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Money and the Making of the American Revolution
No full textAmerican money and American democracy have always been in tension, pitting political equality against economic inequality. In Money and the Making of the American Revolution, Andrew Edwards shows how this struggle emerged in America’s founding era. Everyone knows that the founders waged a revolt against taxation without representation. Edwards shows that the dispute over taxes was really a dispute over money: what it was, who could make it, and how to keep it from being used at the expense of the colonists in North America. The colonial rebels refocused their resistance on democratic, local control—defending the power they had used to make money for themselves.Edwards’s narrative spans four continents, linking the problems of money and revolt in early America to the transatlantic slave trade, the disastrous mismanagement of the East India Company in India, and violence against Native Americans. His analysis emerges from the story itself, through the lives of individuals ranging from John Blackwell, Oliver Cromwell’s one-time war treasurer, to Thomas Paine, the impassioned pamphleteer of the American Revolution. Edwards argues that as the republican vision of an agrarian, independent monetary system faded, the leaders of the Revolution tied the nation to capitalism and imperialism at its founding. The colonists may have won the battle for representation, but the money that underpinned European empire had established a stronghold in the new republic. Money and the Making of the American Revolution offers both an ambitious new interpretation of the Revolution and a fascinating story about the power of economic ideas
Bridging the gap:tackling health inequity through community engagement in medical education
No full textIntegrated population clustering and genomic epidemiology with PopPIPE
No full textGenetic distances between bacterial DNA sequences can be used to cluster populations into closely related subpopulations and as an additional source of information when detecting possible transmission events. Due to their variable gene content and order, reference-free methods offer more sensitive detection of genetic differences, especially among closely related samples found in outbreaks. However, across longer genetic distances, frequent recombination can make calculation and interpretation of these differences more challenging, requiring significant bioinformatic expertise and manual intervention during the analysis process. Here, we present a Population analysis PIPEline (PopPIPE) which combines rapid reference-free genome analysis methods to analyse bacterial genomes across these two scales, splitting whole populations into subclusters and detecting plausible transmission events within closely related clusters. We use k-mer sketching to split populations into strains, followed by split k-mer analysis and recombination removal to create alignments and subclusters within these strains. We first show that this approach creates high-quality subclusters on a population-wide dataset of Streptococcus pneumoniae. When applied to nosocomial vancomycin-resistant Enterococcus faecium samples, PopPIPE finds transmission clusters that are more epidemiologically plausible than core genome or multilocus sequence typing (MLST) approaches. Our pipeline is rapid and reproducible, creates interactive visualizations and can easily be reconfigured and re-run on new datasets. Therefore, PopPIPE provides a user-friendly pipeline for analyses spanning species-wide clustering to outbreak investigations
Sodium ion conductivities in Na<sub>2</sub>O–Sm<sub>2</sub>O<sub>3</sub>–SiO<sub>2</sub> ceramics
No full textCeramic solid electrolytes are promising candidates for advanced solid-state batteries (SSBs) owing to their good ionic conductivity, wide electrochemical stability window, excellent thermal stability and enhanced safety compared to organic liquid electrolytes. In this study, we developed a series of sodium samarium silicates via a conventional solid-state approach using NaNO3, Sm2O3, and SiO2 precursor powders. By incorporating varying amounts of NaNO3, we optimized the ionic conductivity influenced by sodium, and a higher Na content increased the ionic conductivity of silicates to an extent. Among the compositions prepared, N5Sm exhibited the lowest grain boundary resistance and achieved the highest total ionic conductivity of 1.33 × 10−3 S cm−1 at 25 °C after being sintered at 975 °C. The best ion conducting composition demonstrated an electronic conductivity of 9.47 × 10−10 S cm−1, seven orders of magnitude lower than the ionic conductivity. These silicates also showed exceptional electrochemical stability up to 9 V, making them highly suitable for advanced high-voltage sodium battery applications. These findings underscore the potential of silicate electrolytes in developing next-generation batteries
Surviving colonies of <i>Pseudomonas aeruginosa</i> isolated in vivo from infected, antibiotic-treated <i>Galleria mellonella</i> larvae acquire an antibiotic-tolerant phenotype
No full textBackground: The aim of this work was to induce the formation of antibiotic-tolerant and/or persister cells in vivo using antibiotic therapy on Galleria mellonella larvae infected with P. aeruginosa, isolate these surviving cells, and characterise their phenotype and genotype. Methods: Infected larvae were treated with effective doses of either ceftazidime or meropenem. Despite this, surviving P. aeruginosa colonies were isolated from living larvae, and antibiotic killing, fitness, virulence, antibiotic resistance and the whole genome sequence of a selection of these isolates were compared with their original parent strains. Results: The surviving isolates had an increased minimum duration to kill 99% of the population (MDK99) upon exposure to ceftazidime or meropenem and decreased growth rates in culture, but they showed no change to the MIC or virulence—consistent with an antibiotic-tolerant phenotype. Long-read genome sequencing of selected isolates revealed only one single nucleotide polymorphism (SNP) within bkdB, encoding the lipoamide acyltransferase component of the branched-chain α-keto acid dehydrogenase, present in two independent isolates. However, time-kill assays with ceftazidime of bkdB knockout strains showed no significant change in the MDK99. Concomitant with the antibiotic-tolerant phenotype, many of the isolates also had a reduced rate of killing when exposed to heat stress. Conclusions: P. aeruginosa cells that survived antibiotic therapy in vivo were found to be antibiotic-tolerant and thermotolerant but not antibiotic-resistant and had reduced growth rates under optimal conditions but unchanged virulence. In the absence of a convincing genetic explanation, the co-induction of enhanced thermotolerance with antibiotic tolerance indicated that both are conferred by a heritable phenotypic mechanism
