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Frontal eddies form on the shoreward edge of boundary currents, on average at weekly intervals and can last up to several weeks. This duration allows zooplankton production and completion of the larval stage of fish but may be too ephemeral for longer food chains with planktonic predators to establish. Therefore, frontal eddies may provide a suitable offshore nursery habitat, by entraining and retaining inner‐shelf water, preconditioned with coastal plankton and ichthyoplankton, into an upwelling favorable cyclonic eddy. Here, we briefly describe the behavior of frontal eddies formed by western boundary currents in the context of the fundamental ocean triad, which incorporates three processes for the successful reproduction of fish: nutrient enrichment, food concentration, and retention of larvae. We adapt this hypothesis for frontal eddies adjacent to the substantial fisheries production of continental shelves, creating conditions for enhanced recruitment potential of larval cohorts at a finer scale than previously considered. We review the evidence and investigations of frontal eddies in their capacity to entrain coastal water, sustain the plankton community through eddy uplift and retain distinctive coastal communities of larval fish offshore until larval development is complete. The process of frontal eddy formation is complex and such habitats are irregular yet ubiquitous, which present challenges and opportunities for their study. With the advance of ocean observing systems and integration of physical and biological sampling, frontal eddies provide a novel focus for understanding fisheries production and connectivity of coastal ecosystems.

Creutzfeldt-Jakob disease is a rare and incurable form of rapidly progressive neurodegenerative disease. The disease is fatal, and most patients die within 1 year of diagnosis. Clinical features include progressive cognitive dysfunction, delusions or hallucinations, cerebellar ataxia, myoclonus, visual disturbances, extrapyramidal signs and eventually akinetic mutism. Most patients present with varied clinical presentation, hence making it difficult to diagnose at an early stage. We report five cases of sporadic Creutzfeldt-Jakob disease presenting to a Tasmanian hospital in Australia over a period of 52 months. We highlight significant clinical features in all our patients including few atypical presentations, emphasise on relevant clinical biomarkers and illustrate characteristic abnormalities on electroencephalogram and neuroimaging.

There is an ambivalence within political ecology about whether the unequal power relations that emerge from many development projects are intended or unintended. This ambivalence is a result of an empirical focus on the effects of these programs on target communities, as opposed to an empirical focus on the people who are responsible for developing those programs. Drawing on qualitative fieldwork among people tasked with designing, promoting, and enforcing sustainability standards in global agricultural supply chains, I argue that the empowerment of multinational corporations and well-funded environmental NGOs that characterizes market-oriented sustainability programs is, in fact, intentional. This intention reflects the belief among sustainability professionals that the intersection of western scientific expertise with the dynamics of “the market” is the most effective way to promote sustainability in global supply chains, and to generate global sustainability in a more general sense. Concepts like “stakeholder engagement” and a commitment to flexibility and accommodation in the development and adoption of social and environmental standards are examples of what I call euphemistic sustainability, which shifts critical attention away from a balance of power that is increasingly tilted toward private interests, even as that imbalance remains an intended outcome of non-state market-driven governance systems like ostensibly voluntary sustainability standards.

This essay advances a critique of the stakeholder concept based on the relative function of stakes and stakeholders in games of risk and reward such as roulette, cockfighting, and, if economists are right, climate negotiations. It asks what happens when corporate sustainability and other market-based “solutions” to socio-ecological crises such as climate change and mass extinction are perceived as a kind of casino. Dispossessed stakeholders become background props at sustainability conferences and other events where dramatic doom-and-gloom narratives of catastrophe serve as a way to reinforce global geographies of power and extraction. Being honest about the effects of categorizing such diverse actors as stakeholders or, alternatively, being clear about what exactly the word stakeholder means in terms of power and responsibility, is an important step in reaffirming the agency of the communities who stand to lose the most in the anthropocene.

Stroke thrombolysis with alteplase is currently recommended 0–4·5 h after stroke onset. We aimed to determine whether perfusion imaging can identify patients with salvageable brain tissue with symptoms 4·5 h or more from stroke onset or with symptoms on waking who might benefit from thrombolysis.

