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Fire is a material and social process that is different in different periods and places. This article examines the fires set during the largest, and last, uprising of the enslaved in Jamaica, which occurred in the island's western parishes after Christmas 1831. It argues that different sorts of fire were central to processes of production and everyday life under plantation slavery, and examines what the burnings of 1831–32 reveal about the fight against enslavement in the early nineteenth century. A close reading of the records of the trials that followed the uprising details the methods used to burn plantations; the decisions over what to burn and what to save; and the contested social and political relations involved in encouraging or extinguishing the flames. This demonstrates that fire was a material means of creative destruction for the rebels that turned the everyday practices of commodity production and coerced social reproduction against the plantation infrastructure; that destroying buildings by fire both denied and made claims on the land, and sought to remake the Jamaican landscape for other forms of inhabitation; and that the collectivities forged through fire were inevitably shaped by both shared endeavors and tensions within and between groups of plantation inhabitants facing an uncertain future. Overall, it seeks to understand the use of fire in the 1831–32 uprising to fight for freedom as part of a “politics of habitation.”
As a required sample preparation method for 14C graphite, the Zn-Fe reduction method has been widely used in various laboratories. However, there is still insufficient research to improve the efficiency of graphite synthesis, reduce modern carbon contamination, and test other condition methodologies at Guangxi Normal University (GXNU). In this work, the experimental parameters, such as the reduction temperature, reaction time, reagent dose, Fe powder pretreatment, and other factors, in the Zn-Fe flame sealing reduction method for 14C graphite samples were explored and determined. The background induced by the sample preparation process was (2.06 ± 0.55) × 10–15, while the 12C– beam current were better than 40μA. The results provide essential instructions for preparing 14C graphite of ∼1 mg at the GXNU lab and technical support for the development of 14C dating and tracing, contributing to biology and environmental science.
Omobranchus sewalli is a native Indo-Pacific blenniid recently introduced and established along the Brazilian coast. The putative introduction was through ballast water and/or ship hull biofouling. Herein, we report the presence of the species for the first time inside of the Paranaguá Estuarine Complex (PEC) which is recognized as a RAMSAR site and listed as a Wetland of International Importance. The mature specimens of O. sewalli were found in intertidal and shallow subtidal waters in the mixture zone in the estuary, suggesting the establishment of the population. The presence of port terminals in this area indicates that O. sewalli colonize PEC using ship hull fouling or larval dispersal from the shallow inner shelf.
Although the Lower Kasai was identified by Jan Vansina as a likely center for highly complex societies, he failed to recognize that sixteenth-century sources had mentioned the Empire of Mwene Muji as a large polity in that region. Studying the well known and recently discovered literature on West Central Africa, as well as a critical study of oral tradition, shows considerable evidence for the antiquity and existence of Mwene Muji.
A rise in the number of moral individuals in a group can hurt the morality of the group’s collective action. In this paper, we characterize strategic environments and models of morality where this is true solely because, after all, individual morals are private information.
We investigate air-entraining flows where degassing, rather than fragmentation, plays a significant role. Of interest is the power-law slope $\beta$ of the bulk bubble size distribution $N(a)$ during the air-generating period, when the total volume of bubbles is increasing. We study a canonical air-entraining flow created by strong underlying free-surface turbulence. We perform analysis using the population balance equation (PBE) and computations using direct numerical simulations (DNS) with bubble tracking. We quantify the importance of degassing by the ratio of degassing flux ($Q_D$) to entrainment flux ($Q_I$), $\mathcal {D}=Q_D/Q_I$, and the ratio of degassing rate ($\varLambda (a)$) to fragmentation rate ($\varOmega (a)$) for a bubble of radius $a$, $\varLambda (a)/\varOmega (a)$. For a broad range of large Froude numbers ${{Fr}}=U/\sqrt {L g}$, DNS give $\mathcal {D}=\operatorname {O}(1)$ (independent of ${{Fr}}$), showing that degassing is relevant, and $\varLambda (a) \gg \varOmega (a)$, showing that the bubble population is degassing-dominated. In contrast to fragmentation-dominated populations, such as those due to wave breaking, where $\beta =-10/3$, degassing-dominated populations have qualitatively different $N(a)$ during air entrainment. Analysis using the PBE shows that degassing-dominated $\beta$ is a function of $\varLambda (a)$, which has a turbulence-driven regime ($a< a_\varLambda$) and a buoyancy-driven regime ($a>a_\varLambda$). Here, $a_\varLambda$ is the bubble radius where terminal buoyant rise velocity equals $u_{rms}$. Consequently, $N(a)$ exhibits a split power with $\beta (a< a_\varLambda )=-4.\bar {3}$ and $\beta (a>a_\varLambda )=-5.8\bar {3}$ for moderate bubble Reynolds numbers ${{Re}}_b$. For large ${{Re}}_b$, $\beta (a>a_\varLambda )=-4.8\bar {3}$. The DNS strongly confirm these findings for moderate ${{Re}}_b$. By identifying and describing degassing-dominated bubble populations, this work contributes to the understanding and interpretation of broad types of air-entraining problems where degassing plays a relevant role.
