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Microbial associates of the elm leaf beetle : uncovering the absence of resident bacteria and the influence of fungi on insect performance
Get PDFThis study was supported by the German Research Foundation (Deutsche Forschungsgemeinschaft) (Collaborative Research Centre 973, project B1; http://www.sfb973.de/).Microbial symbionts play crucial roles in the biology of many insects. While bacteria have been the primary focus of research on insect-microbe symbiosis, recent studies suggest that fungal symbionts may be just as important. The elm leaf beetle (ELB, Xanthogaleruca luteola) is a serious pest species of field elm (Ulmus minor). Using culture-dependent and independent methods, we investigated the abundance and species richness of bacteria and fungi throughout various ELB life stages and generations, while concurrently analyzing microbial communities on elm leaves. No persistent bacterial community was found to be associated with the ELB or elm leaves. By contrast, fungi were persistently present in the beetle's feeding life stages and on elm leaves. Fungal community sequencing revealed a predominance of the genera Penicillium and Aspergillus in insects and on leaves. Culture-dependent surveys showed a high prevalence of two fungal colony morphotypes closely related to Penicillium lanosocoeruleum and Aspergillus flavus. Among these, the Penicillium morphotype was significantly more abundant on feeding-damaged compared with intact leaves, suggesting that the fungus thrives in the presence of the ELB. We assessed whether the detected prevalent fungal morphotypes influenced ELB's performance by rearing insects on (i) surface-sterilized leaves, (ii) leaves inoculated with Penicillium spores, and (iii) leaves inoculated with Aspergillus spores. Insects feeding on Penicillium-inoculated leaves gained more biomass and tended to lay larger egg clutches than those consuming surface-sterilized leaves or Aspergillus-inoculated leaves. Our results demonstrate that the ELB does not harbor resident bacteria and that it might benefit from associating with Penicillium fungi.IMPORTANCEOur study provides insights into the still understudied role of microbial symbionts in the biology of the elm leaf beetle (ELB), a major pest of elms. Contrary to expectations, we found no persistent bacterial symbionts associated with the ELB or elm leaves. Our research thus contributes to the growing body of knowledge that not all insects rely on bacterial symbionts. While no persistent bacterial symbionts were detectable in the ELB and elm leaf samples, our analyses revealed the persistent presence of fungi, particularly Penicillium and Aspergillus on both elm leaves and in the feeding ELB stages. Moreover, when ELB were fed with fungus-treated elm leaves, we detected a potentially beneficial effect of Penicillium on the ELB's development and fecundity. Our results highlight the significance of fungal symbionts in the biology of this insect.Peer reviewe
Wireless magnetoelectrically powered organic light-emitting diodes
Get PDFThis work was supported by a scholarship to J.F.B. donated by Beverly and Frank MacInnis to the University of St Andrews, the European Union Horizon 2020 research and innovation program under Marie Skłodowska-Curie grant agreement no. 101023743 (PolDev to A.M.), The Leverhulme Trust (RPG-2017-231), the Alexander von Humboldt Foundation (Humboldt Professorship to M.C.G.), the DFG-funded Research Training Group “Template-Designed Organic Electronics (TIDE)” (RTG2591), and the EPSRC NSF-CBET lead agency agreement (EP/R010595/1, 1706207).Compact wireless light sources are a fundamental building block for applications ranging from wireless displays to optical implants. However, their realization remains challenging because of constraints in miniaturization and the integration of power harvesting and light-emission technologies. Here, we introduce a strategy for a compact wirelessly powered light-source that consists of a magnetoelectric transducer serving as power source and substrate and an antiparallel pair of custom-designed organic light-emitting diodes. The devices operate at low-frequency ac magnetic fields (~100 kHz), which has the added benefit of allowing operation multiple centimeters deep inside watery environments. By tuning the device resonance frequency, it is possible to separately address multiple devices, e.g., to produce light of distinct colors, to address individual display pixels, or for clustered operation. By simultaneously offering small size, individual addressing, and compatibility with challenging environments, our devices pave the way for a multitude of applications in wireless displays, deep tissue treatment, sensing, and imaging.Peer reviewe
The link between intimate partner violence and spousal resource inequality in lower- and middle-income countries
