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Background: This study examined reasons not to drink in young adults in relation to demographics, alcohol use patterns, timing (weekend vs. weekday), and typical drinking motives. Methods: Young adults who reported past 30‐day alcohol use and at least one nondrinking day (n = 614; mean age = 21.5 years ±0.53) completed a survey of alcohol‐related measures (e.g., typical drinking motives) and up to 14 daily surveys that included 12 reasons not to drink assessed on nondrinking days. Multilevel logistic regressions were estimated for each reason not to drink and related covariates. Results: The most common reasons not to drink on a given day were "wasn't interested in drinking" (83.4% of nondrinking days) and "didn't want to get drunk" (81.8% of nondrinking days), with over 96% of participants endorsing each of these at least once. On days (11.6%; by 29.5% of participants) when another drug was used instead of alcohol, 81.8% used cannabis. Sex, race/ethnicity, weekend (vs. weekday), and drinking motives were differentially linked to reasons not to drink. Reporting high‐intensity drinking (i.e., ≥10 drinking on a day) versus binge (5–9 drinks on a day) in the past 2 weeks was linked to "had a hangover recently" (odds ratio = 2.85) as a reason not to drink. Conclusions: Findings suggest that reasons not to drink reflect personal decisions and highlight ways to acknowledge situational barriers (e.g., saving money for food and essentials) that can be emphasized in brief interventions. Furthermore, reasons not to drink and alcohol motives may work in tandem within the motivational model to impact alcohol use behaviors. [ABSTRACT FROM AUTHOR]

Birds are used as bioindicators of environmental mercury (Hg) contamination, and toxicity reference values are needed for injury assessments. We conducted a comprehensive review, summarized data from 168 studies, performed a series of Bayesian hierarchical meta‐analyses, and developed new toxicity reference values for the effects of methylmercury (MeHg) on birds using a benchmark dose analysis framework. Lethal and sublethal effects of MeHg on birds were categorized into nine biologically relevant endpoint categories and three age classes. Effective Hg concentrations where there was a 10% reduction (EC10) in the production of juvenile offspring (0.55 µg/g wet wt adult blood‐equivalent Hg concentrations, 80% credible interval: [0.33, 0.85]), histology endpoints (0.49 [0.15, 0.96] and 0.61 [0.09, 2.48]), and biochemical markers (0.77 [<0.25, 2.12] and 0.57 [0.35, 0.92]) were substantially lower than those for survival (2.97 [2.10, 4.73] and 5.24 [3.30, 9.55]) and behavior (6.23 [1.84, >13.42] and 3.11 [2.10, 4.64]) of juveniles and adults, respectively. Within the egg age class, survival was the most sensitive endpoint (EC10 = 2.02 µg/g wet wt adult blood‐equivalent Hg concentrations [1.39, 2.94] or 1.17 µg/g fresh wet wt egg‐equivalent Hg concentrations [0.80, 1.70]). Body morphology was not particularly sensitive to Hg. We developed toxicity reference values using a combined survival and reproduction endpoints category for juveniles, because juveniles were more sensitive to Hg toxicity than eggs or adults. Adult blood‐equivalent Hg concentrations (µg/g wet wt) and egg‐equivalent Hg concentrations (µg/g fresh wet wt) caused low injury to birds (EC1) at 0.09 [0.04, 0.17] and 0.04 [0.01, 0.08], moderate injury (EC5) at 0.6 [0.37, 0.84] and 0.3 [0.17, 0.44], high injury (EC10) at 1.3 [0.94, 1.89] and 0.7 [0.49, 1.02], and severe injury (EC20) at 3.2 [2.24, 4.78] and 1.8 [1.28, 2.79], respectively. Maternal dietary Hg (µg/g dry wt) caused low injury to juveniles at 0.16 [0.05, 0.38], moderate injury at 0.6 [0.29, 1.03], high injury at 1.1 [0.63, 1.87], and severe injury at 2.4 [1.42, 4.13]. We found few substantial differences in Hg toxicity among avian taxonomic orders, including for controlled laboratory studies that injected Hg into eggs. Our results can be used to quantify injury to birds caused by Hg pollution. Environ Toxicol Chem 2024;43:1195–1241. Published 2024. This article is a U.S. Government work and is in the public domain in the USA. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

