Previous research has highlighted the negative impact of the COVID-19 pandemic on healthcare workers’ (HCWs) mental health, yet protective factors remain underexplored. Emerging studies emphasize the importance of trust in government and interpersonal relationships in reducing infections and fostering positive vaccine attitudes. This study investigates the relationship between HCWs’ trust in the workplace and government and depressive symptoms during the pandemic. The COVID-19 HEalth caRe wOrkErS study surveyed 32,410 HCWs from 22 countries, including clinical and nonclinical staff. Participants completed the Patient Health Questionnaire-9 and ad-hoc questions assessing trust in the workplace and government. Logistic regression and multilevel models examined associations between trust levels and depressive symptoms. High workplace trust (OR = 0.72 [0.68, 0.76]) and government trust (OR = 0.72 [0.69, 0.76]) were linked to lower odds of depressive symptoms, with significant between-country variation. Country-level analyses showed that workplace trust was more protective in more developed countries and under stricter COVID-19 restrictions. Despite cross-country variation, HCWs with higher trust in the workplace and government had ~28% lower odds of experiencing depressive symptoms compared to those with lower trust. Promoting trust may help mitigate the mental health impact of future crises on HCWs.

In the field of parafoil airdrop path planning, the inherent complexity and time-sensitive nature of mission requirements necessitate rapid path generation through low-order mathematical models that approximate the system’s true dynamics. This study presents a novel sparse identification framework for constructing a parafoil path planning approximate model. Leveraging high-fidelity 9-degree-of-freedom (9 DOF) dynamic simulation data as training inputs, our method identifies simple nonlinear relationships between 3D positional coordinates (for spatial targeting) and yaw angle (for directional control), which are critical path planning parameters. Compared to conventional 4 DOF models, experimental validation using field airdrop data reveals that the proposed sparse model achieves enhanced predictive accuracy while maintaining computational efficiency. Quantitative analysis demonstrates reductions in root mean square error (RMSE) by approximately 12.96% (horizontal position), 54.44% (height) and 37.96% (yaw angle). The efficacy is further confirmed through successful fixed-point homing across diverse initial deployment scenarios, underscoring its potential for parafoil path planning.

One of the most incredible aspects of the Mexican Baja Peninsula is the immense wealth of plant and animal diversity it holds. The human communities living alongside this richness have boundless intimate knowledge of its natural history, potentially with novel insights into the ecological and evolutionary processes shaping the diversity of plants and animals. These same human communities have likely also witnessed changes to these natural environments over their lifetimes, particularly as the effects of global change are being felt by similar rural communities around the world. However, because the area is so remote, they often have little access to scientific data or current information about the causes or effects of the changes they observe. Using a thematic analysis of recorded conversations, this project seeks to connect remote rural ranches in Mexico with scientists, to gather data on the issues that matter most to the community members, and work to find collaborative solutions. Through thematic analysis of recorded conversations, our research reveals that unpredictable climate variability, including droughts, hurricanes, and shifting seasonal patterns, poses significant challenges to ranching livelihoods. Ranchers’ deep ecological knowledge provides critical insights into the stresses of changing and increasingly unpredictable environmental trends. By integrating local perspectives with scientific approaches, this study highlights the potential for collaborative biodiversity research.

The atomic bombings of Hiroshima and Nagasaki reshaped international politics and the field of International Relations. But one question—“How should the atomic bomb be used?”—has been largely overlooked in political science. This article recovers American deliberations on alternative nuclear use options before August 1945, including the “noncombat demonstration,” targeting military installations, giving advance warning, and striking more symbolically valuable cities. We develop theoretical insights on the value of staging violent spectacles and the emotive power of visible destruction. We then use a wide range of sources to show that U.S. leaders selected an ostentatiously lethal means of atomic debut due to concerns about conventional military inferiority vis-à-vis the Soviet Union, the desire to instill a widespread view of the bomb’s revolutionary character, and the imperative of shaping the postwar international order. This study advances our understanding of the post-1945 international order and the performative dimensions of political violence.

The vast presence of populism in contemporary political discourse has introduced a narrative steeped in nostalgia, evoking images of a revered national past and delineating a stark division between the ‘authentic us’ and the ‘alien them’. While these messages resonate with a substantial portion of citizens, they concurrently foster identity-driven animosity and derogation. In a pre-registered experiment in the Netherlands (with data collected between January and March 2023), we distinguish the influence of nostalgic narratives and scapegoating on societal sentiments, revealing their pivotal role in exacerbating current levels of polarization. Our findings underscore the potential of nostalgic narratives to shape affective sentiments towards ideological and social in-groups, while also influencing sentiments towards out-groups. Messages featuring scapegoats were found to intensify positive sentiment towards in-groups, while simultaneously diminishing positive sentiment towards out-groups. This research underscores a crucial mechanism underpinning the ebb and flow of identity-based sentiments. The results indicate that nostalgic discourse, particularly when intertwined with scapegoating, can serve as a catalyst for the intensification of in-group affinity and the exacerbation of out-group aversion. In essence, our study underscores the far-reaching implications of nostalgic narratives in perpetuating societal animosity and polarization and sheds light on a critical facet of contemporary political discourse.

