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Dietary intake of long-chain n-3 PUFA (n-3 PUFA), particularly EPA and DHA, has been associated with psychological well-being, but little is known about the n-3 PUFA intake of homeless youth. The current study determined the association between depression and anxiety symptoms and n-3 PUFA intake and erythrocytes status in homeless youth. Totally, 114 homeless youth aged 18–24 years were recruited from a drop-in centre. n-3 PUFA dietary intake was assessed using an FFQ, and erythrocytes status was determined by gas chromatography (GC). Linear regression models were used to determine the relationship between psychological well-being and n-3 PUFA intake and status. The mean intakes of EPA and DHA for all participants (0·06 ± 0·13 g/d and 0·11 ± 0·24 g/d) were well below recommended levels, and mean erythrocytes EPA + DHA (n-3 index) in the cohort (2·42 %) was lower than reported for healthy, housed adolescents and those with clinical depression. There was no association of n-3 PUFA intake and erythrocytes status with either depression or anxiety. However, the relationships of depression with dietary EPA (P = 0·017) and DHA (P = 0·008), as well as erythrocytes DHA (P = 0·007) and n 3-index (P = 0·009), were significantly moderated by sex even after adjusting for confounders. Specifically, among females, as the intake and status of these n-3 PUFA decreased, depression increased. Our findings show poor dietary intake and low erythrocytes status of n-3 PUFA among homeless youth, which is associated with depressive symptoms among females.
This paper investigates the effect of the optimised morphing leading edge (MLE) and the morphing trailing edge (MTE) on dynamic stall vortices (DSV) for a pitching aerofoil through numerical simulations. In the first stage of the methodology, the optimisation of the UAS-S45 aerofoil was performed using a morphing optimisation framework. The mathematical model used Bezier-Parsec parametrisation, and the particle swarm optimisation algorithm was coupled with a pattern search with the aim of designing an aerodynamically efficient UAS-45 aerofoil. The $\gamma - R{e_\theta }$ transition turbulence model was firstly applied to predict the laminar to turbulent flow transition. The morphing aerofoil increased the overall aerodynamic performances while delaying boundary layer separation. Secondly, the unsteady analysis of the UAS-S45 aerofoil and its morphing configurations was carried out and the unsteady flow field and aerodynamic forces were analysed at the Reynolds number of 2.4 × 106 and five different reduced frequencies of k = 0.05, 0.08, 1.2, 1.6 and 2.0. The lift (${C_L})$, drag (${C_D})$ and moment (${C_M})\;$coefficients variations with the angle-of-attack of the reference and morphing aerofoils were compared. It was found that a higher reduced frequencies of 1.2 to 2 stabilised the leading-edge vortex that provided its lift variation in the dynamic stall phase. The maximum lift $\left( {{C_{L,max}}} \right)$ and drag $\left( {{C_{D,max}}} \right)\;$coefficients and the stall angles of attack are evaluated for all studied reduced frequencies. The numerical results have shown that the new radius of curvature of the MLE aerofoil can minimise the streamwise adverse pressure gradient and prevent significant flow separation and suppress the formation of the DSV. Furthermore, it was shown that the morphing aerofoil delayed the stall angle-of-attack by 14.26% with respect to the reference aerofoil, and that the ${C_{L,max}}\;$of the aerofoil increased from 2.49 to 3.04. However, while the MTE aerofoil was found to increase the overall lift coefficient and the ${C_{L,max}}$, it did not control the dynamic stall. Vorticity behaviour during DSV generation and detachment has shown that the MTE can change the vortices’ evolution and increase vorticity flux from the leading-edge shear layer, thus increasing DSV circulation. The conclusion that can be drawn from this study is that the fixed drooped morphing leading edge aerofoils have the potential to control the dynamic stall. These findings contribute to a better understanding of the flow analysis of morphing aerofoils in an unsteady flow.
