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Extracting blood, flies, and ideas:David and Mary Bruce, vernacular experts, and <i>unakane </i>in rural Zululand c. 1880s-1900s
No full textIn the 1890s, one of the most important scientific investigations in the early history of tropical medicine took place in rural Zululand, Colony of Natal. Since 1891, Zulu farmers’ cattle had been plagued by a deadly disease called unakane (livestock trypanosomiasis). Its cause was a subject of controversy: some blamed “big game”; others pointed at the tsetse fly, vegetation, or malaria. In 1894, the colonial government commissioned David Bruce, a Scottish-Australian surgeon-major who worked closely with his wife, Mary Bruce, to investigate. This chapter argues that the rural environment in which David Bruce was immersed was essential to his work: Zulu and settler farmers provided epidemiological theories, experimental animals, and manual labor. However, despite making major strides in the bacteriology of unakane, from which Bruce built an illustrious scientific career, his work offered almost no relief for the region, while the scientific contributions provided by local farmers were racialized and eventually forgotten
Room temperature phosphorescence from a benzothiophene-based N–B–N multi-resonance core
No full textWe report a design strategy that enables room temperature phosphorescence from an N–B–N type heterocycle, reminiscent of a multi-resonance thermally activated delayed fluorescence (MR-TADF) compound, by disturbing the alternating frontier molecular orbital distribution pattern through five-membered ring fusion with the boron atom. The 2 wt% doped film in mCP host showed a long phosphorescence lifetime of 51.5 ms at 571 nm at room temperature, with an afterglow visible for up to 1 s
Donor-substituted C(sp<sup>3</sup>)-bridged phosphorus-heterotriangulenes as blue thermally activated delayed fluorescence emitters
No full textThe selective threefold para-functionalization of the dimethylmethylene-bridged phosphorus-centered heterotriangulene is achieved via an iridium-catalyzed borylation. Conversion of the borylated compound to the corresponding bromo derivative, followed by a Buchwald–Hartwig cross-coupling with aromatic amines, affords a series of donor-acceptor fluorophores in which the central phosphoryl moiety acts as a moderate electron acceptor. The compounds exhibit an intense blue photoluminescence, which is characterized by comprehensive spectroscopic studies both in solution and in thin films, supported by density functional theory calculations, as thermally activated delayed fluorescence (TADF). Especially, the carbazole-substituted compounds show considerably narrower emission bands compared to previously reported triphenylphosphine oxide-derived systems. These findings highlight the beneficial effect of the phosphorus-centered heterotriangulene on the photophysical characteristics due to its increased rigidity imparted by the C(sp3)-based bridging moieties
Perceived gender equitable norms and previous tuberculosis testing in Malawi:a secondary analysis of a cluster-based prevalence survey
No full textSubstantial evidence demonstrates that men have a higher prevalence of tuberculosis (TB) and decreased use of TB services compared to women. Gender roles and norms contribute to these disparities by influencing social and structural determinants, as well as individual behaviours. In this analysis, we investigated attitudes towards gender equitable norms and TB testing behaviours amongst Malawian men and women participating in a prevalence survey conducted before a community-based TB active case finding trial in Blantyre. Attitudes towards equitable gender norms were captured through a modified version of the Gender Equitable Men Scale (GEMS). Gender inequitable views were prevalent among both men (56.1%) and women (55.8%). The association between a composite GEMS score and TB testing history was modelled using logistic regression, accounting for various sociodemographic covariates (age, sex, wealth quantile, education, and HIV status) (OR = 1.12, 95% CI: 0.88-1.42, p = 0.373). Bivariate analysis demonstrated no notable confounding by any covariates and no strong effect modification. While GEMS score had no association with TB testing history among women, men with higher GEMS scores (less gender-equitable views) were more likely to have been tested for TB across age groups. These findings provide a basis for future investigation into the patterns and motives TB behaviours, particularly in older men. Tailored public health strategies may then be implemented to address this important population
Dynamic effects of industrial policies amidst geoeconomic tensions
No full textAmid escalating geoeconomic tensions, industrial policy has reemerged as a central instrument of government strategy. This policy brief analyses its dynamic and welfare implications within an open-economy framework that incorporates trade and offshoring. Although short-term gains may seem appealing, they often fail to compensate for long-term losses, as firm creation is both slow and costly. If policymakers focus excessively on immediate outcomes, their choices may yield temporary welfare or wage‑equality improvements at the expense of sustained long‑run welfare
EldersOnline: an inclusive platform that leverages intergenerational learning to improve the digital literacy and social connectedness of older adults
