Journals
2026 EN
Sullivan Joseph · Perry M. Scott · Scheffer Ingrid E.
+26 more
Abstract Objective Dravet syndrome (DS) is a developmental and epileptic encephalopathy characterized by drug‐resistant seizures and developmental slowing. Although cognitive and executive function deficits have been described, their early trajectory is not well understood. Methods The prospective ENVISION natural history study (NCT04537832) assessed cognitive, executive, and adaptive function in children younger than 5 years of age with SCN1A + DS every 6 months for up to 2 years using Bayley Scales of Infant and Toddler Development, 3rd Edition (BSID‐III), Wechsler Preschool & Primary Scale of Intelligence, 4th Edition (WPPSI‐IV), Vineland Adaptive Behavior Scales, 3rd Edition (VABS‐3), Behavior Rating Inventory of Executive Function – Preschool Version (BRIEF‐P), and Pediatric Evaluation of Disability Inventory (PEDI). Results Fifty‐eight children were enrolled, with 47% younger than age 2 years. At least 80% of children did not achieve age‐appropriate milestones. Mean BSID‐III Cognitive raw scores increased minimally, with age‐equivalent gains of only 3 months over 1.5 years. Mean Cognitive Composite scores declined significantly by Month 12 (from 81.6 to 72.2; change: –11.0, 95% confidence interval [CI]: −15.3 to −6.8), signaling a widening gap compared with neurotypical development. Executive function worsened, with mean BRIEF‐P Global Executive Composite T‐scores increasing by 3.2 points/year. For some participants, scores were 5 standard deviations (SD) above the normative mean, reflecting abilities profoundly below age expectations (bottom .00003% of the population). Adaptive functioning worsened, with mean VABS‐3 Adaptive Behavior Composite decreasing from 78.7 to 68.1 over 1.5 years (change: –9.0, 95% CI: −11.9 to −6.1) and greater decline among children <2 years at enrollment, with scores decreasing by ~15 points (1 SD). Over half of children >3 years could not remove clothing independently; and when placed on a toilet, 48% could not use it. Significance Infants and young children with SCN1A + DS show significant and progressive developmental slowing across several domains, highlighting urgent need for therapies to mitigate the devastating impact on individuals and families.
Journals
2026 EN
Soni Aayesha J. · Burbano M. Claudia · Couper R. Grace
+14 more
Abstract Objective This study was undertaken to determine whether bilateral independent or unclear (BI/U) scalp electroencephalographic (EEG) ictal onset patterns may predict the diagnostic yield of stereo‐electroencephalography (SEEG) and inform surgical decision‐making in patients with focal drug‐resistant epilepsy. Methods We conducted a retrospective cohort study of consecutive patients with focal drug‐resistant epilepsy and BI/U ictal onset on scalp EEG who underwent SEEG evaluation at our center between January 2012 and December 2024. All patients had undergone noninvasive and invasive presurgical assessments. Surgical outcomes were determined using the Engel classification following at least 1 year of postoperative follow‐up. A blinded decision validation substudy was also performed, where the team made decisions regarding SEEG and surgical interventions when patients found to have a single SEEG seizure onset zone (SOZ) were presented. Responses were stratified to inform the added diagnostic value of SEEG. Results Of 255 SEEG cases screened, 84 patients (33%) had BI/U ictal onset on scalp EEG. The cohort was 56% female, with a median seizure onset age of 12 years (interquartile range = 6–20); 65.5% had temporal lobe epilepsy (TLE). A single SOZ was identified in 14.3% of cases (TLE: 14.5%, extratemporal: 13.8%). These patients had shorter SEEG recording durations (mean = 11 vs. 15.79 days in those with multifocal SEEG SOZs, p = .009). Curative focal resections were performed in 12% ( n = 10), with long‐term Engel I outcomes achieved in one patient of the entire cohort (1.2%). Palliative resections occurred in 26% ( n = 22), with Engel I outcomes in 7% ( n = 6). In 50% of the blinded cases, the epilepsy surgery team reported that they would not have recommended SEEG based on phase I data. Significance In patients with BI/U ictal onset on scalp EEG, the likelihood of identifying a single SEEG SOZ, and subsequently achieving seizure freedom, is low. Scalp EEG ictal onset patterns may aid in triaging candidates for invasive evaluation, informing patients regarding presumed SEEG outcome, and avoiding unnecessary surgical procedures.
Journals
2026 EN
Bergman Jordan. · Robichaud Jessica A. · McCutcheon Jasper
+16 more
ABSTRACT Connectivity is a multifaceted concept that has important implications for the management and conservation of marine and freshwater fishes. We developed a conceptual framework that encompasses multiple, interrelated categories of connectedness, including landscape (e.g., structural, functional) connectivity and ecological (e.g., trophic, genetic, demographic) connectivity, that together shape the flow of organisms, energy and information across ecosystems. We also synthesised six key methods that can be used to study connectivity of fishes: (1) telemetry, including satellite, acoustic, radio and passive integrated transponders (PIT), (2) mark‐recapture, (3) environmental tracers, including stable isotopes and otolith‐microchemistry, (4) genetics, (5) community structure analysis and (6) emerging technologies and tools (e.g., remote sensing and artificial intelligence). For each method, we describe the categories of connectivity it can assess and provide real‐world examples where they have been effectively used. We also identify limitations of each method. This article highlights the diverse and evolving toolbox of methods used to assess fish connectivity, underscoring the need for continued collaboration, innovation and integration of new approaches to refine our understanding and address remaining challenges in this critical area of aquatic ecology and fisheries management.