There has always been a debate about the location and role of women during the persecution of Christians under Mwanga II’s first reign as Kabaka of Buganda. Kabaka is the Luganda equivalent of the English word king. The debate is partly fueled by a total absence of women from the pictures of Ugandans historically referred to as the Uganda Martyrs. This paper uses archival research to tell the story of an African woman who, in her adult life, married two devout Anglicans, in whose lives she was actively involved, laying a foundation for Uganda’s Anglican tradition. Evidence shows the first Anglican baptism, teacher and burial in Uganda are traced to her first marriage, which ended in early 1884 with the death of her husband from smallpox. Nakimu Nalwanga Sarah would have been the first martyr if not for the timely discovery that she was Mwanga’s relative. Still, as a punishment, she was ordered to witness the cruel burning of the first martyrs on January 31, 1885. She married again in a marriage that produced Uganda’s first catechist, deacon and priest. Her second husband was part of a team that completed the translation of the first Luganda Bible in 1895.
We investigate the nonlinear evolution of pairs of three-dimensional, equal-sized and opposite-signed vortices at finite Froude and Rossby numbers. The two vortices may be offset in the vertical direction. The initial conditions stem from relative equilibria obtained numerically in the quasi-geostrophic regime, for vanishing Froude and Rossby numbers. We first address the linear stability of the quasi-geostrophic opposite-signed pairs of vortices, and show that for all vertical offsets, the vortices are sensitive to an instability when close enough together. In the nonlinear regime, the instability may lead to the partial destruction of the vortices. We then address the nonlinear interaction of the vortices for various values of the Rossby number. We show that as the Rossby number increases, destructive interactions, where the vortices break into pieces, may occur for a larger separation between the vortices, compared to the quasi-geostrophic case. We also show that for well-separated vortices, the interaction is non-destructive, and ageostrophic effects lead to the deviation of the trajectory of the pair of vortices, as the anticyclonic vortex dominates the interaction. Finally, we show that the flow remains remarkably close to a balanced state, emitting only waves containing negligible energy, even when the interaction leads to the destruction of the vortices.
In the context of linear stability analysis, considering unsteady base flows is notoriously difficult. A generalisation of modal linear stability analysis, allowing for arbitrarily unsteady base flows over a finite time, is therefore required. The recently developed optimally time-dependent (OTD) modes form a projection basis for the tangent space. They capture the leading amplification directions in state space under the constraint that they form an orthonormal basis at all times. The present numerical study illustrates the possibility to describe a complex flow case using the leading OTD modes. The flow under investigation is an unsteady case of the Blasius boundary layer, featuring streamwise streaks of finite length and relevant to bypass transition. It corresponds to the state space trajectory initiated by the minimal seed; such a trajectory is unsteady, free from any spatial symmetry and shadows the laminar–turbulent separatrix for a finite time only. The finite-time instability of this unsteady base flow is investigated using the 8 leading OTD modes. The analysis includes the computation of finite-time Lyapunov exponents as well as instantaneous eigenvalues, and of the associated flow structures. The reconstructed instantaneous eigenmodes are all of outer type. They map unambiguously the spatial regions of largest instantaneous growth. Other flow structures, previously reported as secondary, are identified with this method as relevant to streak switching and to streamwise vortical ejections. The dynamics inside the tangent space features both modal and non-modal amplification. Non-normality within the reduced tangent subspace, quantified by the instantaneous numerical abscissa, emerges only as the unsteadiness of the base flow is reduced.
The present study investigated the horizontal and vertical distribution of meiofauna community and Nematoda assemblages on two sandy beaches and two muddy tidal flats in a freshwater Amazon estuary governed by mesotides. Meiofauna density was significantly higher in muddy environments, explained by the higher food availability. On the one hand, there was no difference between sediment layers in both sandy environments, which suggests that individuals must have migrated to layers deeper than 10 cm. On the other, the highest densities and richness in muddy environments occurred in the upper layer due to higher food and oxygen availability in the surface sediment layer, which decreases with depth. Muddy environments differed on both beaches; they had the highest nematode genera densities and richness. This might be explained by the high nutrient enrichment in these environments. There was no significant difference in Nematoda density and richness between zones in any environment, likely due to the small mid-littoral extension (<40 m), which did not favour the high spatial variability of genera. Nematoda density was higher at a depth of 0–2 cm in both muddy environments, explained by the availability of oxygen and food. The high abundance of deposit-feeder genera in muddy environments indicates high organic enrichment, whereas the distribution of trophic types was more homogeneous on the beaches where abiotic factors tended to be more structuring than food availability.
