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ABSTRACT Introduction Subanesthetic doses of ketamine are a promising novel treatment for suicidality; however, the evidence for predictive biomarkers is sparse. Recently, measures of complexity, including Lempel–Ziv complexity (LZC) and multiscale entropy (MSE), have been implicated in ketamine's therapeutic action. We evaluated electroencephalogram (EEG)‐derived LZC and MSE differences between responders and nonresponders to oral ketamine treatment. Methods A total of 31 participants received six single, weekly (titrated) doses of oral racemic ketamine (0.5–3 mg/kg) and underwent EEG scans at baseline (Week 0), post‐treatment (Week 6), and follow‐up (Week 10). Resting‐state (eyes closed and open) recordings were processed in EEGLAB, and complexity metrics were extracted using the Neurokit2 package. Participants were designated responders or nonresponders by clinical response (Beck Suicide Scale [BSS] score reduction of ≥ 50% from baseline to the respective timepoint or score ≤ 6) and then compared in terms of complexity across resting‐state conditions and time. Results Employing a Bayesian mixed effects model, we found strong evidence that LZC was higher in the eyes‐open compared to eyes‐closed condition, as were MSE scales 1–3. At a global level, responders displayed elevated eyes‐open baseline complexity compared to nonresponders, with these values decreasing from baseline to post‐treatment (Week 6) in responders only. Exploratory analyses revealed that the elevated baseline eyes‐open LZC in responders was spatially localized to the left frontal lobe (F1, AF3, FC1, and F3). Conclusion EEG‐complexity metrics may be sensitive biomarkers for evaluating and predicting oral ketamine treatment response, with the left prefrontal cortex bein a possible treatment response region.

Abstract Aircraft observations of the four chloromethanes: carbon tetrachloride (CCl4), methyl chloride (CH3Cl), dichloromethane (CH2Cl2), and chloroform (CHCl3), collected over North America between 2000 and 2022, were used to evaluate their vertical distributions and temporal trends in the atmosphere. We examine the vertical profiles, from the surface to the lower stratosphere (LS), of these increasingly important contributors to ozone‐depleting chlorine in both altitude and potential temperature space. Airborne chloromethane trends were compared with those measured at long‐term, ground‐based monitoring stations. Below 20 km altitude, CCl4 trends were decreasing at all levels studied in the North American atmosphere (−1.1 ppt yr−1). CHCl3 and CH2Cl2 airborne observations were comparable to ground network measurements: CHCl3 increased between 2000 and 2018 and then decreased leading to a negligible trend over the 22 years studied and CH2Cl2 has been increasing at all levels in the troposphere (+2.41 ppt yr−1, 2000–2022,

Abstract Wetlands are ecologically and culturally significant ecosystems that are experiencing biodiversity declines globally. Biomonitoring techniques that use environmental DNA (eDNA) to detect and monitor biodiversity are well established in lake, riverine, and marine ecosystems. However, their use in wetlands requires further development due to the presence of sediments that block eDNA filters to limit water filtration, alongside a lack of standardized methodology. In this study, we examined eDNA dynamics to understand spatiotemporal biodiversity patterns in an Aotearoa New Zealand wetland and to optimize their application to wetland‐specific challenges. We sampled four sites across Opuatia Wetland at three time points during an austral spring. We conducted conventional taxonomic surveys, tested three different filter sizes (1.2 μm, 5 μm, and semi‐quantitative dacron filters), and assessed our ability to detect foreign DNA (from kea; Nestor notabilis) at different time points and distances post‐release. We found significant differences in DNA sequence composition across time and space, and when using different sized filters. eDNA data generally complemented (versus replaced) conventional survey and identification methods, with certain species only detected by one method or the other. Taxonomic resolution of conventional sampling and identification methods often exceeded that of eDNA. Foreign DNA was detectable 10 m from its release point for up to 1 week post‐release. Our results provide new considerations for future eDNA research in wetland environments, where rapid biomonitoring techniques are needed to support conservation and preservation.

Abstract Background Impairment of left ventricular (LV) longitudinal function is an early marker of systolic dysfunction in hypertrophic cardiomyopathy (HCM). Aortic annular plane systolic excursion (AAPSE) is a measure of LV longitudinal function in people that has not been evaluated in cats. Hypothesis Aortic annular plane systolic excursion is lower in cats with HCM compared to control cats, and cats in stage C have the lowest AAPSE. Animals One hundred seventy‐five cats: 60 normal, 61 HCM stage B and 54 HCM stage C cats. Materials Multicenter retrospective case‐control study. Electronic medical records from 4 referral hospitals were reviewed for cats diagnosed with HCM and normal cats. HCM was defined as LV wall thickness ≥6 mm and normal cats ≤5 mm. M‐mode bisecting the aorta in right parasternal short‐axis view was used to measure AAPSE. Results Aortic annular plane systolic excursion was lower in HCM cats compared to normal cats (3.9 ± 0.9 mm versus 4.6 ± 0.9 mm, P

