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Abstract New tailpipe emissions standards aim to increase electric vehicle (EV) sales in the United States. Here, we analyze the associated critical mineral supply chain constraints and enumerate the climate consequences of these constraints. Our work yields five findings. First, the proposed standard necessitates replacing at least 10.21 million new internal combustion engine vehicles with EVs between 2027 and 2032. Second, based on economically viable and geologically available mineral reserves, manufacturing sufficient EVs is plausible and reduces up to 457.3 million tons of CO2e. Third, mineral production capacities in the United States and amongst allies support the deployment of 5.09 million vehicles between 2027 and 2032, well short of compliance target. Fourth, this shortfall produces at least 59.54 million tons of CO2e in lost lifecycle emissions benefits. Fifth, limited production of battery-grade graphite and cobalt may represent particularly profound constraints. Pathways that afford comparable emission reductions are subsequently explored.

ABSTRACT Although parasite entry through breaks in the skin or mucosa is one of the main routes of natural transmission of Trypanosoma cruzi, little is known about the host cell types initially invaded nor the ability of those host cells to initiate immune responses at the site of infection. To gain insights into these early events, we studied the fate of fluorescently tagged T. cruzi delivered subcutaneously in mouse footpads or ears. We demonstrate that the majority of parasites introduced into the skin initially proliferate there until 8 to 10 days postinfection, when the parasite load decreases. This decline in parasite numbers is dependent on the presence of an intact T cell compartment and on the ability of hosts to produce gamma interferon (IFN-γ). Many of the parasite-containing cells at the initial infection site display a macrophage/monocyte phenotype but with low expression of activation markers, suggesting that these cells provide an early niche for T. cruzi proliferation, rather than being active in parasite control. It is only after the first round of T. cruzi replication and release from host cells that signs of immune activation and control of parasites become apparent. The delay in the activation and failure to rapidly control parasite replication are observed even when T. cruzi-primed T cells are present, such as in chronically infected mice. This failure of a primed immune system to recognize and react prior to extensive parasite expansion at the infection site likely poses a significant challenge for the development of vaccines aiming to prevent T. cruzi infection. IMPORTANCE Trypanosoma cruzi, the parasite causing Chagas disease, usually infects through the mucosa or breaks in the skin, but little is known about the parasite's fate at the site of entry or the early events involving immune control there. Here, we track the local proliferation and subsequent dissemination of fluorescently tagged T. cruzi and the initial immune response at the point of entry. We show that T. cruzi preferentially infects innate immune cells in the skin and that the stimulation of an adaptive T cell response does not occur until after the release of parasites from this first round of infected host cells. This first immunologically “silent” proliferation occurs even in the presence of a strong immune T cell memory generated by previous infection. This capacity of T. cruzi to establish infections while avoiding initial immune recognition has important implications for the potential to develop vaccines to prevent T. cruzi infection.

Resistance to primary treatments of invasive aspergillosis is growing. Here, the authors generate a knockout library for 484 transcription factors in Aspergillus fumigatus, and show that loss of the NCT complex leads to cross-resistance to all primary and some salvage therapeutics without affecting pathogenicity.

We review the status of marine shellfish ecosystems formed primarily by bivalves in Australia, including: identifying ecosystem-forming species, assessing their historical and current extent, causes for decline and past and present management. Fourteen species of bivalves were identified as developing complex, three-dimensional reef or bed ecosystems in intertidal and subtidal areas across tropical, subtropical and temperate Australia. A dramatic decline in the extent and condition of Australia's two most common shellfish ecosystems, developed by Saccostrea glomerata and Ostrea angasi oysters, occurred during the mid-1800s to early 1900s in concurrence with extensive harvesting for food and lime production, ecosystem modification, disease outbreaks and a decline in water quality. Out of 118 historical locations containing O. angasi-developed ecosystems, only one location still contains the ecosystem whilst only six locations are known to still contain S. glomerata-developed ecosystems out of 60 historical locations. Ecosystems developed by the introduced oyster Crasostrea gigas are likely to be increasing in extent, whilst data on the remaining 11 ecosystem-forming species are limited, preventing a detailed assessment of their current ecosystem-forming status. Our analysis identifies that current knowledge on extent, physical characteristics, biodiversity and ecosystem services of Australian shellfish ecosystems is extremely limited. Despite the limited information on shellfish ecosystems, a number of restoration projects have recently been initiated across Australia and we propose a number of existing government policies and conservation mechanisms, if enacted, would readily serve to support the future conservation and recovery of Australia's shellfish ecosystems.