This article summarises the research, protection, enhancement and awareness-raising activities carried out on coastal and submerged archaeological sites and wrecks discovered on the northern and Cap Bon coasts in Tunisia. The objective of these activities is to better understand and protect the underwater cultural heritage, while ensuring its preservation for future generations. The article also highlights the policy put in place by the supervisory institution to ensure an integrated and sustainable management of this heritage, despite the challenges it faces, in accordance with the principles of the 2001 UNESCO Convention on the Protection of the Underwater Cultural Heritage, ratified by Tunisia in 2009. Furthermore, the article stresses the importance of coordinating the conservation of this heritage with local development, while promoting responsible tourism practices, as part of Tunisia's active search to enhance its tourism and cultural potential – as a source of sustainable development in the coastal and maritime areas concerned.
The near wake of a hemisphere immersed in a laminar boundary layer is studied utilizing time-resolved tomographic particle image velocimetry (TPIV). Focus is placed on the three-dimensional vortical structures and the formation details of hairpin vortices before the onset of transition. The three-dimensional instantaneous pressure field of the hemisphere wake is reconstructed for better understanding the flow mechanism. Experiments are carried out with Reynolds number $Re_{r}=1370$, based on the hemisphere radius $R$. Features of periodicity of the near wake are analysed using proper orthogonal decomposition and Fourier transformation. The velocity fluctuation in the wall-normal direction is shown to be crucial to the formation of hairpin vortices in the near wake. By investigating the transport of mass and vorticity, and the correlation between pressure and hairpin vortex strength, the formation mechanism is revealed clearly. Specifically, the main hairpin vortices (MHVs) are formed within the reaction of outer high-speed flow and near-wall flow. The formation of the head portion is followed by the leg portion formation. The shedding of the MHVs is highly correlated with the pressure, as well as the pressure gradient in the wall-normal direction. For the side hairpin vortices (SHVs), the leg portion is formed first, followed by the generation of the head portion thanks to induction of the re-oriented standing vortices. The generation of the SHVs can be regarded as the downstream bridging of the standing vortices, similar to the generation of hairpin vortices due to the connection of streamwise vortices in turbulent boundary layers.
In this paper, I consider the objection that unilateral secession by a national group (e.g., the Scots) from a legitimate, nonusurping state would wrong minority nationalities within the seceding territory. I show first that most proponents of this objection assume that the ground of the right to national self-determination is the protection of the group’s culture. I show that there are alternative justifications available. I then set out a version of this objection that does not rely on this claim; on this objection, a national minority that seceded and created its own state would commit an expressive wrong against minorities within the territory over which it claimed jurisdiction. I show that this objection is undermotivated: only under a specific set of circumstances would the minorities of the secessionist region be subject to an expressive wrong. Finally, I show that the correct way to think about the claims of minorities in secessionist regions is in terms of a claim to secure access to equal civic status such that they are not at risk of becoming justifiably alienated from their new state. If a secessionist group cannot provide this guarantee to the minority residents of their territory, then their seceding would commit wrongful harm, and the presumption in favour of collective autonomy is defeated. I call this defeater the ‘Alienation Defeater.’
With this in hand, we are now in a position to explain why nations are normatively special. Responding to the objections broached by Allen Buchanan and others, I show that even if other kinds of groups, such as religious groups, have the features in virtue of which nations have a claim to self-determination, this does not entail that those groups also have the right to secede. This is because an account of self-determination needs a list of ‘defeaters’—features in virtue of which a group’s claim to self-determination is defeated. I argue that religious groups are the strongest candidate for having a claim to collective autonomy in virtue of sharing many features with nations. I then argue that religious groups will run afoul of the Alienation Defeater; religious identity is too narrow to be the basis of the dominant collective identity of a state. This does not apply to nationality. This, I explain, is because of qualitative differences between religious groups, qua religious groups, and nations.
The COVID-19 pandemic and associated lockdowns were predicted to have a major impact on suicidal behaviour, including self-harm. However, current studies have produced contradictory findings with limited trend data.
Aims
Nine years of linked individual-level administrative data were utilised to examine changes in hospital-presenting self-harm and ideation (thoughts of self-harm or suicide) before and during the pandemic.
