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The unprecedented expansion of lithium mining in closed‐basin brines is sparking concerns that mine‐related brine abstraction will stress freshwater resources and harm sensitive wetland ecosystems. These fears stoke preexisting conflicts between indigenous communities, governments, and mining interests. However, until now there has not been a comprehensive evaluation of how groundwater flux to wetlands in these systems responds to brine and freshwater abstraction to support these concerns. This study characterizes the hydrogeologic relationship between both brine and freshwater abstraction and groundwater discharge to wetlands in closed‐basin brine systems utilizing groundwater‐flow models representing three closed‐basin brine system endmembers. The models show that regardless of hydrogeologic conditions, fresh groundwater abstraction has a 200%–2,300% larger impact than halite brine abstraction on groundwater‐dependent wetlands over a 200‐year period. The primary control mechanisms for groundwater discharge response to abstraction are proximity to the abstraction point and density‐driven storage flux, which magnifies the impacts of freshwater abstraction and buffers the impacts of brine abstraction. Observations of changes in wetland vegetation near existing lithium brine mines show a 90% reduction in vegetated wetland area in response to freshwater abstraction but no observable change in response to brine abstraction, in agreement with the results of the modeling study. These findings demonstrate that minimizing freshwater use is more effective at protecting groundwater‐dependent wetlands than limiting brine drawdowns in closed‐basin brine systems.

Demand for lithium for batteries is growing rapidly with the global push to decarbonize energy systems. The Salar de Atacama, Chile holds ∼42% of the planet's reserves in the form of brine hosted in massive evaporite aquifers. The mining of these brines and associated freshwater use has raised concerns over the environmental responsibility of lithium extraction, yet large uncertainties remain regarding fundamental aspects of governing hydrological processes in these environments. This incomplete understanding has led to the perpetuation of misconceptions about what constitutes sustainable or renewable water use and therefore what justifies responsible allocation. We present an integrated hydrological assessment using tritium and stable oxygen, and hydrogen isotopes paired with remotely sensed and terrestrial hydroclimate data to define unique sources of water distinguished by residence time, physical characteristics, and connectivity to modern climate. Our results describe the impacts of prolonged drought on surface and groundwaters and demonstrate that nearly all inflow to the basin is composed of water recharged >65 years ago. Still, modern precipitation is critical to sustaining important wetlands around the salar. Recent large rain events have increased surface water and vegetation extents and terrestrial water storage while mining‐related water withdrawals have continued. As we show, poor conceptualizations of these complex hydrological systems have perpetuated the misallocation of water and the misattribution of impacts. These fundamental issues apply to arid regions globally. Our new framework for hydrological assessment in these basins moves beyond calculating gross inputs‐outputs at a steady state to include all compartmentalized stores that constitute “modern” budgets. Plain Language Summary Lithium is a critical resource for the green energy transition as the primary component in lithium‐ion batteries. Most of the planet's resources occur in water‐scarce environments, like Salar de Atacama, Chile where almost half the world's supply exists. Large amounts of very salty groundwater and some freshwater is extracted to recover the lithium. Yet, persistent gaps remain in our understanding of how water moves in these environments and therefore the impacts its extraction may have on surrounding ecosystems. We employ a combination of satellite and ground‐based hydroclimatological data to assess the system. Our results show that prolonged drought and a subsequent wetter period are the primary drivers of surface hydrology changes and that most of the water here is very old, highlighting the shortcomings of current water allocations. This work presents a data‐driven framework that allows water sustainability and lithium extraction to be adequately assessed in these arid regions. Key Points Freshwater inflows and the modern water budget at Salar de Atacama are dominated by relic groundwater A drought coincident with increases in groundwater extraction complicates the attribution of specific anthropogenic environmental impacts Freshwater use and allocated water rights at Salar de Atacama appear to not meet sustainable metrics

The Carnegie Classification of Institutions of Higher Education is a commonly used framework for institutional classification that classifies doctoral-granting schools into three groups based on research productivity. Despite its wide use, the Carnegie methodology involves several shortcomings, including a lack of thorough documentation, subjectively placed thresholds between institutions, and a methodology that is not completely reproducible. We describe the methodology of the 2015 and 2018 updates to the classification and propose an alternative method of classification using the same data that relies on structural equation modeling (SEM) of latent factors rather than principal component-based indices of productivity. In contrast to the Carnegie methodology, we use SEM to obtain a single factor score for each school based on latent metrics of research productivity. Classifications are then made using a univariate model-based clustering algorithm as opposed to subjective thresholding, as is done in the Carnegie methodology. Finally, we present a Shiny web application that demonstrates sensitivity of both the Carnegie Classification and SEM-based classification of a selected university and generates a table of peer institutions in line with the stated goals of the Carnegie Classification.