Background: Circulating creatinine and symmetric dimethylarginine (SDMA) are biomarkers of kidney function that have been used variously to define stable vs progressive chronic kidney disease (CKD). Slope monitoring of inverse biomarker values (creatinine−1 or SDMA−1) has shown promise, but quantitative criteria to distinguish stable vs progressive CKD using this approach are lacking. Objective: Assessment of creatinine−1 and SDMA−1 slope cutoffs to distinguish stable vs progressive CKD. Animals: One hundred ten clinically healthy university staff‐owned dogs and 29 male colony dogs with progressive X‐linked hereditary nephropathy (XLHN). Methods: Retrospective analysis combining 2 prospective observational studies, 1 tracking kidney function biomarkers in healthy dogs (HDs) to a maximum of 3 years, and 1 tracking kidney function biomarkers in male colony dogs with progressive XLHN to a maximum of 1 year. The minimum slope of creatinine−1 or SDMA−1 as measured using the IDEXX SDMA test from HD was assigned as the slope cutoff for stable kidney function. Results: The stable vs progressive slope cutoff was −0.0119 week × dL/mg for creatinine−1 and −0.0007 week × dL/μg for SDMA−1. Conclusions and Clinical Importance: In the studied CKD population, progressive dysfunction can be distinguished from stable kidney function by using the slope of creatinine−1 or SDMA−1. These criteria may serve to characterize CKD in other cohorts of dogs and to establish guidelines for degrees of progression rate in dogs with naturally occurring CKD. [ABSTRACT FROM AUTHOR]

Background: Early identification of dogs with progressive vs stable chronic kidney disease (CKD) might afford opportunity for interventions that would slow progression. However, currently no surrogate biomarker reliably predicts CKD progression. Hypothesis/Objectives: Urinary cystatin B (uCysB), a novel kidney injury biomarker, predicts progressive disease in International Renal Interest Society (IRIS) CKD Stage 1. Animals: Seventy‐two dogs, including 20 dogs from 4 university centers with IRIS CKD Stage 1, with IDEXX symmetric dimethylarginine (SDMA) concentration up to 17 μg/dL and no systemic comorbidities, and 52 clinically healthy staff‐owned dogs from a fifth university center. Methods: A multicenter prospective longitudinal study was conducted between 2016 and 2021 to assess uCysB concentration in IRIS CKD Stage 1 and control dogs. Dogs were followed to a maximum of 3 years (control) or 25 months (CKD). Stage 1 IRIS CKD was classified as stable or progressive using the slope of 1/SDMA, calculated from 3 timepoints during the initial 90‐day period. Dogs with slope above or below −0.0007 week × dL/μg were classified as stable or progressive, respectively. Mixed effects modeling was used to assess the association between uCysB and progression rate. Results: Estimates of first visit uCysB results predictive of active ongoing kidney injury based on the mixed effects models were 17 ng/mL for control, 24 ng/mL for stable CKD, and 212 ng/mL for progressive CKD (P <.001). Conclusions and Clinical Importance: Urinary cystatin B differentiated stable vs progressive IRIS CKD Stage 1. Identification of dogs with progressive CKD may provide an opportunity for clinicians to intervene early and slow progression rate. [ABSTRACT FROM AUTHOR]

Background: High‐intensity drinking (HID) is associated with negative consequences, but it remains unclear whether a time qualifier (i.e., time spent drinking) is needed to identify individuals at highest risk. To improve the measurement and conceptualization of HID, we examined the utility of adding a time qualifier to define what constitutes an occasion of HID using repeated daily surveys in a sample of young adults. Methods: Participants were selected from a nationally representative sample of 12th‐grade students in the United States who participated in the Monitoring the Future (MTF) study in Spring 2018. In 2019 and 2020, young adults (at modal ages 19–20) responded to annual and daily (14 consecutive days per year) online surveys about their alcohol use. Results: When we compared moderate drinking days (less than 4/5 drinks for women/men), binge drinking days (4–7/5–9 drinks), and HID days (8+/10+ drinks), HID days had the longest duration of drinking (5.2 h), highest peak estimated blood alcohol concentration (eBAC, 0.30%), and greatest drinking pace (2.58 drinks/h). HID was associated with a greater number of negative consequences than either moderate or binge drinking; adjusting for time spent drinking did not impact this interpretation. HID was reported on 10.9% of days; when defined as 8/10+ drinks in 4 h or 2 h, HID was reported on 4.8% and 1.0% of days, respectively. Nearly all differences in eBAC and negative consequences persisted across drinking intensity despite the introduction of time constraints. Conclusions: HID days were characterized by both a longer time spent drinking and a more rapid pace of drinking. Adding a time qualifier to the definition of HID would restrict variability by only describing the minority of days and does not improve the distinctions among levels of risk. [ABSTRACT FROM AUTHOR]