Method
National self-harm registry data were linked to demographic and socioeconomic indicators from healthcare registration records (n = 1 899 437). Monthly presentations of self-harm or ideation were split (pre-COVID-19 restrictions: April 2012 to February 2020; and during restrictions: March to September 2020). Auto-regressive integrated moving average (ARIMA) models were trained in R taking into consideration trends and seasonal effects. Forecast (‘expected’) monthly values were compared with ‘actual’ values, stratified by demographic factors and method of harm.
Results
The number of individuals presenting with self-harm or ideation dropped significantly at the beginning of the pandemic (March–May 2020), before returning mostly to expected trends from June 2020. Stratified analysis showed similar presentation trends across most demographic subgroups except for those aged over 65 years, living alone or in affluent areas, where presentations remained unaffected, and those aged under 16 years, where numbers presenting with self-harm or ideation increased above expected levels.
Conclusions
Although population trends show an overall drop in presentations before a return to ‘normal’ from June 2020, the demographic profile of those presenting with self-harm or ideation varied significantly, with increases in children under the age of 16 years. This highlights important potential target groups who may have been most negatively affected by the pandemic.
The current study aimed to investigate the cardiovascular effects of epicatechin, a flavonoid found in green tea and cocoa, in attenuating complications associated with metabolic syndrome in diet-induced obese rats. Male Wistar-Kyoto (WKY) rats aged 16 weeks were fed either standard rat chow or given a high-fat-high-carbohydrate (HFHC) diet for 20 weeks. Epicatechin treatment (5 mg/kg/d) was administered to a subset of WKY rats commencing at week 8 of the 20 week HFHC feeding period. Body weights, food, water and energy intakes, blood pressure, heart rate and glucose tolerance were measured throughout the treatment period. Oxidative stress and inflammatory markers, lipid levels, cardiac collagen deposition, cardiac electrical function, aortic and mesenteric vessel reactivity were examined after the treatment. Twenty weeks of HFHC feeding in WKY rats resulted in the development of metabolic syndrome indicated by the presence of abdominal obesity, dyslipidaemia, glucose intolerance and increased blood pressure. Epicatechin treatment was found to enhance the oxidative stress status in HFHC groups through an increase in serum nitric oxide levels and a decrease in 8-isoprostane concentrations. Furthermore, WKY-HFHC rats displayed a decrease in IL-6 levels. The lipid profiles in HFHC groups showed improvement, with a decrease in LDL-cholesterol and TAG and an increase in HDL-cholesterol levels observed in WKY-HFHC rats. However, epicatechin was not effective in preventing weight gain, glucose intolerance or hypertension in HFHC fed rats. Overall, the results of this study suggest that epicatechin has the potential to improve the underlying mechanisms associated with metabolic syndrome in obese rats.
The rapid widening of wealth inequalities has led to sharp differences in living standards in Great Britain. Understanding whether and separately the rate at which individuals accumulate particular types of wealth by family background is important for improving wealth and social mobility. We show offspring wealth inequality is driven by housing wealth, and holding such wealth is becoming increasingly associated with early life circumstances relating to parental housing tenure and education, even after controlling for adult offspring’s own characteristics. Importantly, we find adult offspring whose parents hold a degree and are homeowners are no less likely to report homeownership and housing wealth compared to older cohorts from the same background. Our findings infer the intergenerational rank correlation in housing wealth is set to double in approximately three decades.
Droplet coalescence is a common phenomenon and plays an important role in multidisciplinary applications. Previous studies mainly consider the coalescence of miscible liquids, even though the coalescence of immiscible droplets on a solid surface is a common process. In this study, we explore the coalescence of two immiscible droplets on a partial wetting surface experimentally and theoretically. We find that the coalescence process can be divided into three stages based on the time scales and force interactions involved, namely (I) the growth of a liquid bridge, (II) the oscillation of the coalescing sessile droplet and (III) the formation of a partially engulfed compound sessile droplet and the subsequent retraction. In stage I, the immiscible interface is found not to affect the scaling of the temporal evolution of the liquid bridge, which follows the same 2/3 power law as that of miscible droplets. In stage II, by developing a new capillary time scale considering both surface and interfacial tensions, we show that the interfacial tension between the two immiscible liquids functions as a non-negligible resistance to the oscillation which decreases the oscillation periods. In stage III, a modified Ohnesorge number is developed to characterize the visco-capillary and inertia-capillary time scales involved during the displacement of water by oil; a new model based on energy balance is proposed to analyse the maximum retraction velocity, highlighting that the viscous resistance is concentrated in a region close to the contact line.