Get PDFObjective There is an increasing need to understand how differential levels of resource inequality between spouses are associated with women's experience of intimate partner violence (IPV) in lower- and middle-income countries across four regions. This study aims to focus on four areas of relative power and resources between couples in a partnership: employment, job skills, earnings, and household making-decision across four lower- and middle-income regions. Method Data on 150,623 women was drawn from the most recent, harmonized Demographic and Health Survey (DHS) for 24 countries in West-Central Africa (WCA), East-Southern Africa (ESA), Middle East and North Africa (MENA), and South Asia (SA). Leveraging an event history framework, we fitted mixture cure models to illuminate both the likelihood of never experiencing IPV and the onset of IPV among women in their first union across the four regions. Results We found that women who are not in the labor market are less likely to experience violence compared to those who are in all places except MENA. Among couples in which both partners are in the labor market, women with lower job skills than their partner are less likely to experience violence. Inequality in earnings is associated with the onset of intimate partner violence in ESA and SA. Similarly, inequality in household decision-making is associated with the onset of the first spousal violence but only in ESA, MENA, and SA. Conclusion This study found vast heterogeneity in the different measures of spousal resource inequality and women's experience of IPV across LMIC settings. This underscores the imperative for interventions focused on enhancing women's economic outcomes to consider and confront the contextual norms associated with women's economic empowerment, in order to mitigate unintended adverse consequences.Peer reviewe
Question-relative knowledge for minimally rational agents
Get PDFFunding: Fundação para a Ciência e a Tecnologia.Agents know some but not all logical consequences of what they know. Agents seem to be neither logically omniscient nor logically incompetent. Yet finding an intermediate standard of minimal rationality has proven difficult. In this paper, I take suggestions found in the literature [Lewis, D. 1988. Relevant Implication. Theoria 54 (3): 161174. https://doi.org/10.1111/theo.1988.54.issue-3; Hawke, P., A. Özgün, and F. Berto. 2020. The Fundamental Problem of Logical Omniscience. Journal of Philosophical Logic 49 (4): 727766. https://doi.org/10.1007/s10992-019-09536-6; Plebani, M., and G. Spolaore. 2021. Subject Matter: A Modest Proposal. The Philosophical Quarterly 71 (3): 605622. https://doi.org/10.1093/pq/pqaa054] and join the forces of subject matter and impossible worlds approaches to devise a new solution to this quandary. I do so by combining a space of FDE worlds [Berto, F., and M. Jago. 2019. Impossible Worlds. Oxford University Press.] with a Lewisian (1988) understanding of subject matters as partitions. By doing so, I show how subject matters impose some order in the anarchic space of FDE worlds, while the worlds allow for distinctions between contents which would not otherwise be available. Combining the two approaches, then, brings us closer to the desired closure principles for knowledge of minimally rational agents.Peer reviewe
Assouad type dimensions of infinitely generated self-conformal sets
Get PDFFunding: Both authors were financially supported by a Leverhulme Trust Research Project Grant (RPG-2019-034). JMF was also supported by an EPSRC Standard Grant (EP/R015104/1) and an RSE Sabbatical Research Grant (70249). Most of this work was completed while AB was JMF’s PhD student at the University of St Andrews, but AB was also supported by an EPSRC New Investigators Award (EP/W003880/1) while a postdoc at Loughborough University.We study the dimension theory of limit sets of iterated function systems consisting of a countably infinite number of conformal contractions. Our focus is on the Assouad type dimensions, which give information about the local structure of sets. Under natural separation conditions, we prove a formula for the Assouad dimension and prove sharp bounds for the Assouad spectrum in terms of the Hausdorff dimension of the limit set and dimensions of the set of fixed points of the contractions. The Assouad spectra of the family of examples which we use to show that the bounds are sharp display interesting behaviour, such as having two phase transitions. Our results apply in particular to sets of real or complex numbers which have continued fraction expansions with restricted entries, and to certain parabolic attractors.Peer reviewe
Neural network classification of eigenmodes in the magnetohydrodynamic spectroscopy code Legolas
Get PDFJDJ was supported by funding from the European Research Council (ERC) under the European Unions Horizon 2020 research and innovation programme, Grant agreement No. 833251 PROMINENT ERC-ADG 2018.A neural network is employed to address a non-binary classification problem of plasma instabilities in astrophysical jets, calculated with the Legolas code. The trained models exhibit reliable performance in the identification of the two instability types supported by these jets. We also discuss the generation of artificial data and refinement of predictions in general eigenfunction classification problems.Peer reviewe
Global modern slavery and sustainable development goals : does institutional environment quality matter?