Abstract Objectives To establish packed cell volume (PCV) ranges for non‐pregnant, pregnant and post‐partum bitches from day 10 of proestrus, investigating any relationship with parity and litter size. Methods This prospective cohort study used 37 healthy breeding bitches to examine PCV counts from routine blood samples collected every 4 weeks, from day 10 of proestrus, as part of routine PCV monitoring. Results For pregnant (n = 19) and non‐pregnant (n = 18) bitches, PCV decreased until week 8 (corresponding to 8.5 ± 1.1 days before whelping for pregnant bitches) and recovered by 16–20 weeks after the initial sample; bitches that whelped average and large litters showed greater declines. PCV began to recover sooner for bitches that had previously whelped one or two litters compared to bitches that had previously whelped three or more litters. There was a significant three‐way interaction between time after the onset of proestrus, litter size and the number of previous litters which demonstrated that the large decrease in PCV for bitches that had previously whelped three or more litters only occurred in bitches that were expecting an average or large sized litter. Clinical Significance Chronological variation in PCV for pregnant and non‐pregnant bitches was established during the reproductive cycle. There was no evidence to suggest that routine PCV measurement for normal, healthy bitches would be beneficial. However, knowledge from this study may be useful when deciding whether to prospectively monitor a bitch where there is a history of previous pregnancy‐related anaemia, when performing a caesarean section due to the anticipated blood loss during surgery, or when examining blood profiles for post‐litter bitches.

Abstract Hypoxia in coastal waters and lakes is widely recognized as a detrimental environmental issue, yet we lack a comparable understanding of hypoxia in rivers. We investigated controls on hypoxia using 118 million paired observations of dissolved oxygen (DO) concentration and water temperature in over 125,000 locations in rivers from 93 countries. We found hypoxia (DO

Objective Systemic rheumatic conditions affect reproductive‐aged patients and often require potentially teratogenic medications. We assessed the feasibility and impact of a standardized pregnancy intention screening question (One Key Question [OKQ]) in a large academic rheumatology practice. Methods This 6‐month pilot quality improvement initiative prompted rheumatologists to ask female patients aged 18 to 49 years about their pregnancy intentions using OKQ. We administered surveys to assess rheumatologists’ barriers to and comfort with reproductive health issues. We performed chart reviews to assess uptake and impact on documentation, comparing charts with OKQ documented with 100 randomly selected charts eligible for pregnancy intention screening but without OKQ documented. Results When we compared 32 of 43 preimplementation responses with 29 of 41 postimplementation responses, the proportion of rheumatologists who reported they were very comfortable with assessing their patients’ reproductive goals increased (31%‐38%) and the proportion reporting obstetrics and gynecology (OB/GYN) referral challenges as barriers to discussing reproductive goals decreased (41%‐21%). During the implementation period, 83 of 957 (9%) eligible patients had OKQ documented in their chart. Female providers were more likely to screen than male providers (odds ratio 2.42, 95% confidence interval 1.21‐4.85). Screened patients were more likely to have their contraceptive method documented (P

Abstract Conservation of green sea turtles (Chelonia mydas) benefits from knowledge of population connectivity across life stages. Green turtles are managed at the level of genetically discrete rookeries, yet individuals from different rookeries mix at foraging grounds; therefore, rookeries may be impacted by processes at foraging grounds. Bimini, Bahamas, hosts an important foraging assemblage, but rookery contributions to this assemblage have never been resolved. We generated mitochondrial DNA sequences for 96 foraging green turtles from Bimini and used Mixed Stock Analysis to determine rookery contributions to this population using 817 and 490 base pair (bp) rookery baseline data. The MSA conducted with 817 bp data indicated that Quintana Roo, Mexico, and Central Eastern Florida contributed most to the Bimini population. The MSA conducted with 490 bp data indicated that Southwest Cuba and Central Eastern Florida contributed the most to Bimini. The results of the second MSA differ from a previous study undertaken with 490 bp data, conducted in Great Inagua, Bahamas, which suggested that Tortuguero, Costa Rica, contributed the most to that foraging assemblage. Large credible intervals in our results do not permit explicit interpretation of individual rookery contributions, but our results do indicate substantial relative differences in rookery contributions to two Bahamian foraging assemblages which may be driven by oceanic currents, rookery sizes, and possibly juvenile natal homing. Our findings may implicate a shift in contributions to the Bahamas over two decades, highlighting the importance of regularly monitoring rookery contributions and resolving regional recruitment patterns to inform conservation.