Background: Cats commonly develop thyroid disease but little is known about the long‐term biological variability of serum thyroid hormone and thyrotropin (thyroid‐stimulating hormone; TSH) concentrations. Objectives: We aimed to determine the long‐term biological variation of thyroid hormones and TSH in clinically healthy cats. Methods: A prospective, observational study was carried out. Serum samples for analysis of total thyroxine (T4, by radioimmunoassay [RIA] and homogenous enzyme immunoassay [EIA]), triiodothyronine (T3), free T4 (by dialysis), and TSH were obtained every 8 weeks for 1 year from 15 healthy cats, then frozen until single‐batch analysis. Coefficients of variation (CV) within individual cats (CVI) and among individual cats (CVG), as well as the variation between duplicates (ie, analytical variation [CVA]) were determined with restricted maximum likelihood estimation. The indices of individuality (IoI) and reference change values (RCVs) for each hormone were calculated. Results: Some thyroid hormones showed similar (total T4 by EIA) or greater (TSH) interindividual relative to intraindividual variation resulting in intermediate to high IoI, consistent with previous studies evaluating the biological variation of these hormones weekly for 5–6 weeks. By contrast, total T4 (by RIA) and free T4 had a low IoI. Total T3 had a high ratio of CVA to CVI; therefore, interindividual variation could not be distinguished from analytical variation. No seasonal variability in the hormones could be demonstrated. Conclusions: Clinicians might improve the diagnosis of feline thyroid disease by establishing baseline concentrations for analytes with intermediate‐high IoI (total T4, TSH) for individual cats and applying RCVs to subsequent measurements. [ABSTRACT FROM AUTHOR]

This article examines why and how teachers of refugees enact protection by engaging with local forms of harm facing their refugee students. Through portraits of two classrooms in Jordan, we describe the relationships that form between Jordanian teachers and Syrian students, and the protection practices teachers develop in response. We propose a more comprehensive conceptualization of protection in refugee education that layers socio‐political protection on legal and rights‐based protection commonly embedded in humanitarian activities. [ABSTRACT FROM AUTHOR]

Background: Homeobox transcription factor encoding genes, genomic screen homeobox 1 and 2 (gsx1 and gsx2), are expressed during neurodevelopment in multiple vertebrates. However, we have limited knowledge of the dynamic expression of these genes through developmental time and the gene networks that they regulate in zebrafish. Results: We confirmed that gsx1 is expressed initially in the hindbrain and diencephalon and later in the optic tectum, pretectum, and cerebellar plate. gsx2 is expressed in the early telencephalon and later in the pallium and olfactory bulb. gsx1 and gsx2 are co‐expressed in the hypothalamus, preoptic area, and hindbrain, however, rarely co‐localize in the same cells. gsx1 and gsx2 mutant zebrafish were made with TALENs. gsx1 mutants exhibit stunted growth, however, they survive to adulthood and are fertile. gsx2 mutants experience swim bladder inflation failure that prevents survival. We also observed significantly reduced expression of multiple forebrain patterning distal‐less homeobox genes in mutants, and expression of foxp2 was not significantly affected. Conclusions: This work provides novel tools with which other target genes and functions of Gsx1 and Gsx2 can be characterized across the central nervous system to better understand the unique and overlapping roles of these highly conserved transcription factors. Key Findings: gsx1 and gsx2 expression is dynamic during embryonic and larval stages of neurodevelopment in zebrafish, and gsx1 expression appears to be in differentiating neurons based on their morphology and position.gsx1 and gsx2 are expressed together in several developing brain regions, however, they rarely colocalize in the same cells.Early forebrain patterning in gsx1 mutants appears normal, and Gsx1 might partially compensate for loss of Gsx2 function as more severe forebrain gene expression loss is observed in gsx1 and gsx2 mutants compared to gsx2 mutants in some instances.Complementation testing between different gsx1 or gsx2 mutant alleles shows that mutant phenotypes arise from altered gsx1 or gsx2 function. [ABSTRACT FROM AUTHOR]

Background: Biological variation helps determine whether population‐based or subject‐based reference intervals are more appropriate to assess changes in serial analytical values. Previous studies have investigated the biological variation of biochemical analytes weekly or with variable frequency over 5‐14 weeks in cats, but none have considered biological variation at less frequent intervals over 1 year. Objectives: We aimed to evaluate the long‐term biological variation of 19 biochemical analytes in clinically healthy cats. Methods: A prospective, observational study in which 15 clinically healthy, client‐owned cats were sampled for serum biochemical analyses every 8 weeks for 1 year. Frozen serum samples were single‐batch analyzed. Restricted maximum likelihood estimation was used to determine the coefficients of variation (CV), describing variation within each cat, between cats, and the analytical variation. These CVs were used to determine the indices of individuality and reference change values (RCVs). Results: Albumin, alkaline phosphatase, creatine kinase, and globulin had high indices of individuality, indicating that they are best evaluated by RCVs. Phosphorus, potassium, chloride, sodium, symmetric dimethylarginine, and total CO2 had low indices of individuality, indicating that population‐based reference intervals are appropriate. Alanine aminotransferase, aspartate aminotransferase, blood urea nitrogen, calcium, cholesterol, creatinine, glucose, total bilirubin, and total protein had intermediate indices of individuality, indicating that RCVs may provide additional insight into the interpretation of analyte measurements beyond the population‐based reference intervals. Conclusions: For many analytes, the biological variation detected was similar to that reported in prior studies. Clinicians should consider the biological variation of analytes to best interpret clinically relevant changes in serial analyte measurements. [ABSTRACT FROM AUTHOR]