Gas-phase turbulence in a bubbling gas–solid fluidised bed is modelled using the data from particle-resolved direct numerical simulations. The subgrid particle-induced turbulent kinetic energy (TKE) is modelled as a function of filter width, filtered solid volume fraction, particle Reynolds number and filtered gas-phase strain rate tensor. Within the volume-filtered framework, we demonstrate that the fluid Reynolds stress models originally developed for a homogeneous system remain applicable to the inhomogeneous fluidised bed, provided that the inhomogeneous drag and particle-induced TKE models are used for the dissipation rate interfacial term. An algebraic model for the anisotropy of gas-phase velocity variance is developed by simplifying the proposed Reynolds stress equation model, which incorporates the effects from both filtered slip velocity and filtered fluid strain rate. The new models are shown to agree well with the direct numerical simulation data of clustered particle settling systems, indicating good applicability of our models for various clustered particle-laden flows.

This study compares turbulent channel flows over elastic walls with those over rough walls, to explore the role of the dynamic change of shape of the wall in turbulence. The comparison is made meaningful by generating rough walls from instantaneous configurations of elastic cases. The aim of this comparison is to individually understand the role of fluid–structure interaction effects and the role of wall shape/undulations in determining the overall physics of flow near elastic walls. With an increase in the compliance of the wall, qualitatively similar trends for many of the effects produced by a rough wall are also seen in the elastic wall. However, specific features can be observed for the elastic-wall cases only, arising from the mutual interaction between the solid and fluid, leading to a further increase in drag. To understand them, we look at the turbulent structures, which exhibit clear differences across the various configurations: roughness induces only a slight reduction of streamwise coherency, resulting in a situation qualitatively similar to what is found in classical turbulent channel flows, whereas elasticity causes the emergence of a novel dominant spanwise coherency. Additionally, we explored the effect of vertical disturbances on elastic-wall dynamics by comparing with permeable walls having similar (average) wall-normal velocity fluctuations at the interface. The permeable walls were found to have minimal similarities to elastic walls. Overall, we can state that the wall motion caused by the complex fluid–structure interaction contributes significantly to the flow and must be considered when modelling it. In particular, we highlight the emergence of strong wall-normal fluctuations near the wall, which result in strong ejection events, an attribute not observed for rigid walls.

It is widely believed that high inflation reduces the popularity of incumbents, and contributed to poor incumbent performance in recent elections in the United States and elsewhere. Existing research shows that voters’ inflation perceptions are associated with their evaluations of incumbent parties, but these observational studies cannot eliminate the possibility that the causal relationship runs the other way, where opposition to incumbent governments causes individuals to report higher price increases. To help overcome this inferential challenge, this study draws on a pre-registered experiment embedded in a nationally representative survey fielded just days before the 2024 US Presidential election. We find that priming Americans to think about inflation reduced support for the incumbent party. This effect is most pronounced among Independents and Democrats. These findings suggest that inflation likely contributed to the Democrats’ 2024 electoral defeat, and provide novel evidence that inflation has a causal effect on support for incumbent parties.

The locomotion of microorganisms in complex fluids at low Reynolds numbers has been widely studied by ignoring fluid inertia. Here, we combine the asymptotic analysis and numerical simulations to explore the effect of fluid inertia on the dynamic mechanism of microorganisms swimming through viscoelastic fluids using Taylor’s swimming sheet model, undergoing small-amplitude undulations. Surprisingly, fluid inertia can enhance the speed and efficiency of the infinite-length sheet in viscoelastic fluids at finite Reynolds numbers, in stark contrast to the previous results found in Newtonian fluids. Moreover, speed and efficiency slightly exceed those Newtonian values at the small Weissenberg number due to a passive inertial response of the sheet. We associate this with the magnitude of the hydrodynamic force increasing at finite Reynolds numbers. These insights contribute to a deeper understanding of the inertial effect on the locomotion of microorganisms through complex fluids.

Twin children are more likely to die than singletons. This is an additional burden in sub-Saharan African (SSA) countries, as child mortality levels are already higher than anywhere else. This article provides estimates of under-5 mortality rates (U5MRs) for twins and singletons in SSA from 1986 to 2016. It describes the geographical variations and changes over time. It also describes the variation of twins’ excess mortality according to age from 0 to 5 years. Additionally, it analyzes the factors associated with twins’ excess mortality. We used data from 156 national surveys from 42 countries. We estimated U5MRs for twins and single children and built a Cox model to analyze factors associated with excess mortality among twins. Although child mortality has declined on the continent, twins’ excess mortality remains very high. U5MRs are, on average, 3 times higher among twins than singletons. The Cox model shows that all other things being equal, the adjusted hazard ratio of under-5 mortality (U5M) is 3.2 (2.9−3.3; p < .001) times higher among twins than singletons. The main factors associated with excess mortality risks among twins are biomedical and nutritional features, such as low birth weight, non-use of cesarean section delivery, and lack of breastfeeding. Health policy makers in SSA should be aware of the vulnerability of twins, and interventions to prevent their early deaths should be considered.