Abstract Background Treatment is indicated in dogs with preclinical degenerative mitral valve disease (DMVD) and cardiomegaly (stage B2). This is best diagnosed using echocardiography; however, relying upon this limits access to accurate diagnosis. Objectives To evaluate whether cardiac biomarker concentrations can be used alongside other clinical data to identify stage B2 dogs. Animals Client‐owned dogs (n = 1887) with preclinical DMVD prospectively sampled in Germany, the United Kingdom, and the United States. Methods Dogs that met inclusion criteria and were not receiving pimobendan (n = 1245) were used for model development. Explanatory (multivariable logistic regression) and predictive models were developed using clinical observations, biochemistry, and cardiac biomarker concentrations, with echocardiographically confirmed stage B2 disease as the outcome. Receiver operating characteristic curves assessed the ability to identify stage B2 dogs. Results Age, appetite, serum alanine aminotransferase activity, body condition, serum creatinine concentration, murmur intensity, and plasma N‐terminal propeptide of B‐type natriuretic peptide (NT‐proBNP) concentration were independently associated with the likelihood of being stage B2. The discriminatory ability of this explanatory model (area under curve [AUC], 0.84; 95% confidence interval [CI], 0.82‐0.87) was superior to NT‐proBNP (AUC, 0.77; 95% CI, 0.74‐0.80) or the vertebral heart score alone (AUC, 0.76; 95% CI, 0.69‐0.83). A predictive logistic regression model could identify the probability of being stage B2 (AUC test set, 0.86; 95% CI, 0.81‐0.91). Conclusion and Clinical Importance Our findings indicate accessible measurements could be used to screen dogs with preclinical DMVD. Encouraging at‐risk dogs to seek further evaluation could result in a greater proportion of cases being appropriately managed.

Abstract Background Executive function (EF) is associated with obesity development and self‐management. Individuals who demonstrate or self‐report poorer EF performance tend to have poorer short‐term outcomes in obesity treatment. There may be distinct behavioral self‐management strategies and EF domains related to initial weight loss as compared to weight loss maintenance. Objective To characterize EF in individuals who achieved clinically significant weight loss via behavioral intervention and examine potential differences in EF between those who maintained versus regained lost weight. Methods Participants who previously achieved ≥5% weight loss via lifestyle intervention were included (N = 44). “Maintainers” (n = 16) maintained this minimum level of weight loss for ≥1 year. “Regainers” (n = 28) regained some or all initially lost weight. Performance‐based EF, intelligence quotient, health literacy, depression, anxiety, binge eating, demographics, and medical/weight history were assessed using a cross‐sectional design. Descriptive statistics and age‐, gender‐, education‐adjusted reference ranges were used to characterize EF. Analyses of covariance were conducted to examine EF differences between maintainers and regainers. Results The sample consisted primarily of females with obesity over age 50. Approximately half self‐identified as African–American. Decision‐making performance was better in maintainers than regainers (p = 0.003, partη2 = 0.19). There were no differences between maintainers and regainers in inhibitory control, verbal fluency, planning/organization, cognitive flexibility, or working memory (ps > 0.05, partη2s = 0.003–0.07). At least 75% of the sample demonstrated average‐above average EF test performance, indicated by scaled scores ≥13 or t‐scores > 60. Conclusions Most individuals with obesity who achieved clinically significant weight loss via behavioral intervention had average to above average EF. Individuals who maintained (vs. regained) their lost weight performed better on tests of decision‐making.

Summary Objective To compare depressive symptomatology as assessed by two frequently used measures, the Beck Depression Inventory (BDI‐1A) and Patient Health Questionnaire (PHQ‐9). Methods Investigators conducted a cross‐sectional secondary analysis of data collected as part of the follow‐up observational phase of the Look AHEAD study. Rates of agreement between the BDI‐1A and PHQ‐9 were calculated, and multivariable logistic regression was used to examine the relationship between differing depression category classifications and demographic factors (ie, age, sex, race/ethnicity) or comorbidities (ie, diabetes control, cardiovascular disease). Results A high level of agreement (κ = 0.47, 95% CI (0.43 to 0.50)) was found in the level of depressive symptomatology between the BDI‐1A and PHQ‐9. Differing classifications (minimal, mild, moderate, and severe) occurred in 16.8% of the sample. Higher scores on the somatic subscale of the BDI‐1A were significantly associated with disagreement as were having a history of cardiovascular disease, lower health‐related quality of life, and minority racial/ethnic classification. Conclusions Either the BDI‐1A or PHQ‐9 can be used to assess depressive symptomatology in adults with overweight/obesity and type 2 diabetes. However, further assessment should be considered in those with related somatic symptoms, decreased quality of life, and in racial/ethnic minority populations.

