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Arsenic is a toxic metalloid with differential biological effects, depending on speciation and concentration. Trivalent arsenic (arsenite, AsIII) is more toxic at lower concentrations than the pentavalent form (arsenate, AsV). In E. coli, the proteins encoded by the arsRBC operon are the major arsenic detoxification mechanism. Our previous transcriptional analyses indicate broad changes in metal uptake and regulation upon arsenic exposure. Currently, it is not known how arsenic exposure impacts the cellular distribution of other metals. This study examines the metalloproteome of E. coli strains with and without the arsRBC operon in response to sublethal doses of AsIII and AsV. Size exclusion chromatography coupled with inductively coupled plasma mass spectrometry (SEC-ICPMS) was used to investigate the distribution of five metals (56Fe, 24Mg, 66Zn, 75As, and 63Cu) in proteins and protein complexes under native conditions. Parallel analysis by SEC-UV-Vis spectroscopy monitored the presence of protein cofactors. Together, these data reveal global changes in the metalloproteome, proteome, protein cofactors, and soluble intracellular metal pools in response to arsenic stress in E. coli. This work brings to light one outcome of metal exposure and suggests that metal toxicity on the cellular level arises from direct and indirect effects. 

In April of 2019, the Rockefeller Foundation's ‘100 Resilient Cities’ (100RC) programme abruptly shuttered, surprising programme proponents and critics alike. In this paper, we explore why this happened, why some styles of geographic critique could not anticipate 100RC’s closure, and what this inability means for dominant strands of critical geographic analysis. To answer these questions, we bring literature on the biopolitics of resilience, technopolitics and Black geographies to bear on the case of Greater Miami resilience planning. We argue that answers to these questions revolve around the designerly roots of resilience thinking, whose distinct intellectual lineage conventional critical approaches have struggled to pick up on. We show how, on the one hand, design practices of synthesis in Greater Miami attempted to frame and instrumentalise Black histories of and experiences with racial and environmental violence as bounded knowledge that could improve the functioning of complex systems. On the other hand, synthesis created overflowings: opaque knowledges and experiences that resist the framing process and continue to mediate political battles over what resilience in Greater Miami practically becomes. Based on the case, we propose that an inductive style of critique that traces processes of framing and overflowing can help advance critical geographic analysis. As we illustrate in the paper, this mode of critique pays specific attention to the opaque, historically and contextually specific knowledges and experiences that refuse to be framed or synthesised, and work to counter-frame dominant conceptions of resilience—critical and conventional alike. 

In recent years, credit rating agencies have begun to incorporate a municipality's resilience and vulnerability to climate change into their US municipal bond rating methods. Drawing on the case of Greater Miami resilience planning and Science and Technology Studies-inspired work on inscriptive devices, I investigate how this incorporation practically happens, and how it shapes the ways that Greater Miami governments attempt to govern climate risk through resilience investments. What “counts” as resilience there, I suggest, is increasingly an effect of the observational practices of rating agencies. However, the still-emergent status of resilience as an object of knowledge among rating agencies and Greater Miami governments means that resilience retains a degree of plasticity, allowing government officials and residents alike to mobilize the term for different purposes and toward different ends. In tracing the emergent relations between rating agency practice on climate risk and local government resilience investments, the paper makes two contributions to scholarship in economic and urban geography. First, it illuminates the ways that extra-local practices of expert valuation shape the local construction of environmental fixes. Second, it offers insights into how one of the key actors of the 2007–2008 financial crisis is beginning to lay the epistemic groundwork for future economic crises and inequalities in and between cities, this time as they relate to climate change impacts and a city's supposed resilience and vulnerability to them.