The period 1974–1999 were transition years for government school systems in Australia and New South Wales (NSW), where government agencies issued numerous policies and documents to influence and manage education and resultant classroom pedagogy. During those years, many music syllabi were produced for enactment in NSW, placing multiple demands on teacher accountability. This paper forms part of a larger study involving three generations of music teachers representing different career stages and experiences and presents the voices of the group of experienced music teachers (EMTs), exploring the impact of syllabus change, teacher identity, pedagogical skills, and eventual flourishing as confident teachers.
Given a family of graphs $\mathcal{F}$ and an integer $r$, we say that a graph is $r$-Ramsey for $\mathcal{F}$ if any $r$-colouring of its edges admits a monochromatic copy of a graph from $\mathcal{F}$. The threshold for the classic Ramsey property, where $\mathcal{F}$ consists of one graph, in the binomial random graph was located in the celebrated work of Rödl and Ruciński.
In this paper, we offer a twofold generalisation to the Rödl–Ruciński theorem. First, we show that the list-colouring version of the property has the same threshold. Second, we extend this result to finite families $\mathcal{F}$, where the threshold statements might also diverge. This also confirms further special cases of the Kohayakawa–Kreuter conjecture. Along the way, we supply a short(-ish), self-contained proof of the $0$-statement of the Rödl–Ruciński theorem.
Childhood maltreatment (CM) deeply impacts victims’ social competences. The aim of the present study was to investigate the effect that CM duration exerts on victims’ affective and social development testing three different impact trajectories (i.e., linear, logarithmic and quadratic) and its physiological (facial mimicry and autonomic regulation of the heart) and behavioral (percentage of anger recognition false alarm) markers. In a cross-sectional design, 73 Sierra Leonean youths (all males, 5–17 years old) were enrolled in the study. Of those, 36 were homeless all abandoned at the age of 4 and exposed to CM, whereas 37 were controls. Only physiological markers of affective development were influenced by CM duration. A quadratic relation between the autonomic regulation recorded at rest and CM duration was found, indicating initial physiological compensation followed by progressive autonomic withdrawal. Furthermore, CM duration was associated to a specific linear decrease of facial mimicry and vagal regulation in response to angry and sad facial expressions whereas no influences were detected for happy and fearful faces. The results of the present study provide insightful clues on victims’ natural patterns of resilience, deterioration, and chronicity, allowing a deeper comprehension of the developmental pathways through which early life adversities place youths on a track of lifelong health disparities.
Calls for the restitution and repatriation of cultural objects continue to escalate. High-profile cases such as the Parthenon Frieze and the Benin Bronzes dominate international news cycles and provoke fierce debate; however, less attention has been paid to items that are quietly returned and to the potential positive outcomes for the institutions on both sides. This article discusses three Southeast Asian case studies to address this lacuna and urges institutions to become more proactive in their engagement with restitution and repatriation claims.
Pinyon–juniper woodlands are dry ecosystems defined by the presence of juniper (Juniperus spp.) and pinyon pine (Pinus spp.), which stretch over 400 000 km2 across 10 US states. Certain areas have become unnaturally dense and have moved into former shrub and grasslands, while others have experienced widespread mortality. To properly manage these woodlands, sites must be evaluated individually and decisions made based on scientific information that is often not available. Many species utilize pinyon–juniper woodlands, including the pinyon jay (Gymnorhinus cyanocephalus), named for its mutualism with pinyon pine, whose population has declined by c. 2.2% per year from 1966 to 2022, an overall decrease of c. 71%. To increase the likelihood of further research progress, we propose a tool to model the distribution of pinyon pine at a finer scale than current woodland classification tools in the northern US Great Basin: a random forest model using geographical, ecological and climate variables. Our results achieved an accuracy of 93.94%, indicating high predictive power to identify locations of pinyon pine in north-eastern Nevada, the south-eastern corner of Oregon and southern Idaho. These findings can inform managers and planners researching pinyon pine, pinyon–juniper woodlands and potentially the pinyon jay.