Given the importance of western boundary currents over a wide range of scales in the ocean, it is crucial that we understand their dynamics to accurately predict future changes. For this, we need detailed knowledge of their structure and variability. Here we investigate the jet structure of the East Australian Current (EAC), using observations from HF radars and moorings deployed at 30°S–31°S. Meandering, core velocity, width, and eddy kinetic energy (EKE) are quantified from 4 years of hourly 1.5 km resolution surface current maps (2012–2016), to obtain the most detailed representation of the surface EAC jet to date. The EAC flows predominantly over the ∼1,500 m isobath 50 km offshore but makes large amplitude displacements eastward every 65–100 days—the time scale associated with mesoscale eddy shedding at the EAC separation. Smaller‐amplitude, higher‐frequency meanders occur every 20–45 days. Using a coordinate frame that follows the jet, we show core velocity and EKE exhibit seasonality in both magnitude and variance, being maximum in summer (1.55 m s−1mean core velocity), minimum in winter (0.8 m s−1). However, it is the eddy‐shedding time scale that dominates jet variability. As the EAC moves shoreward, shelf temperature and along‐stream velocity vary linearly with jet movement, within ∼35 km of the core. The EAC is within this range 75% of the time, demonstrating its importance to the shelf circulation. Temperature and velocity fluctuations at the 70 m (100 m) isobath are more influenced by wind (EAC encroachment), with the strongest response occurring when wind and EAC act constructively. Meandering, core velocity, width, and eddy kinetic energy of the East Australian Current exhibit dominant variability at 65–100 daysAn annual cycle in the EAC core velocity and eddy kinetic energy has a maximum mean magnitude and variance in summer and minimum in winterOnshore movement of the EAC linearly increases shelf temperature and along‐stream velocity within a range of ∼35 km from its core

The structure and variability of the Florida Current between 25° and 26°N are investigated using HF radar ocean current measurements to provide the most detailed view of the surface jet to date. A 2‐D jet coordinate analysis is performed to define lateral displacements of the jet in time (meandering), and associated structural variations over a 2 year period (2005–2006). In the jet coordinate frame, core speed has a median value of ∼160 cm s−1at the central latitude of the array (25.4°N), with a standard deviation (STD) of 35 cm s−1. The jet meanders at timescales of 3–30 days, with a STD of 8 km, and a downstream phase speed of ∼80 km d−1. Meandering accounts for ∼45% of eddy kinetic energy computed in a fixed (geographical) reference frame. Core speed, width, and shear undergo the same dominant 3–30 day variability, plus an annual cycle that matches seasonality of alongshore wind stress. Jet transport at 25.4°N exhibits a different seasonality to volume transport at 27°N, most likely driven by input from the Northwest Providence Channel. Core speed correlates inversely with Miami sea level fluctuations such that a 40 cm s−1deceleration is associated with a ∼10 cm elevation in sea level, although there is no correlation of sea level to jet meandering or width. Such accurate quantification of the Florida Current's variability is critical to understand and forecast future changes in the climate system of the North Atlantic, as well as local impacts on coastal circulation and sea level variability along south Florida's coastline. The Florida Current surface jet exhibits dominant variability from 3 to 30 days in meandering, core speed, width, and shearThe jet structure undergoes a robust annual cycle in core speed, width, and shear, corresponding to local wind stressThe annual cycle of jet transport is very different between 25.5°N and 27°N, likely driven by input from the Northwest Providence Channel

This article introduces the concept of ‘mundane bioenergy’, the largest source of renewable energy utilized by human society. While the term ‘renewable energy’ evokes images of solar panels and wind turbines, most renewable energy is used in a different form. This ‘mundane’ and largely invisible form of energy use takes place when families burn wood, dung, charcoal, and crop residue in cookstoves for their subsistence needs. We call on more energy ethnographers to grapple with mundane energy issues and strengthen this small but growing field of scholarship. Limited ethnographic scholarship on mundane energy issues leads to a partial understanding of emic perspectives and failed development initiatives. By sharing insights from our ongoing ethnographic research on mundane bioenergy, we demonstrate the value of bringing such insights into conversation with research in energy studies.