Objective: To assess the occurrence of acute kidney injury (AKI) in dogs undergoing cardiac surgery under cardiopulmonary bypass (CPB) and explore associations between traditional and novel serum and urinary biomarkers. Design: Prospective cohort study conducted between July 2018 and April 2019. Setting: University teaching hospital. Animals: Nineteen dogs undergoing cardiac surgery under CPB with preoperative serum creatinine <140 μmol/L (<1.6mg/dl). Interventions: Blood and urine samples were obtained at 4 time points: preoperatively following general anesthesia induction, immediately postoperatively, and 2 and 4 days postoperatively (T1, T2, T3, and T4). AKI was defined as an increase in serum creatinine ≥26.4 μmol/L (≥0.3 mg/dl) above baseline within 48 hours. Serum creatinine, C-reactive protein (CRP), symmetric dimethylarginine (SDMA), inosine, beta-aminoisobutyric acid (BAIB), urinary clusterin (uClus), and urinary cystatin B (uCysB) were measured. Data were log-transformed (log10) when appropriate and assessed using linearmixed-effects models. Measurements and Main Results: AKI occurred in 3 of 19 dogs (15.8%, 95% confidence interval: 0.047-0.384). Inosine increased at T2 (adjusted mean ± standard error: 53 ± 5.6) in all dogs, and then gradually decreased. Log10uCysB increased at T2 (2.3 ± 0.1) in all dogs and remained high. Log10CRP and log10uClus increased significantly at T3 (1.9 ± 0.1 and 3.6 ± 0.1, respectively) in all dogs and remained increased. There was a significant positive association between serum creatinine and SDMA (P < 0.001, estimate ± standard error: 0.06 ± 0.00), between log10CRP and log10uClus (P < 0.001, 0.35 ± 0.08), between SDMA and creatinine as well as between SDMA and BAIB (P < 0.001, 11.1 ± 0.83 and P < 0.001, 1.06 ± 0.22, respectively) for all dogs at all time points. Conclusions: Inosine and uCysB concentrations changed in all dogs immediately following a surgery under CPB and may indicate tubular injury. Further studies are required to ascertain the usefulness of those biomarkers in early detection of AKI. [ABSTRACT FROM AUTHOR]

Nest predation is the main cause of nest failure for ducks. Understanding how habitat features influence predator movements may facilitate management of upland and wetland breeding habitats that reduces predator encounter rates with duck nests and increases nest survival rates. For 1618 duck nests, nest survival increased with distance to phragmites (Phragmites australis), shrubs, telephone poles, human structures, and canals, but not for four other habitat features. Using GPS collars, we tracked 25 raccoons (Procyon lotor) and 16 striped skunks (Mephitis mephitis) over 4 years during waterfowl breeding and found marked differences in how these predators were located relative to specific habitat features; moreover, the probability of duck nests being encountered by predators differed by species. Specifically, proximity to canals, wetlands, trees, levees/roads, human structures, shrubs, and telephone poles increased the likelihood of a nest being encountered by collared raccoons. For collared skunks, nests were more likely to be encountered if they were closer to canals, trees, and shrubs, and farther from wetlands and human structures. Most predator encounters with duck nests were attributable to a few individuals; 29.2% of raccoons and 38.5% of skunks were responsible for 95.6% of total nest encounters. During the central span of duck nesting (April 17–June 14: 58 nights), these seven raccoons and five skunks encountered >1 nest on 50.8 ± 29.2% (mean ± SD) and 41.5 ± 28.3% of nights, respectively, and of those nights individual raccoons and skunks averaged 2.60 ± 1.28 and 2.50 ± 1.09 nest encounters/night, respectively. For collared predators that encountered >1 nest, a higher proportion of nests encountered by skunks had evidence of predation (51.9 ± 26.6%) compared to nests encountered by raccoons (22.3 ± 17.1%). Because duck eggs were most likely consumed as raccoons and skunks opportunistically discovered nests, managing the habitat features those predators most strongly associated with could potentially reduce rates of egg predation. [ABSTRACT FROM AUTHOR]