Journals
2026 EN
Adeli Kevin A. · Neff Bryan D. · Cooke Steven J.
ABSTRACT Freshwater biodiversity is increasingly threatened by invasive species, which can disrupt native fish populations and the fisheries they support. Must‐kill regulations, which prohibit the live release of invasive fish caught by recreational anglers, are a management strategy that can be implemented to limit the negative effects of invasive fish populations. Our review of angling regulations around the globe revealed that must‐kill regulations for numerous species were frequently enacted in countries including Canada, Japan, and the USA. Suggested benefits of must‐kill regulations included limiting invasive species population size and preventing their dispersal, among others. While these benefits were plausible, we found no rigorous assessments of their effectiveness. Moreover, must‐kill regulations can introduce concerns such as angler opposition and species misidentification. Here, we bolstered sparse evidence with anecdotes and perspectives to identify potential advantages and drawbacks of must‐kill regulations. We also provided guidelines for implementing must‐kill regulations that emphasize strategies to increase the likelihood of success while minimizing unintended consequences. Specific guidelines vary depending on management objectives, but generally include a preliminary feasibility and risk assessment followed by post‐implementation monitoring of efficacy and consequences.
Journals
2026 EN
Choi JangGeun · Carloni Joshua T. · Gutzler Benjamin C.
+4 more
ABSTRACT We developed a particle tracking model for the transport and dispersion of American lobster ( Homarus americanus ) larvae for the Gulf of Maine (GoM) that considers both passively drifting larval stages and their swimming ability during the postlarval (pre‐settlement) stage. The model takes into account two characteristics of the postlarval stage: directional swimming toward shallower regions and diel fluctuations of their swimming speed. Diffusivity (lateral mixing), based on surface GPS drifter observations, was also considered and used to validate this model. Numerical experiments, using the hydrodynamics predicted by the Gulf of Maine Operational Forecasting System (GoMOFS) model, were conducted to test the potential impact of postlarval swimming ability on successful settlement on suitable habitat (defined as regions shallower than 20 m). The results of this experiment showed that elevated swimming ability (18 cm/s) in postlarvae significantly improves settlement success compared to trials modeling postlarvae with a diminished swimming ability (7 cm/s), or no swimming ability (control) at all. In contrast, diel swimming behavior in postlarvae slightly decreased successful settlement. In addition, ocean drifter observations and numerical simulations consistently revealed that successful settlement decreases the further the initial release point of larvae is from the coast. Combined, these experiments indicate that both the swimming ability of postlarvae and the distance they are from shore when they hatch are critical factors that influence their potential to reach viable settlement locations in the GoM. These data also suggest that if the GoM continues to warm, and females move further offshore to avoid warmer inshore waters, the settlement success of their larvae may be compromised.
Journals
2026 EN
Li Feng · Xin Qinchuan · Green Julia K.
+8 more
ABSTRACT Drought propagation from meteorological to soil drought marks a critical phase in regulating vegetation water–carbon dynamics, yet the response trajectories of water‐use efficiency (WUE) during these events remain poorly understood. Here, combining global flux tower observations with simulations from Earth System Models (ESMs), we quantified the spatiotemporal patterns of drought propagation characteristics, identified WUE response trajectories for characteristic‐specific droughts, and investigated their dominant drivers. We found that 58% of soil droughts follow meteorological droughts. Most sites experience drought propagation events with increasing intensity, faster propagation, and shorter intervals. Among all identifiable trajectories, nonmonotonic patterns account for approximately 60%. WUE response trajectories generally follow continuous and nonmonotonic patterns, dominated by a rise‐then‐fall pattern. This pattern reflects a process in which vegetation functions regulated by stomatal behavior are initially stressed and then partially recover. Intra‐site variability is extremely pronounced, mainly driven by event‐specific thermal factors such as air temperature and net radiation. ESMs reproduce broad site‐level prevalence of nonmonotonic patterns, but show discrepancies in the relative importance of drivers due to the coupling of different land surface models. These findings challenge the notion of fixed vegetation functional responses and highlight the dynamic variability of response trajectories in relation to event‐specific characteristics, and provide concrete diagnostics to guide model improvements.
Journals
2026 EN
Dolan Maria · MusettaLambert Jordan · Chin Krista S.
