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There is growing concern about the impact of declining political trust on democracies. Psychological research has introduced the concept of epistemic (mis)trust as a stable disposition acquired through development, which may influence our sociopolitical engagement. Given trust’s prominence in current politics, we examined the relationship between epistemic trust and people’s choices of (un)trustworthy political leaders. In two representative samples in the UK and US (N = 1096), we tested whether epistemic trust predicts political leader choices through three political dimensions: dogmatism, political trust, and ideology. Although epistemic trust did not directly predict choices of political leaders, it predicted dogmatism and political ideology, which in turn predicted choices of political leaders. A network analysis revealed that epistemic trust and political dimensions only interact through their common connection with dogmatism. These findings suggest that cognitive and affective development may underlie an individual’s political ideology and associated beliefs.
Aircraft ground taxiing contributes significantly to carbon emissions and engine wear. The electric towing tractor (ETT) addresses these issues by towing the aircraft to the runway end, thereby minimising ground taxiing. As the complexity of ETT towing operations increases, both the towing distance and time increase significantly, and the original method for estimating the number of ETTs is no longer applicable. Due to the substantial acquisition cost of ETT and the need to reduce waste while ensuring operational efficiency, this paper introduces for the first time an ETT quantity estimation model that combines simulation and vehicle scheduling models. The simulation model simulates the impact of ETT on apron operations, taxiing on taxiways and takeoffs and landings on runways. Key timing points for ETT usage by each aircraft are identified through simulation, forming the basis for determining the minimum number of vehicles required for airport operations using a hard-time window vehicle scheduling model. To ensure the validity of the model, simulation model verification is conducted. Furthermore, the study explores the influence of vehicle speed and airport scale on the required number of ETTs. The results demonstrate the effective representation of real-airport operations by the simulation model. ETT speed, airport runway and taxiway configurations, takeoff and landing frequencies and imbalances during peak periods all impact the required quantity of ETTs. A comprehensive approach considering these factors is necessary to determine the optimal number of ETTs.
Consider the flow through a channel with grooved edges on one (or both) side(s). If heating is applied to the boundaries, thermal drift is the flow generated by the interaction of the groove and heating patterns. It is known that, if one side of a channel is smooth while the other is grooved, the application of heating forms a so-called ‘thermal drift engine’. Two thermal drift engines are activated if both surfaces are grooved, and these may reinforce or oppose each other. Carefully choosing these engines can lead to an intensification of the thermal drift. The interplay of two drift engines is explored using a horizontal slot with grooves that have a sinusoidal profile with a prescribed wavenumber $\alpha $. It is shown that the strength of the flow decreases proportional to $\alpha $ as $\alpha \to 0$ and proportional to ${\alpha ^{ - 1}}$ as $\alpha \to \infty $. We determine the value of $\alpha $ corresponding to the strongest flow and characterize how the conclusions should be modified if a uniform heating component is added to the heating pattern.
Every complex organization is sometimes marked by preference heterogeneity, disagreement, and conflict. Within political parties, such frictions are traditionally viewed negatively, while recent research has started to perceive them more positively. How might such contradictory evaluations be explained? Through a three-step conceptual analysis we (1) identify two analytical perspectives on intraparty friction, one rooted in a primarily structural conception of parties, one in a primarily behavioral conception; and (2) specify a minimal definition of intraparty friction, which underpins a hierarchical concept structure to (3) suggest a way to resolve contradictions in the consequences attributed to intraparty frictions. Structuralist accounts often view frictions as negative due to a more demanding conceptual threshold, suggesting different types and levels of risk taking by conflict partners. Conversely, behavioralist perspectives see friction more often as beneficial because they focus on expressed disagreement without necessitating an organizational response. Our conceptual tools have important implications for research on membership organizations generally.
This review aimed to identify health impacts of climate change on persons with disabilities in developing countries as well as factors influencing the vulnerability and resilience of affected individuals to related natural disasters.
Methods
PubMed, PsycINFO, Scopus, and Embase databases were searched, 2005 to 2023 inclusive, focusing on the keyword terms “persons with disabilities”, “climate change” and “developing countries”. Identified articles were screened for inclusion and qualifying articles received a full-text review. Of 463 articles identified, following removal of six duplicates, 457 articles were screened; 412 were excluded. Of the remaining 45 full-text articles assessed for eligibility, 15 were selected and included in the review with two additional articles from a manual search.