More than half the world’s lithium resources are found in brine aquifers in Chile, Argentina, and Bolivia. Lithium brine processing requires freshwater, so as lithium exploration increases, accurate estimates of freshwater availability are critical for water management decisions in this region with limited water resources. Here we calculate modern freshwater inflows, such as groundwater recharge and streamflow, for 28 active or prospective lithium-producing basins. We use regional water budget assessments, field streamflow measurements, and global climate and groundwater recharge datasets. Using the freshwater inflow estimates, we calculate water scarcity using the Available Water Remaining methodology. Among all 28 basins, freshwater inflows range from 2 to 33 mm year −1 . Our results reveal that commonly used global hydrologic models overestimate streamflow and freshwater availability substantially, leading to inaccurate water scarcity classifications. Surface freshwater inflow to the Lithium Triangle of South America, a key resource for many lithium processes, has been overestimated substantially, according to a basin-scale water availability assessment in 28 basins relevant for lithium mining.

ObjectiveTo assess the neurodevelopmental outcomes of preterm neonates who received inhaled nitric oxide (iNO) in the first week of age for hypoxaemic respiratory failure (HRF).MethodsIn this retrospective cohort study, we included neonates born at <29 weeks gestational age (GA) between January 2010 and December 2018 who had a neurodevelopmental assessment at 18–24 months corrected age (CA) at one of the Canadian Neonatal Follow-Up Network clinics. The primary outcome was neurodevelopmental impairment (NDI). We performed propensity score-matched analysis to compare the outcomes of those who received and did not receive iNO.ResultsOf the 5612 eligible neonates, 460 (8.2%) received iNO in the first week of age. Maternal age, receipt of antenatal corticosteroids, GA and birth weight were lower in the iNO group compared with the no-iNO group. Neonates in the iNO group had higher illness severity scores and higher rates of preterm prolonged rupture of membranes and were small for GA. Severe brain injury, bronchopulmonary dysplasia and mortality were higher in the iNO group. Of the 4889 survivors, 3754 (77%) neonates had follow-up data at 18–24 months CA. After propensity score matching, surviving infants who received rescue iNO were not associated with higher odds of NDI (adjusted OR 1.34; 95% CI 0.85 to 2.12).ConclusionsIn preterm neonates <29 weeks GA with HRF, rescue iNO use was not associated with worse neurodevelopmental outcomes among survivors who were assessed at 18–24 months CA.

ObjectiveTo compare mortality and rates of significant neurosensory impairment (sNSI) at 18–36 months’ corrected age in infants born extremely preterm across three international cohorts.DesignRetrospective analysis of prospectively collected neonatal and follow-up data.SettingThree population-based observational cohort studies: the Australian and New Zealand Neonatal Network (ANZNN), the Canadian Neonatal and Follow-up Networks (CNN/CNFUN) and the French cohort Etude (Epidémiologique sur les Petits Ages Gestationnels: EPIPAGE-2).PatientsExtremely preterm neonates of <28 weeks’ gestation in year 2011.Main outcome measuresPrimary outcome was composite of mortality or sNSI defined by cerebral palsy with no independent walking, disabling hearing loss and bilateral blindness.ResultsOverall, 3055 infants (ANZNN n=960, CNN/CNFUN n=1019, EPIPAGE-2 n=1076) were included in the study. Primary composite outcome rates were 21.3%, 20.6% and 28.4%; mortality rates were 18.7%, 17.4% and 26.3%; and rates of sNSI among survivors were 4.3%, 5.3% and 3.3% for ANZNN, CNN/CNFUN and EPIPAGE-2, respectively. Adjusted for gestational age and multiple births, EPIPAGE-2 had higher odds of composite outcome compared with ANZNN (OR 1.71, 95% CI 1.38 to 2.13) and CNN/CNFUN (OR 1.72, 95% CI 1.39 to 2.12). EPIPAGE-2 did have a trend of lower odds of sNDI but far short of compensating for the significant increase in mortality odds. These differences may be related to variations in perinatal approach and practices (and not to differences in infants’ baseline characteristics).ConclusionsComposite outcome of mortality or sNSI for extremely preterm infants differed across high-income countries with similar baseline characteristics and access to healthcare.

Abstract Objective Survivors of extremely preterm birth are at risk of re-hospitalization but risk factors in the Canadian population are unknown. Our objective is to identify neonatal, sociodemographic, and geographic characteristics that predict re-hospitalization in Canadian extremely preterm neonates. Methods This is a retrospective analysis of a prospective observational cohort study that included preterm infants born 22 to 28 weeks’ gestational age from April 1, 2009 to September 30, 2011 and seen at 18 to 24 months corrected gestational age in a Canadian Neonatal Follow-Up Network clinic. Characteristics of infants re-hospitalized versus not re-hospitalized are compared. The potential neonatal, sociodemographic, and geographic factors with significant association in the univariate analysis are included in a multivariate model. Results From a total of 2,275 preterm infants born at 22 to 28 weeks gestation included, 838 (36.8%) were re-hospitalized at least once. There were significant disparities between Canadian provincial regions, ranging from 25.9% to 49.4%. In the multivariate logistic regression analysis, factors associated with an increased risk for re-hospitalization were region of residence, male sex, bronchopulmonary dysplasia, necrotizing enterocolitis, prolonged neonatal intensive care unit (NICU) stay, ethnicity, Indigenous ethnicity, and sibling(s) in the home. Conclusion Various neonatal, sociodemographic, and geographic factors predict re-hospitalization of extremely preterm infants born in Canada. The risk factors of re-hospitalization provide insights to help health care leaders explore potential preventative approaches to improve child health and reduce health care system costs.