Introduction:Anticoagulation reduces recurrent ischemic stroke based on clinical definitions in patients with atrial fibrillation (AF). However, neuroimaging registries suggested a significant proportion developed ischemic lesions on magnetic resonance imaging (MRI) at 12 months follow up. The rate of early recurrent ischemic stroke identified by MRI remains unclear. ATTUNE (Atrial fibrillation in stroke - Utility of Neuroimaging Evaluation) is a prospective, multicentre study of clinical and radiological outcomes in patients commenced on anticoagulation after ischaemic stroke or TIA. We aimed to investigate the incidence of early ischemic stroke on MRI in this group of patients who were anticoagulated.Aims/Methods:We performed an interim analysis of the ATTUNE database to determine the proportion of patients with radiological evidence of infarction and haemorrhage on (MRI), one month after index ischemic stroke or transient ischemic attack (TIA). MRIs performed at one month were analysed independently by two experienced neuroimage assessors and the number of new infarcts and haemorrhages determined for each patient.Results:A total of 216 patients were analysed. The median age was 74 (IQR 68-81). Anticoagulation was commenced a median of 4 days after index event (IQR 2-6). Twenty-eight patients had new infarcts on follow-up MRI (13%). Fifty-six had new haemorrhage on follow up MRI (26%). Of these, 41 patients had hemorrhagic transformation of the initial infarct and 15 had a remote haemorrhage.Conclusion:There is a high rate of recurrent ischemic lesions and haemorrhages on MRI in patients commenced on anticoagulation within 30 days of index stroke or TIA.

After the surface water and ocean topography (SWOT) satellite launches in 2022, an in‐situ field campaign will be conducted to estimate the ocean state for calibration and validation (CalVal) purposes. It is demonstrably difficult to capture the sea surface height (SSH) features that are the focus of SWOT, with short time periods (<20 days) and fine‐scale spatial structures (15–150 km). Therefore, a critical component of the SWOT CalVal will be a data assimilation (DA) system coupled to a primitive equation numerical model that can estimate: (a) the 2D SSH over the SWOT swaths, and (b) the 3D dynamical (velocity) field. To explore the ability of DA to meet the challenges of SWOT fine‐scale observations, a multiscale DA system based on an extended 3D variational method has been developed. Here, we present a strategic evaluation of this DA system, with a focus to assimilate in‐situ data from an observing system to best represent the fine‐scale ocean variability at the CalVal site. The DA estimate is compared to independent observations taken during the 2019 pre‐launch field campaign 300‐km off Monterey Bay, California. The key result is this DA system can reconstruct the upper 500‐m steric height with O(1‐cm) error at hourly resolution, and subcentimeter error for periods longer than 2 days. The surface water and ocean topography (SWOT) satellite mission is the first of its kind to launch. It will provide unprecedented measurements of the sea surface height in two dimensions (2‐D) and shorter spatial scales than previously possible. These measurements will allow oceanographers to study new scales of ocean variability and infer the ocean current velocity field. After SWOT launches, the accuracy of its measurements will need to be verified with observations made using standard instrumentation whose accuracy is well known. However, the cost to produce equivalent measurements for comparison with 2‐D high‐resolution SWOT observations is prohibitive, so the instruments to be deployed are only sufficient to evaluate a small portion of the satellite footprint. To better understand the satellite measurements, the plan is to combine the instrument measurements with a numerical ocean model that provides a four‐dimensional best‐estimate of the ocean state. This is called data assimilation (DA). In this paper, we evaluate a DA system developed to address these challenges, and show its successful performance using observations from a pre‐launch field campaign in 2019. Data assimilation (DA) of routine observations of large/mesoscale circulation allows effective assimilation of mooring data at fine scalesMooring DA reconstructs 0‐ to 500‐m hourly steric height with O(1‐cm) error, and subcentimeter error for periods longer than 2‐dayDA performance relies on observing system design; capturing the 2D horizontal gradient field is important for SWOT evaluation Data assimilation (DA) of routine observations of large/mesoscale circulation allows effective assimilation of mooring data at fine scales Mooring DA reconstructs 0‐ to 500‐m hourly steric height with O(1‐cm) error, and subcentimeter error for periods longer than 2‐day DA performance relies on observing system design; capturing the 2D horizontal gradient field is important for SWOT evaluation