The potential effect of climate change on regional suitability for cocoa cultivation is a serious economic concern for West Africa—especially for Ghana and Côte d’Ivoire, whose cocoa cultivation accounts for respectively ∼19% and ∼45% of world production. Here, we present a modelling and observational study of cocoa net primary productivity (NPP) in present day and future West African climates. Our analysis uses a data assimilation technique to parameterise a process-based land-surface model. The parameterisation is based on laboratory observations of cocoa, grown under both ambient and elevated CO _2 . Present day and end of 21st century cocoa cultivation scenarios are produced by driving the parameterised land-surface model with output from a high-resolution climate model. This represents a significant advance on previous work, because unlike the CMIP5 models, the high-resolution model used in this study accurately captures the observed precipitation seasonality in the cocoa-growing regions of West Africa—a key sensitivity for perennials like cocoa. We find that temperature is projected to increase significantly and precipitation is projected to increase slightly, although not in all parts of the region of interest. We find, furthermore, that the physiological effect of higher atmospheric CO _2 concentration ameliorates the impacts of high temperature and variation in precipitation thereby reducing some of the negative impacts of climate change and maintaining NPP in West Africa, for the whole 21st Century, even under a high emissions scenario. Although NPP is an indicator of general vegetation condition, it is not equivalent to yield or bean quality. The study presented here is, nevertheless, a strong basis for further field and modelling studies of cultivation under elevated CO _2 conditions.

Recent behavioral evidence suggests that dogs, like humans and monkeys, are capable of visual face recognition. But do dogs also exhibit specialized cortical face regions similar to humans and monkeys? Using functional magnetic resonance imaging (fMRI) in six dogs trained to remain motionless during scanning without restraint or sedation, we found a region in the canine temporal lobe that responded significantly more to movies of human faces than to movies of everyday objects. Next, using a new stimulus set to investigate face selectivity in this predefined candidate dog face area, we found that this region responded similarly to images of human faces and dog faces, yet significantly more to both human and dog faces than to images of objects. Such face selectivity was not found in dog primary visual cortex. Taken together, these findings: (1) provide the first evidence for a face-selective region in the temporal cortex of dogs, which cannot be explained by simple low-level visual feature extraction; (2) reveal that neural machinery dedicated to face processing is not unique to primates; and (3) may help explain dogs’ exquisite sensitivity to human social cues.

Accelerating environmental change is perhaps the greatest challenge for natural resource management; successful strategies need to be effective for decades to come. Our objective is to identify opportunities that new environmental conditions may provide for conservation, restoration, and resource use in a globally recognized biodiversity hotspot in southwestern Australia. We describe a variety of changes to key taxonomic groups and system-scale characteristics as a consequence of environmental change (climate and land use), and outline strategies for conserving and restoring important ecological and agricultural characteristics. Opportunities for conservation and economic adaptation are substantial because of gradients in rainfall, temperature, and land use, extensive areas of remnant native vegetation, the ability to reduce and ameliorate areas affected by secondary salinization, and the existence of large national parks and an extensive network of nature reserves. Opportunities presented by the predicted environmental changes encompass agricultural as well as natural ecosystems. These may include expansion of aquaculture, transformation of agricultural systems to adapt to drier autumns and winters, and potential increases in spring and summer rain, carbon-offset plantings, and improving the network of conservation reserves. A central management dilemma is whether restoration/preservation efforts should have a commercial or biodiversity focus, and how they could be integrated. Although the grand challenge is conserving, protecting, restoring, and managing for a future environment, one that balances economic, social, and environmental values, the ultimate goal is to establish a regional culture that values the unique regional environment and balances the utilization of natural resources against protecting remaining natural ecosystems.

An examination of a few examples of aquifer-use shows the importance and fragility of groundwater, with poor management leading to over-extraction by individuals and authorities producing subsidence – sinking cities. Freshwater is one of our most precious resources and it is rapidly disappearing, leading to global drying. At the same time, the global and urban populations are increasing, with civil unrest increasing due, in part, to freshwater shortages. The increasing global population and global urbanisation are driving an increase in water use, restriction of aquifer recharge and increased aquifer pollution. It is argued that urban population growth with attendant increased water use, combined with climate change and poor management, is significant in water stress. Particular attention must be paid to the effect of rising populations on local water resources, especially groundwater, and the knock-on effect on urban sustainability.