Open-source high-resolution exoplanet atmosphere retrievals with POSEIDON
No full textHigh-resolution spectroscopy (R > 25,000) has opened new opportunities to characterize exoplanet atmospheres from the ground. By resolving individual lines in planetary emission and transmission spectra, one can sensitively probe the chemical inventory and temperature structure of exoplanets. However, a significant challenge to reliable and reproducible atmospheric inferences from high-resolution data sets has been the lack of open-source codes for high-resolution retrievals. Here, we present a unified high-resolution retrieval framework, for both emission and transmission spectroscopy, made publicly available within the open-source POSEIDON retrieval code. Our high-resolution retrieval framework is fast, accessible (no GPUs required), and well documented via Python notebooks. We validate our framework by reproducing previous emission retrievals of the hot Jupiter WASP-77Ab and transmission retrievals of the ultrahot Jupiter WASP-121b. Our results are broadly consistent with those of published works when making the same data detrending assumptions, but we demonstrate that user choices can subtly propagate into retrieved chemical abundances
A conceptual framework for measuring ecological novelty
No full textBackground: Human pressures are driving the emergence of unprecedented, ‘novel’, ecological and environmental systems. The concept of novel (eco)systems is well accepted by the scientific community, but the use and measurement of novelty has outgrown initial definitions and critiques. There are still unresolved methodological and conceptual differences in quantifying novelty that prevent a unified research approach. Framework: Here we present a conceptual framework and guidelines to unify past and future measurement of ecological novelty. Under this framework, novelty is a property of an ecological or environmental entity of interest. Novelty is quantified as the comparison between the target entity and a reference set, measured as the summary of degrees of difference across one or more dimensions. Choices in these components, particularly the reference set, can change resulting novelty measurements and inferences. Showcase: We provide a case-study to showcase our framework, measuring pre- and post-European novelty in 99 pollen assemblages in Midwest USA forests. We paired this quantitative exploration with a five-step process designed to improve the utility and outcomes of novelty analyses. Conclusions: Quantitative novelty has immense value in studies of abrupt ecological change, linking climatic and ecological change, biotic interactions and invasions, species range shifts and fundamental theories. Our framework offers a unified overview and is also primed for integration into management and restoration workflows, providing consistent and robust measurements of novelty to support decision making, priority setting and resource allocation
Adsorption pathways of boron on clay and their implications for boron cycling on land and in the ocean
No full textReversible adsorption and isotope fractionation of boron on the surface of clay minerals is a key process that impacts boron isotope cycling in porewater, rivers and the ocean. However, the differences in boron isotope fractionation factors between various clay minerals and their dependence on fluid chemistry are not well known. We performed two sets of experiments, using solutions of pure water with added boron and seawater, to explore the isotope behavior during adsorption of boron onto kaolinite, smectite and illite. We found that the amount of sorbed boron increases with ionic strength of solutions and is proportional to the cation exchange capacity of a given clay mineral. Maximum adsorption is observed in alkaline seawater, which we attribute to the efficient fixation of magnesium-borate ion pairs onto negatively charged surface sites. Isotopic fractionation is modestly different between clays and demonstrates that clay surfaces preferentially sorb borate, even when the concentration of borate in solution is low. In both pure water and seawater, adsorbed complexes retain the isotopic composition of their dissolved precursors (borate or boric acid) with minimal isotopic fractionation. In other words, isotopic composition of adsorbed boron is set by the ability of clays to adsorb boron from an already fractionated boron pool rather than specific fractionation associated with the complexation reaction. Our experimental results allow us to provide revised constraints on the adsorbed boron being transported in terrestrial fluids and the ocean
Athanor: Local search over abstract constraint specifications
No full textLocal search is a common method for solving combinatorial optimisation problems. We focus on general-purpose local search solvers that accept as input a constraint model - a declarative description of a problem consisting of a set of decision variables under a set of constraints. Existing approaches typically take as input models written in solver-independent constraint modelling languages like MiniZinc. The Athanor solver we describe herein differs in that it begins from a specification of a problem in the abstract constraint specification language Essence, which allows problems to be described without commitment to low-level modelling decisions through its support for a rich set of abstract types. The advantage of proceeding from Essence is that the structure apparent in a concise, abstract specification of a problem can be exploited to generate high quality neighbourhoods automatically, avoiding the difficult task of identifying that structure in an equivalent constraint model. Based on the twin benefits of neighbourhoods derived from high level types and the scalability derived by searching directly over those types, our empirical results demonstrate strong performance in practice relative to existing solution methods