We present a mapping methodology to improve the resolution of gridded sea surface height (SSH) from multisatellite along‐track measurements, and apply it in the California Current system. This is motivated by the upcoming Surface Water and Ocean Topography (SWOT) satellite mission, which will collect novel high‐resolution wide‐swath SSH measurements. The calibration/validation of SWOT will be in the California Current and requires independent observations of SSH spatial variability. Our objective was to discover how far we could push the space–time resolution of SSH maps based on the existing altimetry constellation. Currently, the best SSH maps for the region are from AVISO's global product based on optimal interpolation (OI). Our methodology is based on 2‐D variational analysis (2DVAR), and we address some limitations of the AVISO OI global parameterization that restrict the resolution. Key improvements are (1) use of a background field incorporating mesoscale information, as opposed to a long‐term mean field; (2) optimized regional parameters; and (3) a representation error term in the observational error covariance matrix to account for the spread of measurements in time. Using a suite of independent remote and in situ observations, we show the 2DVAR method can produce higher‐resolution SSH maps in the California Current region that successfully capture smaller‐scale ocean features than AVISO, at the expense of an increase in noise. Satellite altimeters measure sea surface height (SSH) along one‐dimensional tracks across the ocean. Multiple tracks taken over a time window can be mapped onto a regularly spaced longitude‐latitude‐time grid to provide information of ocean variability that allows for a range of analyses. Here, we revisit the mapping process, motivated by the upcoming Surface Water and Ocean Topography (SWOT) satellite mission that will provide unprecedented high‐resolution measurements of SSH. SWOT will be calibrated/validated in the California Current, but currently, the best maps for comparison are from a global product not tailored to the region. While along‐track measurements resolve the SSH signal down to ~65 km, these maps only resolve scales > 200 km. Our goal was to increase map resolution by retaining more of the along‐track SSH signal. We developed a mapping methodology based on variational analysis. The new maps have higher variability at smaller scales, at the expense of an increase in noise. We show these maps compare better to independent data from in situ observing platforms, coastal radar, and satellite imagery of temperature and chlorophyll‐a. The ability to resolve shorter space–time scales of variability can have important implications for the study of ocean dynamics from altimetry. We develop a mapping methodology to grid multisatellite along‐track measurements of sea surface height in the California Current systemThis variational method prescribes regionally optimized parameters, an improved background field, and an observational representation errorThe new maps retain finer‐scale signals from the along‐track observations and compare well with a suite of independent observations

In western boundary current systems, sharp velocity gradients between the poleward flowing jet and coastal waters generally act to inhibit cross‐shelf exchange. Downstream of jet separation, dynamic mesoscale eddies dominate the flow. In the East Australian Current System, counter‐rotating eddy dipoles are often present which, in the appropriate configuration, have potential to drive cross‐shelf transport. However, this eddy dipole mode is poorly understood in the framework of cross‐shelf exchange and the effect of these structures on shelf waters is uncertain. Using 25 years of satellite altimetry, as well as in situ sampling of a typical dipole event, we investigate the characteristics of eddy‐driven cross‐shelf exchange. We show that the maximum onshore velocity is driven by an eddy dipole structure and occurs in a defined latitudinal band between 33°S and 34°S more than 50% of the time. We sample a typical eddy dipole and find a strong onshore jet, 37 km wide, with velocities up to 1.78 m s −1and a transport of at least 16 Sv. Hydrographic data from an autonomous underwater glider show that this jet manifests on the shelf as a subsurface intrusion of warm salty water extending from offshore up onto the midshelf. In the light of climatic changes in western boundary current transport and the increase in their eddy kinetic energy, understanding eddy‐driven cross‐shelf exchange is important to predict future changes to the shelf water mass. An eddy dipole mode is the main driver of cross‐shelf transport in the East Australian Current extensionDipole events can result in onshore velocities up to 1.78 m s −1, with a maximum transport at 33–34°SWater from the observed dipole jet is advected from offshore up to the midshelf in the form of a warm salty intrusion of offshore water