+5 more
ABSTRACT For many Arctic rivers and streams, climate‐driven intensification of permafrost thaw slumping is a major source of disturbance to aquatic habitats. Thaw slumps are dynamic landforms that severely increase total suspended solids (TSS) and nutrients in downstream reaches and can persist over decades. Effects may differ in magnitude as slumps cycle through periods of higher and lower activity, with expansion of retrogressive slumps increasing over time. Increases in TSS are known to cause reduced invertebrate abundance and diversity in impacted watersheds; however, it remains unclear if water quality and critical aquatic biodiversity have recovered after prolonged exposure to slumps. Here, we examined decadal‐scale effects of slumps and environmental change on benthic macroinvertebrates (BMI) by comparing environmental and BMI data collected between 2010–2014 and a recent sampling campaign from 2021. High TSS and nutrient concentrations observed during 2010–2014 persisted in slump‐impacted sites in 2021, with no significant change in TSS and total nutrient concentrations after the 10‐year exposure period. TSS continued to act as a nonspecific stressor on BMI, as abundance remained significantly lower in impacted streams compared to reference streams. Although total abundance within reference and impacted sites did not differ significantly between sampling periods, abundance and richness of disturbance tolerant taxa was greater in 2021 as compared to 2010–2014 across all sites, with differences linked to lower precipitation in 2021. These community compositional changes were reflected in increased Shannon‐Weiner diversity between sampling campaigns. Overall, the number of thaw slumps upstream was an important driver of both BMI abundance and diversity across sampling periods and will likely continue to be an important determinant of benthic macroinvertebrate communities as the number and size of thaw slumps continues to increase across the circumpolar Arctic.
Journals
2026 EN
Farnole Patrick · Ferguson Steven H. · Haddon Antoine
+3 more
ABSTRACT Understanding how marine habitats are changing with a warming Arctic is essential for conservation, management, and adaptation strategies bearing tangible consequences for Arctic communities and ecosystems. Ringed seals and bearded seals rely on specific ice and snow conditions to support critical life history events affecting survival and reproduction. Here, we develop a panarctic habitat suitability model linking life events and environmental conditions. With Earth System Models, we simulate habitat over 1850–2100, revealing a relatively stable past habitat contrasting with rapid regional shifts in contemporary simulations and future projections. Core historical habitats are projected to decline, but two regions arise as potential refugia—the East Siberian Sea and Canadian Arctic Archipelago—that could support ice seal populations towards 2100. These findings underscore the importance of refined monitoring and regional conservation strategies for ringed and bearded seals, and their unique ecosystem.
Journals
2026 EN
Sokol Noah W. · Foley Megan M. · Blazewicz Steven J.
+9 more
ABSTRACT Drought effects are pervasive in terrestrial ecosystems, yet there is limited understanding of how drought impacts the transformation of plant carbon (C) inputs to mineral‐associated organic matter (MAOM)—the largest and slowest‐cycling pool of soil organic carbon (SOC). In a 12‐week 13 C‐CO 2 greenhouse labeling experiment, we tracked the formation of MAOM derived from the two dominant sources of plant C input to the mineral soil—living root inputs ( 13 C‐rhizodeposits) and decaying root inputs ( 13 C‐root detritus)—under normal moisture and droughted conditions in a semiarid grassland soil. At the end of the 12‐week period, we also measured the persistence of 13 C‐MAOM formed from rhizodeposits versus root detritus via a subsequent persistence assay. Drought reduced the formation of MAOM derived from living roots by decreasing rhizodeposits, reducing microbial growth rates, and altering the composition of organic matter, lipids, and metabolites. Drought initially delayed the formation of MAOM derived from root detritus by slowing the early stages of root litter decomposition (week 4–8), but did not decrease total MAOM formation by the end of the 12‐week period. Notably, drought enhanced the persistence of MAOM derived from root detritus, but did not influence the persistence of MAOM derived from rhizodeposits. Our results provide some of the first direct evidence that drought can reduce the formation of MAOM in a grassland soil, but may enhance its persistence, based on the source of plant input from which MAOM is derived.
Journals
2026 EN
Salazar Jhan C. · Algar Adam C. · Poe Steven
+2 more
ABSTRACT Aim The evolution of montane species provides critical insights into the drivers of adaptation and diversification. Topographic complexity, a defining feature of many mountainous landscapes, promotes ecological and geographic isolation, often accelerating speciation rates. However, the extent to which topographic complexity directly shapes diversification remains unresolved. Here, we investigate the evolutionary dynamics of Anolis lizards across Neotropical mountain ranges to test two hypotheses: (1) higher elevation environments promote higher speciation rates in species that inhabit them; and (2) greater topographic complexity and climatic stability (i.e., lower past climatic‐change velocity) positively influence speciation rates. Location The Americas. Time Period Present. Major Taxa Studied Anolis lizards. Methods We gathered topographic complexity and past climatic‐change velocity data for 303 anole species and performed phylogenetic analyses to assess how speciation rates change across mountain ranges in the Americas. Results We found that topographic complexity and past climatic‐change velocity do not significantly influence speciation rates, diverging from prior studies that link rugged landscapes or past climatic‐change velocity to high diversification rates. Main Conclusions Our findings challenge assumptions about the direct role of topographic complexity in speciation, highlighting the need to consider multifaceted ecological and biogeographical factors driving evolutionary processes. By disentangling the relative contributions of climatic stability (i.e., lower past climatic‐change velocity) and topographic heterogeneity, this study highlights the complex dynamics shaping biodiversity in tropical mountains and calls for further integrative approaches to understand species diversification in the face of climatic and geological change.