Abstract Chest compression in the delivery room (CPR-DR) during neonatal resuscitation is considered as an extreme measure. When respiratory support alone is unable to establish circulatory transition, chest compression with or without epinephrine is necessary. The results of earlier studies have shown varied results in mortality and morbidity of preterm infants who received CPR-DR. To examine the relationship between need of CPR-DR in infants born between 23 and 32 weeks gestation and neonatal mortality and morbidity. This was a population-based cohort study of 23 0/7 to 32 6/7 weeks gestational age infants born at a Canadian tertiary care hospital between January 1, 2007 and December 31, 2016. Data were retrieved from the Neonatal-Perinatal database. Neonatal mortality and morbidities were examined between infants who did and did not need CPR-DR. Of 1443 newborns meeting study criteria, 55 (3.8%) received CPR-DR. On bivariate analysis, outcome of infants requiring CPR-DR was associated with higher mortality (40% vs. 5.8%, p <0.001), intraventricular hemorrhage grade 3 or 4 (21.8% vs. 6.1%, p <0.001), patent ductus arteriosus (54.5% vs. 27.7%, p<0.001), bronchopulmonary dysplasia (35.4% vs. 19.6%, p=0.007), need of mechanical ventilation (90.9% vs. 61.1%, p<0.001) and sepsis (23.6% vs. 13.5%, p=0.034). However, in a multivariable logistic regression analysis controlling for predictor variables, CPR-DR was only associated with increased neonatal mortality (aOR=4.41 p<0.001, 95%CI [2.18, 8.92]). While CPR-DR is associated with a high mortality rate in infants less than 32 weeks gestation, associated morbidities are largely predicted by other risk factors.

Abstract The optimal mode of delivery for preterm infants remains controversial, and routine Caesarean sections (C/S) are not recommended, except for maternal indications. Nonetheless, many preterm infants are delivered by C/S, particularly those in breech presentation, and recent retrospective data have suggested that these infants may have improved outcomes. To examine whether C/S as the mode of preterm delivery is associated with decreased mortality and improved short term outcomes. This retrospective, population-based cohort study examined infants with a gestational age between 23 0/7 weeks and 32 6/7 weeks, born between January 1, 2007 and December 31, 2016, and admitted to the Neonatal Intensive Care Unit at a single Canadian Tertiary Care hospital. Infants with major congenital anomalies were excluded. Data were abstracted from the local Neonatal-Perinatal database for all infants. Two groups, those delivered vaginally and those delivered by C/S, were compared for major neonatal outcomes including the primary outcomes of death and severe intraventricular hemorrhage (IVH), defined as grade 3 or higher. A total of 1442 infants met inclusion criteria (784 born by C/S and 658 vaginally). There was no significant difference in neonatal mortality (7.0% vs 7.1%, p=0.925) or severe IVH (6.1% vs 7.4%, p=0.317). There was, however, a significant difference in the incidence of IVH, any grade (19.9% vs 27.5%, p=0.001), which remained after controlling for other significant predictors. There were no other significant differences in the secondary outcomes examined including need for extensive resuscitation, respiratory distress syndrome, bronchopulmonary dysplasia, patent ductus arteriosus, necrotizing enterocolitis, periventricular leukomalacia, or retinopathy of prematurity. Caesarean section was not associated with decreased mortality in preterm infants, relative to vaginal births. Caesarean section was associated with a reduced rate of IVH (any grade) and there was a trend towards decreased severe IVH which may warrant further study.

Pathophysiological changes in the cortex, thalamus, and hippocampus have been implicated as contributors to motor and cognitive deficits in a number of animal models of traumatic brain injury (TBI). Indirect cerebellar injury may contribute to TBI pathophysiology because impairment of motor function and coordination are common consequences of TBI, but are also domains associated with cerebellar function. However, there is a lack of direct evidence to support this claim. Hence, in this study, a dose-response relationship of the cerebellum's susceptibility was determined at four grades of fluid percussion injury (1.5, 2.0, 2.5, and 3.0 atm) applied in the right lateral cerebral cortex of adult male Sprague-Dawley rats. Evidence suggests primary and secondary injury mechanisms resulting in selective cerebellar Purkinje neuron (PN) loss, whereas interneurons of the molecular layer were spared. The posterior region of the cerebellar vermis displayed significant PN loss (p = 0.001) at 1 day postinjury, whereas the gyrus of the horizontal fissure and gyrus of lobules III and IV exhibited delayed PN loss at higher levels of injury severity. Interestingly, neither terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL) or cleaved caspase-3 colocalized with PNs at any time point or injury severity. Expression of calbindin-28k increased in regions of greatest PN loss, suggesting that the surviving PNs possess higher calcium-buffering capacities, which may account for their survival.