Incubating birds must balance the needs of their developing embryos with their own physiological needs, and many birds accomplish this by taking periodic breaks from incubation. Mallard (Anas platyrhynchos) and gadwall (Mareca strepera) hens typically take incubation recesses in the early morning and late afternoon, but recesses can also take place at night. We examined nocturnal incubation recess behavior for mallard and gadwall hens nesting in Suisun Marsh, California, USA, using iButton temperature dataloggers and continuous video monitoring at nests. Fourteen percent of all detected incubation recesses (N = 13,708) were nocturnal and took place on 20% of nest‐days (N = 8,668). Video monitoring showed that hens covered their eggs with down feathers when they initiated a nocturnal recess themselves as they would a diurnal recess, but they left the eggs uncovered in 94% of the nocturnal recesses in which predators appeared at nests. Thus, determining whether or not eggs were left uncovered during a recess can provide strong indication whether the recess was initiated by the hen (eggs covered) or a predator (eggs uncovered). Because nest temperature decreased more rapidly when eggs were left uncovered versus covered, we were able to characterize eggs during nocturnal incubation recesses as covered or uncovered using nest temperature data. Overall, we predicted that 75% of nocturnal recesses were hen‐initiated recesses (eggs covered) whereas 25% of nocturnal recesses were predator‐initiated recesses (eggs uncovered). Of the predator‐initiated nocturnal recesses, 56% were accompanied by evidence of depredation at the nest during the subsequent nest monitoring visit. Hen‐initiated nocturnal recesses began later in the night (closer to morning) and were shorter than predator‐initiated nocturnal recesses. Our results indicate that nocturnal incubation recesses occur regularly (14% of all recesses) and, similar to diurnal recesses, most nocturnal recesses (75%) are initiated by the hen rather than an approaching predator. [ABSTRACT FROM AUTHOR]

Background: Detection of urinary casts is difficult due to their intermittent presence and deterioration in urine samples. Objective: To compare the performance of the IDEXX SediVue Dx® Urine Sediment Analyzer (SediVue) with manual microscopy for the detection of urinary casts. We hypothesized that the SediVue analyzer would perform similarly to manual microscopy in cast detection. Animals Four hundred forty‐three samples from 420 dogs from a hospital population. Methods: This is a prospective, cross‐sectional study. For SediVue analysis (software version [SW] 1.0.1.3), uncentrifuged urine was pipetted into a disposable cartridge. Seventy images were captured and processed by an onboard algorithm. For manual microscopy, urine was centrifuged to obtain sediment. Any cast identified by either method was considered a positive result (>0/low‐power field [LPF]). SediVue images were evaluated if casts were detected by either methodology. A revised sensitivity and specificity were calculated after image review and when using a threshold of >1 cast/LPF. Results: The sensitivity of the SediVue analysis for the detection of urinary casts was 53.7% (43.85%‐63.35%), and specificity was 86.0% (81.78%‐89.51%). After image review, the revised sensitivity/specificity was 52.0% (42.89%‐61.02%) and 90.6% (86.81%‐93.54%), respectively. When using a more clinically relevant threshold of >1/LPF, the sensitivity was 52.6% (35.82%‐69.02%) and specificity was 99.3% (97.85%‐99.85%). Conclusions and Clinical Importance: The SediVue provides moderate agreement to manual methodology for detection of casts in urine. [ABSTRACT FROM AUTHOR]

Nesting birds must provide a thermal environment sufficient for egg development while also meeting self‐maintenance needs. Many birds, particularly those with uniparental incubation, achieve this balance through periodic incubation recesses, during which foraging and other self‐maintenance activities can occur. However, incubating birds may experience disturbances such as predator or human activity which interrupt natural incubation patterns by compelling them to leave the nest. We characterized incubating mallard Anas platyrhynchos and gadwall Mareca strepera hens' responses when flushed by predators and investigators in Suisun Marsh, California, USA. Diurnal incubation recesses initiated by investigators approaching nests were 63% longer than natural diurnal incubation recesses initiated by the hen (geometric mean: 226.77 min versus 142.04 min). Nocturnal incubation recesses, many of which were likely the result of predators flushing hens, were of similar duration regardless of whether the nest was partially depredated during the event (115.33 [101.01;131.68] minutes) or not (119.62 [111.96;127.82] minutes), yet were 16% shorter than natural diurnal incubation recesses. Hens moved further from the nest during natural diurnal recesses or investigator‐initiated recesses than during nocturnal recesses, and the proportion of hen locations recorded in wetland versus upland habitat during recesses varied with recess type (model‐predicted means: natural diurnal recess 0.77; investigator‐initiated recess 0.82; nocturnal recess 0.31). Hens were more likely to take a natural recess following an investigator‐initiated recess earlier that same day than following a natural recess earlier that same day, and natural recesses that followed an investigator‐initiated recess were longer than natural recesses that followed an earlier natural recess, suggesting that hens may not fulfill all of their physiological needs during investigator‐initiated recesses. We found no evidence that the duration of investigator‐initiated recesses was influenced by repeated visits to the nest, whether by predators or by investigators, and trapping and handling the hen did not affect investigator‐initiated recess duration unless the hen was also fitted with a backpack‐harness style GPS–GSM transmitter at the time of capture. Hens that were captured and fitted with GPS–GSM transmitters took recesses that were 26% longer than recesses during which a hen was captured but a GPS–GSM transmitter was not attached. Incubation interruptions had measurable but limited and specific effects on hen behavior. [ABSTRACT FROM AUTHOR]

