In the early 1980s, a group of radical African economists working at the Dakar-based Institut Africain de Développement Economique et de Planification (IDEP) were dismissed. Among them were three Ghanaian economists, Tony Obeng, Cadman Atta Mills, and Kwame Amoa, who applied a neocolonial analysis of global political economy to critique international development policies. Although the precise circumstances of their dismissal remain unclear, it was evident that their revolutionary approach to development clashed fundamentally with IDEP’s methods. Inspired by Ghanaian President Kwame Nkrumah’s theory of neocolonialism and the Latin American school of dependency theory, these Pan-African scholars refuted the dominant, anti-political, dehistorical, and simplistic Western explanation of Africa’s underdevelopment and urgently searched for better explanations. Drawing on institutional records, working papers, interviews, memos, and published and unpublished papers, this article centers Africans and African institutions engaged in development thinking in the larger history of economic thought in the 1970s and 1980s.

Fix integers $r \ge 2$ and $1\le s_1\le \cdots \le s_{r-1}\le t$ and set $s=\prod _{i=1}^{r-1}s_i$. Let $K=K(s_1, \ldots , s_{r-1}, t)$ denote the complete $r$-partite $r$-uniform hypergraph with parts of size $s_1, \ldots , s_{r-1}, t$. We prove that the Zarankiewicz number $z(n, K)= n^{r-1/s-o(1)}$ provided $t\gt 3^{s+o(s)}$. Previously this was known only for $t \gt ((r-1)(s-1))!$ due to Pohoata and Zakharov. Our novel approach, which uses Behrend’s construction of sets with no 3-term arithmetic progression, also applies for small values of $s_i$, for example, it gives $z(n, K(2,2,7))=n^{11/4-o(1)}$ where the exponent 11/4 is optimal, whereas previously this was only known with 7 replaced by 721.

We study stationary distributions in the context of stochastic reaction networks. In particular, we are interested in complex balanced reaction networks and the reduction of such networks by assuming that a set of species (called non-interacting species) are degraded fast (and therefore essentially absent from the network), implying that some reaction rates are large relative to others. Technically, we assume that these reaction rates are scaled by a common parameter N and let $N\to\infty$. The limiting stationary distribution as $N\to\infty$ is compared with the stationary distribution of the reduced reaction network obtained by elimination of the non-interacting species. In general, the limiting stationary distribution could differ from the stationary distribution of the reduced reaction network. We identify various sufficient conditions under which these two distributions are the same, including when the reaction network is detailed balanced and when the set of non-interacting species consists of intermediate species. In the latter case, the limiting stationary distribution essentially retains the form of the complex balanced distribution. This finding is particularly surprising given that the reduced reaction network could be non-weakly reversible and might exhibit unconventional kinetics.

Autonomy theories of contract are influential and have many attractions, not least their compatibility with liberal ideals. However, such theories cannot account for basic features of the common law of contract, in particular: the role of established transaction types, the doctrine of consideration and the phenomenon of contractual obligation. An exchange theory of contract can account for those features of the law. This theory’s liberal credentials can be established by connecting it to an alternative intellectual strand in the liberal tradition, sometimes known as commercial liberalism.

Gas turbine maintenance strategy relies heavily on accurate estimation of critical component life consumption of gas turbine engines during their operations. The equivalent operating hours (EOH) is a useful concept to measure the engine life consumption and support condition-based maintenance planning for gas turbine engines and their critical components. However, the current EOH calculation methods are mostly empirical and engine-specific, relying on vast operating data and experience. This paper introduces a novel physics-based method to estimate the EOH of the high-pressure turbine rotor blades of a gas turbine engine based on the damages caused by creep and low-cycle fatigue (creep-LCF) interactions. The method has been applied to a typical turbofan engine taking both 440-minute long-haul flight at one flight per day and 60-minute short-haul flight at two flights per day. A comparison of the predicted damages and life consumptions indicates that the creep EOH and also the creep damage of the engine of the short-haul aircraft is about 1.38 times that of the engine of the long-haul aircraft, the LCF equivalent operating cycles (EOC) and also the LCF damage of the engine of the short-haul aircraft is about 2.0 times that of the engine of the long-haul aircraft, and the total damages are more affected by the creep damage than the LCF damage with the creep damage being 6.78 times the LCF damage for the engine of the short-haul aircraft and 9.81 times for the engine of the long-haul aircraft. In addition, the total EOH or the total damage of the engine of the short-haul aircraft is about 1.44 times that of the engine of the long-haul aircraft. The proposed method shows a great potential to provide a quick estimate of the life consumption of gas turbine engines for condition monitoring, and it can be applied to other types of gas turbine engines.

