (two rigid, one soft, and no BSE). During the tasks, electromyographic (EMG) activity, trunk angle, postural sway, and perceived exertion were measured. Results showed that rigid BSEs reduced trunk flexion and low back EMG activity at the middle cutting height, where trunk flexion was greatest. No significant changes were observed at low or high cutting heights, likely due to insufficient exoskeleton engagement. BSE use shifted postural control strategies rather than providing a uniform stabilizing effect. Additionally, BSEs lowered perceived exertion for the whole body and low back. These findings suggest that BSEs may help reduce low back loading at the middle cutting height during manual timber felling, but further field testing is warranted.

Green hydrogen, an emerging energy carrier that may help achieve national and global decarbonization goals, will reshape energy geographies. States are partnering with firms, offering subsidies and other incentives for developing hubs as agglomerations of green hydrogen producers, off-takers, and exporters, while new and incumbent firms are seeking new accumulation opportunities through the production of green hydrogen. Legitimation processes are key to the implementation and dissemination of new technological systems, but they are not well understood in the context of emerging green hydrogen hubs. We analyze the content of legitimization discourses supporting a green hydrogen hub in Ceará state, northeastern Brazil, seeking to determine the emerging space-making processes. We focus on the cognitive dimension of legitimacy through analysis of ∼ 500 news articles published between 2020 and 2023 in two major media outlets reporting on the proposed green hydrogen hub. The findings describe cognitive legitimation discourses on territorial characteristics, global leadership, breaking from the past, urgency, and essential state action. Legitimation mobilized ideas about landscape, territory, place, scale, and development through normative and technical arguments. Application of the cognitive dimension of legitimation advances economic geographies by highlighting how sub-national organizations represent their territories as adding value for investors, how stakeholders mobilize ideas for de-risking new technologies by overstating benefits and obscuring possible risks to producing states, and how elites justify processes leading to new spatial configurations of low-carbon energy systems. • Elite stakeholders legitimize green hydrogen through diverse arguments. • The cognitive dimension of legitimacy revealed space-making claims. • Legitimation deploys new scalar relationships and imaginations of landscape and territory.

• We exploit quasi-random differences in regional media access in West Germany. • There is credible evidence for a positive effect of TV on the well-being of adults. • Rich survey data from various sources reveal the behavioral responses to TV access. • Negative correlations between TV and well-being are likely driven by self-selection. • We discuss a variety of relevant implications from the perspective of public policy. While watching television is one of the most time-consuming human activities, its potential negative effects on well-being are discussed in the literature as a prime example of irrational behavior. We are the first to comprehensively address this possible paradox by exploiting a novel setting in the research on the effects of television for society: a natural experiment in the late 1980s where people in a few geographically restricted areas of West Germany received commercial TV via terrestrial frequencies. Rich panel data combined with precisely calculated frequency signals allow us to determine how regional availability of commercial TV affects time-use, before investigating the implications for individual well-being over time. Contrary to previous research, we find no evidence of negative health impacts when TV consumption increases. For life satisfaction, we even find a positive effect, which is robust across various sensitivity analyses and subgroups of TV viewers. By also considering evidence from expenditure data and from our own separately conducted surveys, we discuss the external validity of our findings as well as possible mechanisms and conclude that correlational evidence on the well-being effects of TV viewing could be driven by negative self-selection.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remains a significant global health threat because of its rapid evolution and high mutation rate, which limits the performance of existing molecular diagnostics. This study presents a dual-mode, aptamer-based detection platform that combines high sensitivity with mutation resilience. Using a computer-assisted X-aptamer Systematic Evolution of Ligands by EXponential enrichment (SELEX) approach, we identified NP14, a high-affinity, dual-target DNA aptamer that specifically binds to the SARS-CoV-2 nucleocapsid (N) protein at its N-terminal domain. Analyses via molecular docking, aptamer truncation, and targeted mutagenesis revealed that NP14 interacted with both SARS-CoV-2 and SARS-CoV N proteins and identified key nucleotides C24 and G27 of the P1 region and structural determinants critical for its high-affinity binding. Building on this discovery, we engineered a dual-mode biosensing system by integrating NP14 into a multicolor dynamic light scattering-enhanced enzyme-linked aptamer-antibody assay (MD ELAAA). MD ELAAA synergistically combines two complementary detection strategies: i) non-aggregative plasmonic colorimetry for visual signal detection and ii) dynamic light scattering for ultrasensitive quantitative analysis, in which Au/Ag nanomaterials are used to amplify optical and scattering signals. This system achieves a sensitivity of 0.43 TCID50/mL, representing a 47-fold improvement over standard methods. By integrating high sensitivity, specificity, variant recognition, and dual-mode signal output, the MD ELAAA platform enables reliable detection of low-abundance SARS-CoV-2 antigens. Its robust performance supports early-stage diagnostics and high-throughput variant monitoring, establishing MD ELAAA as a robust platform for next-generation viral detection and surveillance.