Background: Converting nutrition support to energy results in mitochondrial free radical production, possibly increasing oxidative stress. Highly prevalent single nucleotide variants (SNV) exist for the genes encoding antioxidant enzymes responsible for the detoxification of reactive oxygen species. Our objective was to explore the interaction between nutrition support and genetic SNV's for two anti‐oxidant proteins (rs4880 SNV for manganese superoxide dismutase and rs1050450 SNV for glutathione peroxidase 1) on oxidative stress and secondarily on intensive care unit (ICU) mortality. Methods: We performed a post‐hoc analysis on 34 mechanically ventilated sepsis patients from a randomized control feeding trial. Participants were dichotomized into those who carried both the rs4880 and the rs1050450 at‐risk alleles (Risk Group) versus all others (Nonrisk Group). We explored the interaction between genotype and percent time spent in the upper median of energy exposure on oxidative stress and ICU mortality. Results: Adjusting for confounders, the slope of log F2‐isoprostane levels across percentage of days spent in the upper median of daily kilocalories per kilogram (kcal/kg) was 0.01 higher in the Risk Group compared to the Non‐Risk Group (p=0.01). Every 1 percent increase in days spent in the upper median of daily kcal/kg was associated with an adjusted 10.3 percent increased odds of ICU mortality amongst participants in the Risk Group (odds ratio [OR]=1.103, p=0.06) but was highly insignificant in the Nonrisk group (OR=0.991, P=0.79). Conclusion: Nutrition support may lead to increased oxidative stress and worse clinical outcomes in a large percent of ICU patients with an at‐risk genotype. [ABSTRACT FROM AUTHOR]

Background: Prospective randomized controlled trials (PRCTs) that found harm in patients receiving higher levels of energy exposure have been largely ignored, in part because of the lack of a known mechanism of harm. Objective: The current 7‐day pilot study is a PRCT and post hoc analysis designed to explore the relationship between energy exposure and oxidative stress (as plasma total F2‐isoprostanes) in mechanically ventilated intensive care unit patients with systemic inflammatory response syndrome. Methods: Thirty‐five participants were randomized to receive either 100% or 40% of their estimated energy needs. Our intent‐to‐treat model found no differences in F2‐isoprostanes between groups. A post hoc analysis revealed that on days when participants were in the highest tertile of daily kcal/kg, the real‐time energy flow rate within 2 hours of the blood draw was predictive of increased oxidative stress. On these days, participants in the second or third vs the first tertile of real‐time energy flow rate experienced a 41.8% (P =.006) or 26.5% (P =.001) increase in F2‐isoprostane levels, respectively. This was confirmed through a within‐group subanalysis restricted to participants with measurements on both sides of the median of real‐time energy flow rate that found a 28.2% F2‐isoprostane increase on days in the upper vs lower median of flow rate (P =.002). Conclusion: The benefits of feeding may be more nuanced than previously suspected. Our findings imply a potential mechanism of harm in meeting the current recommendations for nutrition support in the critically ill that warrants further investigation. [ABSTRACT FROM AUTHOR]