No full textAs technology continues to permeate most aspects of our lives, many older adults face the need to improve their digital skills to avoid social isolation and exclusion from essential services. With the global older adult population projected to reach 16% by 2050, there has been a renewed urgency to address this growing digital divide. However, many existing digital literacy initiatives are often inaccessible or not optimised for touchscreen devices such as tablets, which have risen in popularity among older users. Moreover, the assistance provided by their support networks often serves as a temporary fix until a new issue arises, leading to a cycle of dependency. This pilot study aims to explore how older adults’ digital literacy and social connectedness can be improved by leveraging intergenerational exchanges. It offers insights into the experiences of older adults with technology, how younger people in their lives assist them, and the means by which both groups stay connected. As part of a user-centred design process, we conducted small but in-depth user studies with older adults, along with an online survey targeting younger individuals. Our findings, combined with research into accessible UI/UX design, led to the development of EldersOnline, an age-friendly platform that fosters personalised learning through intergenerational exchanges. While participants in our user studies responded positively to the platform, further research is needed to adapt these solutions to other aspects of older adults’ lives and to account for cultural differences. Such approaches could help bridge the global digital divide and encourage healthy ageing among older adults
Transient protostellar cores in high mass star forming regions revealed by time-resolved synthetic imaging of dust emission
No full textThe connection between dense gas cores and their infant protostars is key to understanding how stars form in molecular clouds. In this paper we investigate the properties, persistence, and protostellar content of cores that would be identified by a dendrogram analysis of 1.3 mm ALMA images. We use a time series of synthetic images produced by post-processing a simulation of star formation in a massive globally collapsing clump, with polaris to calculate dust radiative transfer and casa to generate synthetic ALMA data. Identifying sinks in the simulation with protostars, we find that most dendrogram-identified cores do not contain any protostars, with many cores being transient features associated with clumpy flow along feeder filaments. Cores with protostars generally host ≤3, and protostellar mass is not strongly correlated with the mass of the parent cores due to their transience and shifting boundaries. Calculating observationally relevant intensity-weighted average temperatures for all cores, we find that even at early times the core temperature distribution spans tens of Kelvin, and its width increases with time. The 1.3 mm peak and integrated intensity of the brightest mm core do not increase monotonically as the most massive associated protostar grows, indicating it cannot be assumed that brighter mm sources host more massive protostars. Leveraging the time domain, we test observational properties that have been proposed as potential evolutionary indicators and find that only the total 1.3 mm flux density of the region, the total 1.3 mm flux density in cores, and the number of cores show strong, statistically significant correlation with time
The role of mergers and rejuvenation in the buildup of the quiescent population at cosmic noon
No full textWe investigate the quenching of galaxies using a mock observational light-cone generated from the Semi-Analytic Model (SAM)L-Galaxies, closely matched to observations from the UKIDSS Ultra Deep Survey (UDS). The sample is used to study merging,rejuvenation, and visibility times for star-forming, quiescent, and post-starburst (PSB) galaxies, to assess the impact on the buildup of the passive galaxy mass functions. We find, for example, that a typical PSB (M∗ ∼ 1010 M☉) at z ≈ 1 has a 15 per centlikelihood of merging and around a 25 per cent likelihood of rejuvenating within 1 Gyr of being identified. Applying these ratesand time-scales to the observational data, we estimate the fraction of quiescent galaxies that passed through a PSB phase. Wefind that 18–28 per cent of the build-up in the massive end (M∗ > 1010 M☉) of the passive mass function at 1 < z < 2 can beexplained by PSBs, with the contribution declining to ∼ 5 per cent by z ≃ 0.5. Accounting for mergers and rejuvenation reducesthe inferred PSB contribution by approximately a factor of two. At lower stellar masses (M∗ < 1010 M☉), rapid quenchingthrough a PSB phase explains a significantly larger fraction of the growth in the passive mass function. With a visibility timeof ∼0.75 Gyr, we find that around 60–80 per cent of low-mass passive galaxies underwent a PSB phase. Our findings providefurther evidence that low- and high-mass galaxies follow different quenching pathways
Memory trajectories by migration status and gender:a life-course intersectional perspective
No full textThis study explores the relationships between migration, gender, and memory trajectories over the life–course within an intersectional framework. Memory is an important dimension of cognitive decline, a critical concern in aging populations, and varies significantly across different demographic groups. In this paper we address the understudied influence that the intersection of gender and migration status has on memory trajectories and evaluate the role of age at migration. Using random-effects growth curve models, our findings reveal persistent memory disparities by migration status, particularly in early older age, though differentials by migration status generally reduce after age 70. Immigrants, overall, exhibit lower baseline memory functioning levels and steeper declines. Contrary to expectations, immigrant women are not uniquely vulnerable; instead, gender differences persist across groups, with men generally faring worse. Later age at migration predicts poorer memory performance, though a late-life advantage emerges for men who migrated at ages 6–17 warranting further investigation. These results underscore the importance of considering baseline levels, longitudinal patterns, and intersectional factors in cognitive aging research by migration status
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