Abstract Society's progress along the four corners of prepare, absorb, respond and adapt resilience square is uneven, in spite of our understanding of the foundational science and a growing sense that urgent action is needed. The resilience vignettes describe the meaning and impact of current and near‐term change in four major domains: human health impacts from air pollution, coastal inundation from sea‐level rise, damaging earthquakes in populated areas, and impacts from extreme precipitation. Given our understanding of the scientific principles, societal action, from preparation to adaption, will be critical in minimizing the negative impacts of change. The unprecedented rates of change in today's Earth system argue for urgent action in support of a resilient global society.

Abstract Trophic position and niche width are fundamental components of a species’ ecology, reflecting resource use, and influencing key demographic parameters such as somatic growth, maturation, and survival. Concepts about a species’ trophic niche space have important implications for local management and habitat protection, and can shed light about resilience to changing climate for species occurring over broad spatial scales. For elusive marine animals such as sea turtles, trophic niche is challenging to study, and researchers often rely on other metrics, such as isotopic niche, as a proxy. Here, stable isotope analysis (δ13C and δ15N values) was conducted on bulk skin tissue of 718 green turtles (Chelonia mydas) distributed among 16 foraging areas in the eastern Pacific from the USA to Chile, a range spanning ~10,000 km. Compound‐specific nitrogen isotope analysis of amino acids (CSIA‐AA) was applied to 21 turtles among seven sites. Isotopic niche space was determined via Bayesian ellipse area (BEA) and convex hull area (CHA) analyses of bulk isotope values, which were also used along with amino acid δ15N values to determine trophic position (TP). Substantial variability in bulk tissue δ13C and δ15N values was found within and among sites, and amino acid δ15N values confirmed this was largely due to spatial differences in baseline nitrogen isotopic compositions, but also to a lesser extent from TP differences among the green turtle foraging populations. Isotope niche space varied among sites, influenced by the diversity of prey types and relative input of terrestrial‐ vs. marine‐derived nutrients; BEAs were the most suitable measurement of isotopic niche space due to the larger influence of outlying values with the CHA approach. Amino acid isotope‐derived TP estimates that accounted for local habitat conditions (e.g., mixed seagrass/macroalgae diet) performed the best among several approaches; TP ranged from 2.3 to 3.6, which indicates an omnivorous diet for most populations. In addition to providing additional spatial resolution for δ13C and δ15N isoscapes in the eastern Pacific, especially in coastal habitats, this study further establishes CSIA‐AA as an effective tool to study the trophic ecology of sea turtles across a variety of food webs and habitats.

Abstract Marine mesotherms are able to occupy broader thermal niches than ectotherms; however, this means they must thermoregulate according to diverse thermal conditions across the ocean. Knowledge remains limited about how differences in thermal conditions within the selected habitats affect the behavior and associated ecological traits in mesotherms. Here, we tested if a marine mesotherm, leatherback turtles (Dermochelys coriacea) generally maintain their body temperature by diving to greater depths to expose themselves to cold waters as sea surface temperature becomes warmer. Moreover, we investigate how such behavioral thermoregulation may influence their ecological traits (e.g., foraging and migration). We analyzed 49,461 dive profiles and 16,255 temperature‐depth profiles from 17 leatherback turtles migrating across the North Pacific using satellite‐linked data loggers. Our results showed that leatherbacks changed their dive behavior regionally, in response to sea surface temperature and potential foraging habitats. Dive type classification revealed that V‐shaped, presumably gliding dives, became deeper when the surface water was warmer, likely because leatherbacks dive to deep cold waters to avoid overheating. We found five hotspots of wiggle (up‐and‐down undulations in the depth profile) dives that are indicative of foraging behavior, ranging from tropical to cool‐temperate regions in the North Pacific. The dive patterns in potential foraging hotspots indicate that leatherbacks engage in behavioral thermoregulation in warmer regions. Such bioenergetics may affect the time available for foraging activity during migration phases. In cool‐temperate foraging areas, leatherbacks are indeed able to spend more time foraging due to mesothermy. However, the trade‐off between energy gain by foraging activity and additional migration cost of moving to higher latitude areas might not result in greater reproductive output for leatherbacks foraging in distant cool‐temperate regions. These patterns highlight that mesothermy represents a trade‐off: Leatherbacks can utilize cooler waters but must engage in additional behavioral thermoregulation (i.e., extremely deep dives) in warmer waters. Thus, mesothermy might not provide a direct fitness advantage to all individual leatherback turtles; rather, it affords a species‐level fitness advantage by allowing a greater diversity of habitats to be utilized.

Abstract We assessed the effects of post‐exercise cold‐water immersion (CWI) in modulating PGC‐1α mRNA expression in response to exercise commenced with low muscle glycogen availability. In a randomized repeated‐measures design, nine recreationally active males completed an acute two‐legged high‐intensity cycling protocol (8 × 5 min at 82.5% peak power output) followed by 10 min of two‐legged post‐exercise CWI (8°C) or control conditions (CON). During each trial, one limb commenced exercise with low (LOW: