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We report an unusual variant of obstructed supra cardiac anomalous pulmonary venous drainage where the vertical vein is obstructed by a vice formed between the persistent arterial duct and the left pulmonary artery.
This article extends the previous investigation of the spatial evolution of energy-containing motions in wall-bounded turbulent flows (Kannadasan et al., J. Fluid Mech., vol. 955, 2023, R1) by examining their scale-interactions through spectral analysis based on the spanwise scale decomposition of turbulent kinetic energy and the Reynolds stress transport equation. The energy-containing motions located at the inflow of a turbulent channel flow are artificially removed and the interscale transport mechanisms involved in their spatial evolution are studied. This scale interaction analysis reveals the presence of a significant inverse transfer of streamwise Reynolds stress from the near-wall streaks to larger scales in the spatial evolution of energy-containing motions. This transfer is due to the spanwise variation of streamwise velocity fluctuations, represented by $\partial u'/\partial z$, which is the primary mechanism of streak instability. The analysis presented in this study also shows that the inverse cascade of spanwise energy may correspond to the regeneration of streamwise vortices in the process of reactivating the self-sustaining mechanism in the spatial evolution of energy-containing motions.
“Later” crusading has become a vibrant field in recent years, with a concern for our core theme, “patterns of conflict and negotiation,” at its center. Often, and rightly enough, those patterns have been focused on matters of high politics and diplomacy, military affairs, papal propaganda, and more. The approach adopted here complements these efforts by modulating their perspectives. This article explores patterns of conflict and negotiation as they played out in the realms of crusading experience, culture, and memory in the wake of the fall of Constantinople (1453) and the siege of Belgrade (1456). It does so through the lens of those particularly rich, but also challenging, fifteenth-century manuscript sources known as “miscellanies.”
Introducing a pair-parameter matrix Mittag–Leffler function, we study the uniqueness and Hyers–Ulam stability to a new fractional nonlinear partial integro-differential equation with variable coefficients and a mixed boundary condition using Banach’s contractive principle as well as Babenko’s approach in a Banach space. These investigations have serious applications since uniqueness and stability analysis are essential topics in various research fields. The techniques used also work for different types of differential equations with initial or boundary conditions, as well as integral equations. Moreover, we present a Python code to compute approximate values of our newly established pair-parameter matrix Mittag–Leffler functions, which extend the multivariate Mittag–Leffler function. A few examples are given to show applications of the key results obtained.
We characterised the soils and vegetation in 15 sets of four quadrats on and around mounds of Macrotermes annandalei (Isoptera, Macrotermitinae) on a plain of deep dystric clay over limestone in Deciduous Dipterocarp Forest in Northern Thailand. Termites have excavated the mounds from the deep calcareous substrate. The mound soils have darker subsoils, larger contents of clays and exchangeable cations, and higher pH values than the surrounding dystric clay loams. The thickets on the mounds are visually different from the surrounding Deciduous Dipterocarp Forest. They have few dipterocarps and are floristically similar to the regionally important Mixed Deciduous Forest. The clear visual differences are confirmed by floristic similarity, cluster, and canonical correspondence analyses for each of the tree, sapling and seedling size classes. The differences between the mound clays and surrounding red clay loams and the associations between soil and forest types are confirmed by ‘t tests’ and the significant correlations of the soil base status with the main floristic axis of the canonical correspondence analyses. Soil variability due to termites and other agents of pedoturbation can significantly contribute to short-range floristic and structural diversity in some dry tropical forests.
Child nutrition, health and development are closely tied to maternal nutrition, health and well-being. The underlying drivers of poor maternal and child nutritional outcomes in sub-Saharan Africa are structural in nature. These risks include social, economic, and environmental factors that together compound vulnerability to poor outcomes. Poverty, as a driver of poor maternal and child health outcomes, is an important determinant that is both a cause and a consequence of malnutrition. The United Nations’ Children’s Fund (UNICEF)’s conceptual model for determinants of maternal and child nutrition outcomes released in 2020, is the agency’s latest iteration of child nutrition frameworks. The model identifies the underlying causes of malnutrition as extending beyond food and diets, to include household level dynamics, maternal factors, and the external environment. The manuscript discusses UNICEF’s conceptual model and its applicability in sub-Saharan Africa. It also considers the evidence on interventions aimed at addressing maternal and child nutrition in the region and the location of social protection among these policy tools, with a special focus on the extent to which these resonate with the conceptual model. It concludes by considering the conditions required for social protection instruments to work in the region and similar settings in the Global South. In this way, the manuscript provides a critical reflection about the role of social protection as a nutrition-sensitive instrument in sub-Saharan Africa, in the context of maternal and child nutrition outcomes.
Genes involved in melanin production directly impact insect pigmentation and can affect diverse physiology and behaviours. The role these genes have on sex behaviour, however, is unclear. In the present study, the crucial melanin pigment gene black was functionally characterised in an urban pest, the German cockroach, Blattella germanica. RNAi knockdown of B. germanica black (Bgblack) had no effect on survival, but did result in black pigmentation of the thoraxes, abdomens, heads, wings, legs, antennae, and cerci due to cuticular accumulation of melanin. Sex-specific variation in the pigmentation pattern was apparent, with females exhibiting darker coloration on the abdomen and thorax than males. Bgblack knockdown also resulted in wing deformation and negatively impacted the contact sex pheromone-based courtship behaviour of males. This study provides evidence for black function in multiple aspects of B. germanica biology and opens new avenues of exploration for novel pest control strategies.
For an odd prime $p$, we consider free actions of $(\mathbb {Z}_{/{p}})^2$ on $S^{2n-1}\times S^{2n-1}$ given by linear actions of $(\mathbb {Z}_{/{p}})^2$ on $\mathbb {R}^{4n}$. Simple examples include a lens space cross a lens space, but $k$-invariant calculations show that other quotients exist. Using the tools of Postnikov towers and surgery theory, the quotients are classified up to homotopy by the $k$-invariants and up to homeomorphism by the Pontrjagin classes. We will present these results and demonstrate how to calculate the $k$-invariants and the Pontrjagin classes from the rotation numbers.
The topology of turbulent coherent structures is known to regulate the transport of energy, mass and momentum in the atmospheric boundary layer (ABL). While previous research has primarily focused on characterizing the structure of turbulence in stationary ABL flows, real-world scenarios frequently deviate from stationarity, giving rise to nuanced and poorly understood changes in the turbulence geometry and associated transport mechanisms. This study sheds light on this problem by examining topological changes in ABL turbulence induced by non-stationarity and their effects on momentum transport. Results from a large-eddy simulation of pulsatile open channel flow over an array of surface-mounted cuboids are examined. The analysis reveals that the flow pulsation triggers a phase-dependent shear rate, and the ejection-sweep pattern varies with the shear rate during the pulsatile cycle. From a turbulence structure perspective, it is attributed to the changes in the geometry of hairpin vortices. An increase (decrease) in the shear rate intensifies (relaxes) these structures, leading to an increase (decrease) in the frequency of ejections and an amplification (reduction) of their percentage contribution to the total momentum flux. Furthermore, the size of the hairpin packets undergoes variations, which depend on the geometry of the constituting hairpin vortices, yet the packet inclination preserves its orientation throughout the pulsatile cycle. These observations reinforce the important role non-stationarity holds in shaping the structure of ABL turbulence and the momentum transport mechanisms it governs.
In July 2022, on the sidelines of the 41st Ordinary Session of the Executive Council of the African Union and the 4th Mid-Year Coordination Summit in Lusaka, Zambia, Heads of state and government, and leaders of delegations of African Union Member States called on member states, African Union through Africa CDC, and partners to recognize, prioritize, and accelerate the establishment and strengthening of public health emergency operation centers (PHEOCs) in the context of health security and in line with Africa’s new public health order. Implementing the declaration requires a multi-dimensional approach that spans across governance, operational capabilities, partnerships, workforce development, and sustainable financing.
It is widely agreed that the increased polarization many countries experience is bad for democracy. However, existing assessments of how polarization affects democracy operate with simplified understandings of both polarization and democracy. Bringing empirical studies and democratic theory into dialogue, I argue that polarization cannot be understood as a single phenomenon that can be evaluated in one way. Moreover, its different kinds affect different parts of the democratic system in distinct ways. First, we must distinguish between the degree of polarization in a given context and the different kinds of polarization at play. Second, we must consider whether people have good reasons for their polarizing behavior or whether it is entirely irrational. If people have good reasons for their polarizing behavior, the problem lies elsewhere than in polarization itself. Third, we must distinguish between the content of polarized opinions and the process of opinion formation. Both can be assessed with democratic criteria, but they raise different questions. Finally, for democratic evaluation it matters where polarization occurs and thus, we must differentiate between different sites of polarization: civil society, election campaigns, and legislatures. I recommend a systemic approach to assessing the democratic implication of polarization, which analyzes both the effects of polarization at different sites and on democracy as a composite whole.
Foreign workers were a common feature in the economy of postwar Czechoslovakia in various periods of the second half of the twentieth century. This article focuses on foreign labor practices during the first economic plans, namely the two-year plan and the first five-year plan between 1947 and 1950. The number of foreign workers at this time didn't exceed twenty thousand persons and their stays in the country were, with only individual exceptions, short. Workers, who found employment in Czechoslovak agriculture and industry in this period, came from different countries including neighboring Poland, Bulgaria, and Romania, but also from Italy. Recruitment of other groups such as workers from Hungary, the Netherlands, or even China is also considered by the article. These foreign laborers worked in Czechoslovakia under various conditions depending on their methods of recruitment and contracting, the duration of their employment, and other important factors. The basic question this article aims to answer is what the role of Gastarbeit was in Czechoslovakia's communist economic policy. It also examines the motivations of countries that sent workers as well as those of the workers themselves. Finally, the article also attempts to analyze the opportunities and limits of these workers’ strategies in the Czechoslovak labor market.
The molten sand that is a mixture of calcia, magnesia, alumina and silicate, known as CMAS, is characterized by its high viscosity, density and surface tension. The unique properties of CMAS make it a challenging material to deal with in high-temperature applications, requiring innovative solutions and materials to prevent its buildup and damage to critical equipment. Here, we use multiphase many-body dissipative particle dynamics simulations to study the wetting dynamics of highly viscous molten CMAS droplets. The simulations are performed in three dimensions, with varying initial droplet sizes and equilibrium contact angles. We propose a parametric ordinary differential equation (ODE) that captures the spreading radius behaviour of the CMAS droplets. The ODE parameters are then identified based on the physics-informed neural network (PINN) framework. Subsequently, the closed-form dependency of parameter values found by the PINN on the initial radii and contact angles are given using symbolic regression. Finally, we employ Bayesian PINNs (B-PINNs) to assess and quantify the uncertainty associated with the discovered parameters. In brief, this study provides insight into spreading dynamics of CMAS droplets by fusing simple parametric ODE modelling and state-of-the-art machine-learning techniques.
To compare ultrasonography-guided drainage versus conventional surgical incision and drainage in deep neck space abscesses.
Methods
The study was pre-registered on the National Institute of Health Research Prospective Register of Systematic Reviews (CRD42023466809) and adhered to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The Medline, Embase and Central databases were searched. Primary outcomes were length of hospital stay and recurrence. Heterogeneity and bias risk were assessed, and a fixed-effects model was applied.
Results
Of 646 screened articles, 7 studies enrolling 384 participants were included. Ultrasonography-guided drainage was associated with a significantly shorter hospital stay (mean difference = −2.31, p < 0.00001), but no statistically significant difference was noted in recurrence rate compared to incision and drainage (odds ratio = 2.02, p = 0.21). Ultrasonography-guided drainage appeared to be associated with cost savings and better cosmetic outcomes.
Conclusion
Ultrasonography-guided drainage was associated with a shorter hospital stay, making it a viable and perhaps more cost-effective alternative. More randomised trials with adequate outcomes reporting are recommended to optimise the available evidence.
The local structure of rotationally symmetric Finsler surfaces with vanishing flag curvature is completely determined in this paper. A geometric method for constructing such surfaces is introduced. The construction begins with a planar vector field X that depends on two functions of one variable. It is shown that the flow of X could be used to generate a generalized Finsler surface with zero flag curvature. Moreover, this generalized structure reduces to a regular Finsler metric if and only if X has an isochronous center. By relating X to a Liénard system, we obtain the isochronicity condition and discover numerous new examples of complete flat Finsler surfaces, depending on an odd function and an even function.