There is a need for new imaginaries of care and social health for people living with dementia at home. Day programmes are one ‘care in the community’ solution that requires further theorisation to ensure that its empirical base can usefully guide policy. In this paper we contribute to theorising day programmes through an ethnographic case study of one woman living with dementia at home using a day programme. We collected data through observations, interviews and artefacts. We observed Peg, whose case story is central in this paper, over 9 months for a total of 61 hours at the day programme, as well as during 16 hours of observation at her home and 2 community outings. We use a material semiotic approach to thinking about the day programme as a health ‘technology in practice’ to challenge the taken-for-granted ideas of day programmes as neutral, stable, bounded spaces. Peg’s case story is illustrative of how a day programme and its scripts come into relation with an arrangement of family care and life at home with dementia. At times the configuration of this arrangement works to provide a sort of stabilising distribution of care and space to allow Peg and her family to go on in the day-to-day life with dementia. At other times the arrangement may create limits to the care made possible. We argue that how we conceptualise and study day programmes and their relations to home and the broader care infrastructure affects the possibilities of care they can enact.
We obtain a new interpretation of the cohomological Hall algebra $\mathcal {H}_Q$ of a symmetric quiver Q in the context of the theory of vertex algebras. Namely, we show that the graded dual of $\mathcal {H}_Q$ is naturally identified with the underlying vector space of the principal free vertex algebra associated to the Euler form of Q. Properties of that vertex algebra are shown to account for the key results about $\mathcal {H}_Q$. In particular, it has a natural structure of a vertex bialgebra, leading to a new interpretation of the product of $\mathcal {H}_Q$. Moreover, it is isomorphic to the universal enveloping vertex algebra of a certain vertex Lie algebra, which leads to a new interpretation of Donaldson–Thomas invariants of Q (and, in particular, re-proves their positivity). Finally, it is possible to use that vertex algebra to give a new interpretation of CoHA modules made of cohomologies of non-commutative Hilbert schemes.
We use three-dimensional direct numerical simulations of homogeneous isotropic turbulence in a cubic domain to investigate the dynamics of heavy, chiral, finite-size inertial particles and their effects on the flow. Using an immersed-boundary method and a complex collision model, four-way coupled simulations have been performed, and the effects of particle-to-fluid density ratio, turbulence strength and particle volume fraction have been analysed. We find that freely falling particles on the one hand add energy to the turbulent flow but, on the other hand, they also enhance the flow dissipation: depending on the combination of flow parameters, the former or the latter mechanism prevails, thus yielding enhanced or weakened turbulence. Furthermore, particle chirality entails a preferential angular velocity which induces a net vorticity in the fluid phase. As turbulence strengthens, the energy introduced by the falling particles becomes less relevant and stronger velocity fluctuations alter the solid phase dynamics, making the effect of chirality irrelevant for the large-scale features of the flow. Moreover, comparing the time history of collision events for chiral particles and spheres (at the same volume fraction) suggests that the former tend to entangle, in contrast to the latter which rebound impulsively.
The importance of habitat-forming species, particularly cold-water corals like Dendrophyllia ramea, cannot be overstated as they provide crucial physical structures that offer shelter, food, and breeding habitat for a range of other species. We studied the spatial distribution and abundance of D. ramea, its associated species and the impact of human activities in a population of the Herradura, Granada in the western Mediterranean. Video transects were conducted at different depths, and epibiont samples were collected to describe the coral assemblage and the diversity of associated organisms. Dendrophyllia ramea presented high abundances at an unusually shallow depth in the Mediterranean, ranging from 30 to 48 m, despite typically being found between 50 and 500 m, with recordings indicating occurrences as deep as 1000 m, and hosting a high number of epibionts and macro-benthic organisms associated with coral reefs. Bryozoans showed a close relationship with D. ramea as they are important components of both the reef and the epibiont community. This study identified 63 new species and 15 new genera associated with cold-water corals. This study showed the importance of D. ramea as a nursery site, even for other habitat-forming species. The major threat to this community is human activity (fishing, littering and free anchoring), with the most abundant types of waste being rubber, glass/ceramics, and plastic polymers, and many fishing lines and nets damaging the corals. Overall, this study emphasises the urgent need to protect cold-water corals and their associated species and reduce the impact of human activities on marine ecosystems.
We characterize the fractional Dehn twist coefficient (FDTC) on the n-stranded braid group as the unique homogeneous quasimorphism to $\mathbb {R}$ of defect at most 1 that equals 1 on the positive full twist and vanishes on the $(n-1)$-stranded braid subgroup. In a different direction, we establish that the slice-Bennequin inequality holds with the FDTC in place of the writhe. In other words, we establish an affine linear lower bound for the smooth slice genus of the closure of a braid in terms of the braid’s FDTC. We also discuss connections between these two seemingly unrelated results. In the appendix, we provide a unifying framework for the slice-Bennequin inequality and its counterpart for the FDTC.