Eggshell thickness is important for physiological, ecological, and ecotoxicological studies on birds; however, empirical eggshell thickness measurements for many species and regions are limited. We measured eggshell thickness at the equator and the egg poles for 12 avian species and related eggshell thickness to egg morphometrics, embryonic development, egg status, and mercury contamination. Within an egg, eggshells were approximately 5.1% thicker at the equator than the sharp pole of the egg, although this difference varied among species (0.6%-9.8%). Within Forster's tern (Sterna forsteri), where eggshell thickness was measured at 5 equally spaced positions along the longitude of the egg, eggshell thickness changed more rapidly near the sharp pole of the egg compared to near the blunt pole of the egg. Within species, eggshell thickness was related to egg width and egg volume for six of the 12 species but was not related to egg length for any species. Among species, mean eggshell thickness was strongly related to species mean egg width, egg length, egg volume, and bird body mass, although species mean body mass was the strongest predictor of species mean eggshell thickness. Using three species (American avocet [Recurvirostra americana], black-necked stilt [Himantopus mexicanus], and Forster's tern), whose nests were carefully monitored, eggshell thickness (including the eggshell membrane) did not differ among viable, naturally abandoned, dead, or failed-tohatch eggs; was not related to total mercury concentrations of the egg content; and did not decrease with embryonic age. Our study also provides a review of all existing eggshell thickness data for these 12 species. [ABSTRACT FROM AUTHOR]

Background: Minimal information is available to validate measurement of respiratory muscle strength (RMS) in the clinical setting. The purpose of this study was to determine the correlation between maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), and sniff nasal inspiratory pressure (SNIP) with handgrip strength (HGS) and cross sectional muscle area obtained via diagnostic abdominal computed tomography (CT).Materials and Methods: Measures of MIP, MEP, SNIP, and HGS were obtained from individuals that participated in a previously published study; individuals who had an abdominal CT completed with (±)7 days of obtaining RMS measures were included. Both RMS and HGS were measured within 48-72 hours of admission; for RMS, the highest absolute (cm H2 O) and percent predicted values were recorded, and the average of 3 HGS measurements (kg) was documented. Cross-sectional muscle area (cm2 ) at the third lumbar region was recorded. Spearman's correlation coefficient was used to assess the relationship between variables.Results: A total of 35 participants were included. HGS was correlated to absolute MIP (rs = 0.62, rs = 0.61), MEP (rs = 0.74, rs = 0.73), and SNIP (rs = 0.58, rs = 0.54) for males and females, respectively. Crosss-sectional muscle area was correlated with absolute MIP (rs = 0.66), MEP (rs = 0.58), and SNIP (rs = 0.783) for men and absolute SNIP (rs = 0.56) among women.Conclusion: Measures of RMS represent a promising assessment of muscle mass and function among hospitalized patients. [ABSTRACT FROM AUTHOR]

Radio‐telemetry is a commonly used scientific technique that allows researchers to collect detailed movement, habitat use, and survival data of animals; however, evidence indicates that using telemetry can affect behavior and survival. Using multiple breeding colonies and years, we investigated the effects of attached radio‐transmitters on growth and survival of Forster's tern (Sterna forsteri) chicks in San Francisco Bay, California, USA, 2010–2011. We tested these potential effects at isolated islands that allowed for high re‐capture rates (typically >85%) in radio‐marked and banded‐only chicks. Modeled Gompertz growth curves suggested that transmitters had a small negative effect on some of the asymptotic growth parameters of tern chicks; tarsus (−1.5 ± 0.7% [SE]), culmen (−1.7 ± 1.2%), and wing (−4.9 ± 2.0%) lengths were shorter for radio‐marked chicks compared to banded‐only chicks. In contrast, there was no difference in asymptotic mass between radio‐marked chicks and banded‐only chicks. Survival from hatching to fledging was lower for radio‐marked chicks than banded‐only chicks during 2010 (banded‐only = 0.313 ± 0.162 vs. radio‐marked = 0.250 ± 0.165) and 2011 (0.193 ± 0.030 vs. 0.123 ± 0.027). Most of the transmitter effect occurred within the first week after hatching, rather than in older chicks. Notably, the effect of transmitters on chick survival was primarily additive, indicating that the effect of transmitters on radio‐marked chicks was not influenced by other ecological covariates. Given the effect radio‐transmitters had on survival did not change across temporal or ecological gradients, transmitters can still be used to evaluate ecological factors affecting survival and timing of mortality and radio‐marked birds can be used to make inferences to the general population. Published 2020. This article is a U.S. Government work and is in the public domain in the USA. Radio‐transmitters affected the growth and survival of Forster's tern chicks. The transmitter effect on survival was additive, indicating that although estimates of survival of radio‐marked chicks may be lower relative to survival rates of banded‐only chicks, the relationships with ecological covariates still reflected the true relationships that would have been observed on banded‐only chicks. [ABSTRACT FROM AUTHOR]

This study examines how students of majority and minority ethnic backgrounds in Botswana understand national identity as inclusive of their ethnic groups. Within assimilationist policies and curriculum, we find that the value of national identity rests on its positioning as a path toward higher levels of education and employment. However, for ethnic minority students, enacting this national identity requires sacrifice of other desired dimensions of a future good life, including ethnic identity. [ABSTRACT FROM AUTHOR]