The deleterious effects of adversity are likely intergenerational, such that one generation’s adverse experiences can affect the next. Epidemiological studies link maternal adversity to offspring depression and anxiety, possibly via transmission mechanisms that influence offspring fronto-limbic connectivity. However, studies have not thoroughly disassociated postnatal exposure effects nor considered the role of offspring sex. We utilized infant neuroimaging to test the hypothesis that maternal childhood maltreatment (CM) would be associated with increased fronto-limbic connectivity in infancy and tested brain-behavior associations in childhood. Ninety-two dyads participated (32 mothers with CM, 60 without; 52 infant females, 40 infant males). Women reported on their experiences of CM and non-sedated sleeping infants underwent MRIs at 2.44 ± 2.74 weeks. Brain volumes were estimated via structural MRI and white matter structural connectivity (fiber counts) via diffusion MRI with probabilistic tractography. A subset of parents (n = 36) reported on children’s behaviors at age 5.17 ± 1.73 years. Males in the maltreatment group demonstrated greater intra-hemispheric fronto-limbic connectivity (b = 0.96, p= 0.008, [95%CI 0.25, 1.66]), no differences emerged for females. Fronto-limbic connectivity was related to somatic complaints in childhood only for males (r = 0.673, p = 0.006). Our findings suggest that CM could have intergenerational associations to offspring brain development, yet mechanistic studies are needed.
Histories of conservation suggest that from the nineteenth century onwards, the custodianship and conservation of colonial antiquities enabled European powers to legitimize imperial claims. This article complicates this view by focusing on a series of visits made by British royals to the Caves of Elephanta, near Bombay, as part of their tours of India. Of particular interest are the visits in 1870 and 1875, which were essentially picnics, including fireworks and feasting, with little showcasing of ongoing conservation efforts. The article argues that these early visits also sought to advance a narrative of imperial legitimization through the British heirs’ presence at an Indian monument. Rather than acts of rational governance, such as conservation measures, these picnics were transactions within the ceremonial economy that privileged consumption as a means of legitimizing empire. They present a register of imperial engagement with an Indian monument that is neither ‘plunder’ nor ‘preservation’. Instead, they are posited as predecessors of the durbars (courts/assemblies) produced by the British administration from 1877 onwards. As acts of imperial political communication, the Elephanta visits drew upon the popularity of the picnic as a form of leisure, and consumption, and the long-standing aesthetic resonances of the site, such as the island’s picturesque framing and the Caves’ Romanticist associations. These enduring aesthetic frameworks made the acts of consumption legible as imperial political communication. The picnics at Elephanta demonstrate that colonial antiquities featured in imperial narratives of legitimization based on political pageantry, exceeding conservation and rational governance.
Kazal-type serine protease inhibitors (KaSPI) play important roles in insect growth, development, digestion, metabolism and immune defence. In this study, based on the transcriptome of Mythimna separata, the cDNA sequence of MsKaSPI with Kazal domain was uploaded to GenBank (MN931651). Spatial and temporal expression analysis showed that MsKaSPI was expressed at different developmental stages and different tissues, and it was induced by 20-hydroxyecdysone in third-instar larvae of M. separata. After 24 h infection by Beauveria bassiana, the expression level of MsKaSPI and the corresponding MsKaSPI content were significantly up-regulated, being 6.42-fold and 1.91-fold to the control group, respectively, while the activities of serine protease, trypsin and chymotrypsin were inhibited. After RNA interference interfered with MsKaSPI for 6 h, the expression decreased by 73.44%, the corresponding content of MsKaSPI protein decreased by 55.66% after 12 h, and the activities of serine protease and trypsin were significantly enhanced. Meanwhile, both the larval and pupal stages of M. separata were prolonged, the weights were reduced and the number of eggs per female decreased by 181. Beauveria bassiana infection also increased the mortality of MsKaSPI-silenced M. separata by 18.96%. These prove MsKaSPI can not only result in slow growth and low fecundity of M. separata by regulating the activity of related protease, but also participate in the resistance to pathogenic fungi by regulating the serine protease inhibitor content and the activities of related serine protease.