The money exchange model is a type of agent-based model used to study how wealth distribution and inequality evolve through monetary exchanges between individuals. The primary focus of this model is to identify the limiting wealth distributions that emerge at the macroscopic level, given the microscopic rules governing the exchanges among agents. In this paper, we formulate generalized versions of the immediate exchange model, the uniform reshuffling model, and the uniform saving model, all of which are types of money exchange model, as discrete-time interacting particle systems and characterize their stationary distributions. Furthermore, we prove that, under appropriate scaling, the asymptotic wealth distribution converges to an exponential distribution for the uniform reshuffling model, and to either an exponential distribution or a gamma distribution depending on the tail behavior of the number of coins given/saved in the immediate exchange model and the random saving model, which generalizes the uniform saving model. In particular, our results provide a mathematically rigorous formulation and generalization of the assertions previously predicted in studies based on numerical simulations and heuristic arguments.

Persistent ductus venosus is an extremely rare disease that causes liver failure, hypoxaemia, and encephalopathy. We report the successful treatment of our patient with elevated transaminase and ammonia levels due to patent ductus venosus, diagnosed in the neonatal period and treated with a vascular plug device.

To investigate the advantages and disadvantages of two multi-swirl fuel-rich dome configurations, namely the triple-swirler and double-swirler, for a novel high-temperature rise centre-staged combustor, this study employed ANSYS Fluent software. Utilising the Reynolds-averaged Navier-Stokes (RANS) equation as the governing equation, three-dimensional numerical simulations were conducted using the Realisable k-ε turbulence model and non-premixed probability density function (PDF) combustion model to analyse the flow and combustion characteristics of both configurations. A comparative study was then performed to evaluate the performance differences between the two dome configurations under take-off and idle conditions. The results demonstrate that, under both conditions, the fuel-air mixing in the triple-swirler combustor occurs faster and more uniformly. Specifically, during takeoff, the primary zone temperature distribution in the triple-swirler combustor is more uniform, while during idle, the fuel-rich combustion region is more symmetrical. Furthermore, across both conditions, the outlet temperature distribution of the triple-swirler combustor is of superior quality, albeit with equivalent combustion efficiency. Notably, the formation of NOx and soot in the triple-swirler combustor, during takeoff conditions, exceeds that of the double-stage combustor along the flow path, whereas the generation of CO and UHC, during idle conditions, is lower in the former.

Maritime safety faces growing challenges due to an expanding global fleet, tighter schedules, and increasingly complex stakeholder interactions. This study integrates multiple data sources to determine a more accurate representation of major marine accident causative factors in the United Kingdom. Logistic regression and data modelling are applied to Automatic Identification System data (2011–2017) and reported accidents from the Marine Accident Investigation Branch (2013–2019). Results show that larger vessels, daytime transits, service ships, winter conditions, and confined high-density areas such as ports impact accident likelihood. Interviews validate the data and emphasize the influence of port geometry and channel complexity. Among major UK ports, London, Plymouth and Milford Haven exhibit the highest accident-to-traffic densities. While maritime regulations and safety management systems in ports and vessels are seen as adequate by industry professionals, human factors require the greatest attention to improve maritime safety.

This article examines the early Nazi movement through the contested and violent politics of Munich’s beer halls between 1919 and 1923. It argues that these spaces were not neutral stages for political speech, but rather central arenas in which the movement defined its identity, tested its tactics, and fused party and paramilitary organization. Drawing on police reports, eyewitness accounts, and Nazi publications, the article shows how the NSDAP sought to recode beer halls into sites of antisemitic and anti-republican action, aided by the toleration and complicity of Bavarian state authorities. These spaces became laboratories for masculine bonding, crowd mobilization, and practices of exclusionary violence that made the boundaries of the Volk both visible and enforceable. By foregrounding the interplay of space, sociability, and violence, the article reframes the origins of Nazi radicalism and highlights the role of everyday venues in shaping interwar populist politics.

Fiscal rules for devolved nations present some fundamental challenges not faced when making national fiscal Rules. Most importantly, rules across devolved nations involve a negotiation between the central and devolved governments who have very different objectives and so the framework created ends up as a mix of economics, politics and the vagaries of compromise. This article highlights how these issues have resulted in Scotland finances being heavily influenced by both inflation and population growth in ways that were never intended to become a long run feature of the funding framework.