ECPR Survivor Estimates: A Simulation-Based Approach to Comparing ECPR Delivery Strategies.

Objective: The number of out-of-hospital cardiac arrest (OHCA) patients who may benefit from prehospital extracorporeal cardiopulmonary resuscitation (ECPR) is yet to be elucidated. Patient eligibility is determined both by case characteristics and physical proximity to an ECPR service. We applied accessibility principles to historical cardiac arrest data, to identify the number of patients who would have been eligible for prehospital ECPR in Sydney, Australia, and the potential survival benefit had prehospital ECPR been available.Methods: The New South Wales cardiac arrest registry between January 2017 to June 2021 included 39,387 cardiac arrests. We retrospectively defined two groups: 1) possible ECPR eligible arrests that would have triggered activation of a team, and 2) ECPR eligible arrests, those arrests that met ECPR inclusion criteria and remained refractory. Transport accessibility modeling was used to ascertain the number of arrests that would have been served by a hypothetical prehospital service and the potential survival benefit.Results: There were 699 arrests screened as possibly ECPR eligible in the Sydney metropolitan area, 488 of whom were subsequently confirmed as ECPR eligible refractory OHCA. Of these, 38% (n = 185) received intra-arrest transfer to hospital, with 37% (n = 180) arriving within 60 min. Using spatial and transport modeling, a prehospital team located at an optimal location could establish 437 (90%) patients onto ECMO within 60 min, with an estimated survival of 48% (IQR 38-57). Based on existing survival curves, compared to conventional CPR, an optimally located prehospital ECPR service has the potential to save one additional life for every 3.0 patients.Conclusions: A significant number of historical OHCA patients could have benefited from prehospital ECPR, with a potential survival benefit above conventional CPR.

Two-item same/different discrimination in rhesus monkeys (Macaca mulatta).

Almost all nonhuman animals can recognize when one item is the same as another item. It is less clear whether nonhuman animals possess abstract concepts of "same" and "different" that can be divorced from perceptual similarity. Pigeons and monkeys show inconsistent performance, and often surprising difficulty, in laboratory tests of same/different learning that involve only two items. Previous results from tests using multi-item arrays suggest that nonhumans compute sameness along a continuous scale of perceptual variability, which would explain the difficulty of making two-item same/different judgments. Here, we provide evidence that rhesus monkeys can learn a two-item same/different discrimination similar to those on which monkeys and pigeons have previously failed. Monkeys' performance transferred to novel stimuli and was not affected by perceptual variations in stimulus size, rotation, view, or luminance. Success without the use of multi-item arrays, and the lack of effect of perceptual variability, suggests a computation of sameness that is more categorical, and perhaps more abstract, than previously thought.

Scheduling optimisation of alcohol test sites.

Drink driving is an infamous factor in road crashes and fatalities. Alcohol testing is a major countermeasure, and random breath tests (RBTs) deter tested drivers and passersby (observers who are not tested). We propose a genetic algorithm (GA)-based RBT scheduling optimisation method to achieve maximal deterrence of drink driving. The RBT schedule denotes the daily plan of where, when, and for how long tests should occur in the road network. The test results (positive and negative) and observing drivers are considered in the fitness function. The limited testing resource capacity is modeled by a number of constraints that consider the total duration of tests, the minimum and maximum duration of a single test site, and the total number of test sites during the day. Clustering of the alcohol-related crash data is used to estimate the matrix for drink driving on the scheduled day. The crash data and traffic flow data from Victoria, Australia are analysed and used to describe sober/drink driving. A detailed synthetic example is developed and a significant improvement with 150% more positive results and 59% more overall tests is observed using the proposed scheduling optimisation method.

Techno-Economic Analysis of Atmospheric Water Harvesting Across Climates.