Get PDFModern slavery is a persistent human tragedy and a growing organisational risk. The United Nations' sustainable development goals highlight the significance of governments in shaping firms' sustainability agenda and combating modern slavery. However, little is known about the effects of the institutional environment on modern slavery risk. This study, therefore, investigates the crucial policy question of whether the quality of the institutional environment has any effect on modern slavery and whether sustainable human development reinforces this relationship. Using data from 167 countries, we find that institutional environment quality is negatively associated with the prevalence of and vulnerability to modern slavery and positively associated with its modern slavery risk mitigation. Our results suggest that democratically elected governments operating in politically stable societies with higher quality of voice and accountability, higher levels of control of corruption, and stricter rule of law are more accountable and responsive to modern slavery risks. We also find that sustainable human development (HDI) has a moderating effect on the relationship between institutional environment quality and modern slavery, and this effect is mainly noticeable in low HDI countries. These results imply that governance reforms alone might not yield the desired effects for all countries and, hence, have significant implications for policymakers, companies, and societal stakeholders.Peer reviewe
How genomics can help biodiversity conservation
Get PDFThe availability of public genomic resources can greatly assist biodiversity assessment, conservation, and restoration efforts by providing evidence for scientifically informed management decisions. Here we survey the main approaches and applications in biodiversity and conservation genomics, considering practical factors, such as cost, time, prerequisite skills, and current shortcomings of applications. Most approaches perform best in combination with reference genomes from the target species or closely related species. We review case studies to illustrate how reference genomes can facilitate biodiversity research and conservation across the tree of life. We conclude that the time is ripe to view reference genomes as fundamental resources and to integrate their use as a best practice in conservation genomics.Peer reviewe
John, divine locality and the Book of Revelation
Get PDFThis thesis argues that John, the author of Revelation, depended upon two traditions or cultural models for the development of his theology: the corporeality of God and the heavenly temple. 'Cultural model' is a term used in cognitive anthropology to refer to conceptual constructs shared amongst persons in a given culture, which helps those persons sense-make and behave in their world. John used the cultural models of divine corporeality and the heavenly temple to construct a unique cosmology and theology in his apocalypse. Moreover, these cultural models and his resultant theological system helped John answer critical questions facing him at the end of the first century: Where is the Messiah, and why is he gone? For John, Jesus was absent in his world because he was completing necessary sacrificial and sacerdotal ministries at the heavenly temple so that the world could be purged of its impurities, allowing the Lord God to dwell physically with his people on earth
UAV approaches for improved mapping of vegetation cover and estimation of carbon storage of small saltmarshes examples from Loch Fleet, northeast Scotland
Get PDFSaltmarsh environments are recognised as key components of many biophysical and biochemical processes at the local and global scale. Accurately mapping these environments, and understanding how they are changing over time, is crucial for better understanding these systems. However, traditional surveying techniques are time-consuming and are inadequate for understanding how these dynamic systems may be changing temporally and spatially. The development of Uncrewed Aerial Vehicle (UAV) technology presents an opportunity for efficiently mapping saltmarsh extent. Here we develop a methodology which combines field vegetation surveys with multispectral UAV data collected at two scales to estimate saltmarsh area and organic carbon storage at three saltmarshes in Loch Fleet (Scotland). We find that the Normalised Difference Vegetation Index (NDVI) values for surveyed saltmarsh vegetation communities, in combination with local tidal data, can be used to reliably estimate saltmarsh area. Using these area estimates, together with known plant community and soil organic carbon relationships, saltmarsh soil organic carbon storage is modelled. Based on our most reliable UAV-derived saltmarsh area estimates, we find that organic carbon storage is 15-20% lower than previous area estimates would indicate. The methodology presented here potentially provides a cheap, affordable, and rapid method for saltmarsh mapping which could be implemented more widely to test and refine existing estimates of saltmarsh extent and is particularly well-suited to the mapping of small areas of saltmarsh environments.Peer reviewe
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