Results
Findings revealed themes including the impact of climate change on the physical and mental health of persons with disabilities in developing countries. The general theme of resilience to natural disasters and specific coping strategies were also elaborated.
Conclusions
While there is increasing recognition of the psychosocial impacts of climate change-related natural disasters on persons with disabilities, there remain significant gaps in awareness of mental health needs and related service provision. Resolving these gaps is indispensable to achieving equitable climate change-related health outcomes in developing countries.
What challenges do researchers encounter in authentically engaging with the field site and academia when certain aspects of their true identities diverge from the established norms within those domains? Using the case of female political scientists who conduct research on gender politics in the Middle East and North Africa, I highlight the ethical, logistical, and epistemological challenges of carrying out research in a politically and socially closed context. Few studies have investigated how the research process and the knowledge it produces are affected by the intertwinement of authoritarianism and patriarchy, and by the researcher’s positionality within this context. This study fills this gap by drawing upon interviews with feminist political scientists who were born and raised in the region but are based in Western academic institutions to examine the impact of authoritarianism, patriarchy, and the researchers’ insider/outsider positionality on the research process. The analysis shows three key findings. First, researching gender politics is a contentious topic that places researchers on the radar of the state. For scholars who are originally from the region, the issue is compounded by the fact that they are sometimes viewed as traitors by the regime in their country of origin, which accuses them of tarnishing the image of the government and scrutinizing its gender policies. Second, within the wider society, the politics of representation also impose certain limitations and expectations on female scholars. Such limitations include gendered restrictions on their access and mobility in the field. Finally, feminist researchers share how the knowledge they produce, which centers social justice demands, is not always valued in the discipline of political science. The article contributes to this discipline by expanding our understanding of the interplay between identity politics, fieldwork practices, and knowledge production in complex political and social settings.
Congress directed the Secretary of Defense (DoD) to conduct a Pilot program to increase the National Disaster Medical System’s (NDMS) surge capacity, capabilities, and interoperability to support patient movement during a large-scale overseas contingency operation.
Methods
The Pilot conducted a mixed methods exploratory study, the Military-Civilian NDMS Interoperability Study (MCNIS), identifying 55 areas of solutions for NDMS innovation that align with interagency stakeholder interests. Priorities were determined via facilitated discussions, refined and validated by all five Pilot sites.
Results
As the DoD provides essential support for the patient movement component within NDMS, the results highlighted areas for improvement between receiving patients at an airfield and moving them to NDMS definitive care partners during a large medical surge event. This includes patient tracking capabilities, transportation processes and patient placement.
Conclusions
In collaboration with the Departments of Health & Human Services, Homeland Security, Transportation, and Veterans Health Administration, the Pilot is addressing these areas for improvement, by executing site-specific projects that will be validated and identified for export across the system. Leaders across the Pilot site healthcare networks are working to enhance patient movement and tracking. Ultimately, the Pilot will deliver dozens of proven solutions to enhance the NDMS’s patient movement capabilities.
The measurement of lift on symmetrically shaped obstacles immersed in low Reynolds number flow is the quintessential way to signal odd viscosity. For flow past cylinders, such a lift force does not arise if incompressibility and no-slip boundary conditions are fulfilled, whereas for spheres, a lift force has been found in Stokes flow, which is valid for cases where the Reynolds numbers are negligible and convection can be ignored. When considering the role of convection at low but non-zero Reynolds numbers, two hurdles arise, the Whitehead paradox and the breaking of axial symmetry, which are overcome by the method of matched asymptotic expansions and the Lorentz reciprocal theorem, respectively. We also consider the case where axial symmetry is preserved because the translation of the sphere is aligned with the axis of chirality of odd viscosity. We find that while lift vanishes, the interplay between odd viscosity and convection gives rise to a stream-induced torque.
Artificial intelligence (AI) in emergency medicine has been increasingly studied over the past decade. However, the implementation of AI requires significant buy-in from end-users. This study explored desired clinical applications of AI by emergency physicians.
Methods
A 3-round Delphi process was undertaken using STAT59 software. An international expert panel was assembled through purposeful sampling to reflect a diversity in geography, age, time in practice, practice setting, role, and expertise. Items generated in Round 1 were collated by the study team and ranked in Rounds 2 and 3 on a 7-point linear numeric scale of importance. Consensus was defined as a standard deviation of 1.0 or less.
Results
Of 66 invited experts, 29 completed Round 1, 25 completed Round 2, and 23 completed Round 3. Three statements reached consensus in Round 2 and four statements reached consensus in Round 3, including safe prescribing, guiding choice of drug, adjusting drug doses, identifying risk or prognosis, and reporting/interpreting investigation results.
Conclusions
Many desired clinical applications of AI in emergency medicine have not yet been explored. Clinical and technological experts should co-create new applications to ensure buy-in from all stakeholders. Specialty organizations can lead the way by establishing local clinical priorities.
Why did Vladimir Putin order the invasion of Ukraine in February 2022, despite numerous warnings from Western countries about the consequences of such an action? This article argues that misperceptions about having the upper hand vis-à-vis Western countries, formed and proliferated among the Russian leadership, emboldened the Kremlin to launch the military invasion of Ukraine, assuming that the West would stand down in the face of the attack. Based on a detailed analysis of Russian elites’ discourse through the theoretical lens of interdependence studies, this study demonstrates that Putin miscalculated Western resolve largely because of two key misperceptions. First, Putin’s elites were convinced that the West was asymmetrically dependent on Russia, viewing it as a strategic resource that would tie the hands of Western and EU countries, eventually making them accept the outcome of the war. Second, the Kremlin believed that Ukraine occupied a secondary role in Western interests that would further limit the West’s involvement in the conflict, as it would not risk exposing its dependence on Moscow for the sake of an issue that, in the Kremlin’s eyes, was marginal to European and American security.
This work introduces a novel compact ultra-wideband (UWB) antenna designed for wearable applications, employing a bioinspired structure and machine learning (ML) techniques to achieve exceptional performance in the 3.10–10.42 GHz range. The antenna is fabricated by positioning conductive fabric on a polydimethylsiloxane polymer of 1 mm thickness to augment high flexibility and durability. Additionally, it pioneers integrating a complete ground plane to mitigate back radiation toward the human body, presenting a compact (35.5 × 30.5 × 1 mm3) UWB antenna design compliant with IEEE 802.15.6 standards. The design methodology includes using bandwidth enhancement techniques such as chamfering edges, slots, and adding stubs in the feed, along with applying ML to optimize the antenna’s dimensions for desired return loss characteristics. The proposed antenna demonstrates exceptional resilience to human body loading and physical deformation. The simulation and measurement results have good agreement. The K-nearest neighbour method beat the other ML algorithms maximum accuracy of 99.62% to predict the S11. According to the author’s best knowledge, this is the first compact UWB antenna with full ground specified by IEEE.802.15.6 with ML reported.
Regularization can improve statistical estimates made with highly correlated data. However, any regularization procedure embeds assumptions about the data generating process that can have counterintuitive consequences when those assumptions are untenable. We show that rather than simply shrinking estimates, regularization can reopen backdoor causal paths, inflating the estimates of some effects, and in the wrong circumstances, even reversing their direction. Recently, Cavari and Freedman (2023), argued that declining cooperation rates in surveys have inflated measures of mass polarization. We show that this finding is driven by large penalty terms in their regularized regressions, which leads to the estimates being confounded with time. Alternative methods do not show a clear positive or negative effect of declining cooperation on estimated levels of mass polarization.
The orientation dynamics of inertialess prolate and oblate spheroidal particles in a directly simulated spanwise-rotating turbulent channel flow has been investigated by means of an Eulerian–Lagrangian point-particle approach. The channel rotation and the particle shape were parameterized using a rotation number Ro and the aspect ratio λ, respectively. Eleven particle shapes 0.05 ≤ λ ≤ 20 and four rotation rates 0 ≤ Ro ≤ 10 have been examined. The spheroidal particles retained their almost isotropic orientation in the core region of the channel, despite the significant mean shear rate set up by the Coriolis force. Irrespective of channel rotation rate Ro, rod-like spheroids tend to align in the streamwise direction, while disk-like particles are oriented in the wall-normal direction. These trends were accentuated with increasing departure from sphericity λ = 1. The changeover from the isotropic orientation mode in the centre to the highly anisotropic near-wall orientation mode commenced further away from the suction-side wall with increasing Ro, whereas the particle orientations on the pressure side of the rotating channel remained essentially unaffected by Ro. We observed that the alignments of the fluid rotation vector with the Lagrangian stretching direction were similarly unaffected by the imposed system rotation, except that the de-alignment set in deeper into the core at high Ro. This contrasts with the well-known substantial impact of system rotation on the velocity and vorticity fields. Similarly, slender rods and flatter disks were aligned with the Lagrangian stretching and compression directions, respectively, for all Ro considered, except in the vicinity of the walls. The typical near-wall de-alignment extended considerably further away from the suction-side wall at high Ro. We conjecture that this phenomenon reflects a change in the relative importance of mean shear and small-scale turbulence caused by the Coriolis force. Preferential particle alignment with Lagrangian stretching and compression directions are known from isotropic and anisotropic turbulence in inertial reference systems. The present results demonstrate the validity of this principle also in a non-inertial system.