Drinking water scarcity is a global challenge as groundwater and surface water availability diminishes. The atmosphere is an alternative freshwater reservoir that has universal availability and could be harvested as drinking water. In order to effectively perform atmospheric water harvesting (AWH), we need to (1) understand how different climate regions (e.g., arid, temperate, and tropical) drive the amount of water that can be harvested and (2) determine the cost to purchase, operate, and power AWH. This research pairs thermodynamics with techno-economic analysis to calculate the water productivity and cost breakdown of a representative condensation-based AWH unit with water treatment. We calculate the monthly and annual levelized cost of water from AWH as a function of climate and power source (grid electricity vs renewable energy from solar photovoltaics (PV)). In our modeled unit, AWH can provide 1744-2710 L/month in a tropical climate, 394-1983 L/month in a temperate climate, and 37-1470 L/month in an arid climate. The levelized cost of water of AWH powered by the electrical grid is $0.06/L in a tropical climate, $0.09/L in a temperate climate, and $0.17/L in an arid climate. If off-grid solar PV was purchased at the time of purchasing the AWH unit to power the AWH, the costs increase to $0.40/L in an arid climate, $0.17/L in a temperate climate, and $0.10/L in a tropical climate. However, if using existing solar PV there are potential cost reductions of 4.25-5-fold between purchasing and using existing solar PV, and 2-3-fold between using the electrical grid and existing solar PV, with the highest cost reductions occurring in the tropical climate. Using existing solar PV, the levelized cost of AWH is $0.09/L in an arid climate, $0.04/L in a temperate climate, and $0.02/L in a tropical climate.

Improving access to extracorporeal membrane oxygenation for out of hospital cardiac arrest: pre-hospital ECPR and alternate delivery strategies.

BACKGROUND: The use of extracorporeal membrane oxygenation (ECPR) in refractory out-of-hospital cardiac arrest (OHCA) patients is usually implemented in-hospital. As survival in ECPR patients is critically time-dependent, alternative models in ECPR delivery could improve equity of access. OBJECTIVES: To identify the best strategy of ECPR delivery to provide optimal patient access, to examine the time-sensitivity of ECPR on predicted survival and to model potential survival benefits from different delivery strategies of ECPR. METHODS: We used transport accessibility frameworks supported by comprehensive travel time data, population density data and empirical cardiac arrest time points to quantify the patient catchment areas of the existing in-hospital ECPR service and two alternative ECPR strategies: rendezvous strategy and pre-hospital ECPR in Sydney, Australia. Published survival rates at different time points to ECMO flow were applied to predict the potential survival benefit. RESULTS: With an in-hospital ECPR strategy for refractory OHCA, five hospitals in Sydney (Australia) had an effective catchment of 811,091 potential patients. This increases to 2,175,096 under a rendezvous strategy and 3,851,727 under the optimal pre-hospital strategy. Assuming earlier provision of ECMO flow, expected survival for eligible arrests will increase by nearly 6% with the rendezvous strategy and approximately 26% with pre-hospital ECPR when compared to the existing in-hospital strategy. CONCLUSION: In-hospital ECPR provides the least equitable access to ECPR. Rendezvous and pre-hospital ECPR models substantially increased the catchment of eligible OHCA patients. Traffic and spatial modelling may provide a mechanism to design appropriate ECPR service delivery strategies and should be tested through clinical trials.

Specialized areas for value updating and goal selection in the primate orbitofrontal cortex.

The macaque orbitofrontal cortex (OFC) is essential for selecting goals based on current, updated values of expected reward outcomes. As monkeys consume a given type of reward to satiety, its value diminishes, and OFC damage impairs the ability to shift goal choices away from devalued outcomes. To examine the contributions of OFC's components to goal selection, we reversibly inactivated either its anterior (area 11) or posterior (area 13) parts. We found that neurons in area 13 must be active during the selective satiation procedure to enable the updating of outcome valuations. After this updating has occurred, however, area 13 is not needed to select goals based on this knowledge. In contrast, neurons in area 11 do not need to be active during the value-updating process. Instead, inactivation of this area during choices causes an impairment. These findings demonstrate selective and complementary specializations within the OFC.