We use direct numerical simulations to study convection in rotating Rayleigh–Bénard convection in horizontally confined geometries of a given aspect ratio, with the walls held at fixed temperatures. We show that this arrangement is unconditionally unstable to flow that takes the form of wall-adjacent convection rolls. For wall temperatures close to the temperatures of the upper or lower boundaries, we show that the base state undergoes a Hopf bifurcation to a state comprised of spatiotemporal oscillations – ‘wall modes’ – precessing in a retrograde direction. We study the saturated nonlinear state of these modes, and show that the velocity boundary conditions at the upper and lower boundaries are crucial to the formation and propagation of the wall modes: asymmetric velocity boundary conditions at the upper and lower boundaries can lead to prograde wall modes, while stress-free boundary conditions at both walls can lead to wall modes that have no preferred direction of propagation.
Based on correlational and factorial analysis of data collected from 384 middle and high school students in South Korea, Al–Hoorie et al. (2024) claimed the existence of a discriminant validity crisis within the L2 motivational self-system research tradition and advocated for abandoning research in this area. In this response, we critically examined the evidence presented, re-analyzed their data, and argued that their findings actually support the discriminant validity of the target scales. We also discussed issues related to the design and implementation of their study and refuted their assertion regarding a discriminant validity crisis in this field. Finally, we emphasized the necessity of prioritizing definitional validity in the ongoing methodological reforms of L2 motivation research.
The release of ChatGPT in November 2022 drastically lowered the barrier to artificial intelligence with an intuitive web-based interface to a large language model. This study addressed the research problem: “Can ChatGPT adequately triage simulated disaster patients using the Simple Triage and Rapid Treatment (START) tool?”
Methods
Five trained disaster medicine physicians developed nine prompts. A Python script queried ChatGPT Version 4 with each prompt combined with 391 validated patient vignettes. Ten repetitions of each combination were performed: 35190 simulated triages.
Results
A valid START score was returned In 35102 queries (99.7%). There was considerable variability in the results. Repeatability (use of the same prompt repeatedly) was responsible for 14.0% of overall variation. Reproducibility (use of different prompts) was responsible for 4.1% of overall variation. Accuracy of ChatGPT for START was 61.4% with a 5.0% under-triage rate and a 33.6% over-triage rate. Accuracy varied by prompt between 45.8% and 68.6%.
Conclusions
This study suggests that the current ChatGPT large language model is not sufficient for triage of simulated patients using START due to poor repeatability and accuracy. Medical practitioners should be aware that while ChatGPT can be a valuable tool, it may lack consistency and may provide false information.
The potential for a radiological disaster from natural environmental causes, human error, aging nuclear power plants, buried radioactive waste, regular ground transport of radioactive materials, a shared international border, and the threat of radiological terrorism make the Western New York region vulnerable for a radiation emergency. A global threat from Russia and intentional uses of nuclear weapons by non-state approved users, such as North Korea, raise public awareness. Limited importance has been given to educating medical providers and emergency planners with radiological knowledge and preparation.
Objective
The goal of this study was to understand the relationships of the peerception of risk, emergency self-efficacy and willingness to respond to a radiation emergency among health professionals.
Method
Two hundred sixty-nine (269) medical and health practitioners were selected for a purposive, convenience sample in an eight-county region of Western New York. Participants identified the need for improved knowledge and preparation for the management of a radiation emergency.
Results
Statistical findings using the author created Structural Equation Model (SEM) revealed a goodness of fit for perception of risk as a strong predictor of willingness to respond to a radiation emergency.
Conclusion
The SEM study names the variables that influence training for global nuclear realities.