Background and Aims: To determine whether transdiagnostic risk, represented as elevations in one high‐risk personality trait, interacts with behavior‐specific risk, represented as elevated expectancies for reinforcement from either drinking or smoking, to account partly for early adolescent drinking and smoking behavior. Design Multiple regression analysis. Setting: Twenty‐three public schools in two school systems in the United States. Participants: A sample of 1897 adolescents tested in the spring of 5th, 6th, 7th, 8th and 9th grades. Measurements Transdiagnostic risk was measured as negative urgency, the tendency to act rashly when distressed, using the UPPS‐P child version. Drinking‐specific and smoking‐specific risk were measured as expectancies for reinforcement from drinking and smoking, using the Memory Model‐Based Expectancy Questionnaire (alcohol) and the Adolescent Smoking Consequences Questionnaire (smoking). Findings There was consistent concurrent prediction from the interactions of (a) negative urgency and alcohol reinforcement expectancies to early adolescent drinking and (b) negative urgency and smoking reinforcement expectancies to early adolescent smoking, above and beyond prediction from the main effects of those variables. In each case, expectancies were more predictive at higher levels of negative urgency. Incremental R2 values for main effects ranged from 0.07 to 0.26, and for interactions ranged from 0.01 to 0.03. Prospectively, the main effects predicted subsequent behavior but the interaction effects did not, except in one case. Conclusions: Among elementary and high school students in the United States, the joint effects of negative urgency and behavior‐specific expectancies help to explain drinking and smoking behavior. Joint elevations on the trait and the learning variable account for drinking and smoking behavior beyond the main effects of each predictor. However, there is reason to doubt whether the joint effects predict subsequent increases in drinking and smoking beyond the main effects of those variables. [ABSTRACT FROM AUTHOR]

Feathers are widely used to represent mercury contamination in birds. Yet, few recommendations exist that provide guidance for using bird feathers in mercury monitoring programs. We conducted a literature review and 5 experiments to show that mercury concentrations vary substantially within (vane >100% higher than calamus) and among (>1000%) individual feathers from the same bird. We developed a research tool and guidelines for using bird feathers for mercury studies based on 3 components: 1) variability of feather mercury concentrations within an individual bird (coefficient of variation), 2) desired accuracy of the measured mercury concentration, and 3) feather and bird mass. Our results suggest a general rule that if the goal is to limit analytical and processing costs by using whole feathers in only one sample boat, then to achieve an accuracy within 10% of a bird's overall average feather mercury concentration a bird with a coefficient of variation ≤10% must be <190 g (size of a large shorebird). To achieve an accuracy within 20%, a bird with a coefficient of variation ≤10% must be <920 g (a large duck). When more than one sample boat is needed to fit the required number of feathers to achieve the desired accuracy, the results suggest homogenizing feathers and analyzing an aliquot of ≥20 mg for mercury. The present study suggests increasing the number of feathers typically used per bird to assess mercury concentrations. Environ Toxicol Chem 2019;38:1164–1187. Published 2019 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America. [ABSTRACT FROM AUTHOR]

For ground‐nesting waterfowl, the timing of egg hatch and duckling departure from the nest may be influenced by the risk of predation at the nest and en route to wetlands and constrained by the time required for ducklings to imprint on the hen and be physically able to leave the nest. We determined the timing of hatch, nest departure, and predation on dabbling duck broods using small video cameras placed at the nests of mallard (Anas platyrhynchos; n = 26), gadwall (Mareca strepera; n = 24), and cinnamon teal (Anas cyanoptera; n = 5). Mallard eggs began to hatch throughout the day and night, whereas gadwall eggs generally started to hatch during daylight hours (mean 7.5 hr after dawn). Among all species, duckling departure from the nest occurred during daylight (98%), and 53% of hens typically left the nest with their broods 1–4 hr after dawn. For mallard and gadwall, we identified three strategies for the timing of nest departure: (a) 9% of broods left the nest the same day that eggs began to hatch (6–12 hr later), (b) 81% of broods left the nest the day after eggs began to hatch, and (c) 10% of broods waited 2 days to depart the nest after eggs began to hatch, leaving the nest just after the second dawn (27–42 hr later). Overall, eggs were depredated at 10% of nests with cameras in the 2 days prior to hatch and ducklings were depredated at 15% of nests with cameras before leaving the nest. Our results suggest that broods prefer to depart the nest early in the morning, which may best balance developmental constraints with predation risk both at the nest and en route to wetlands. [ABSTRACT FROM AUTHOR]

The article discusses how nitrogen and carbon stable-isotope ratios change in adult northern elephant seals during the breeding and molting fasts. It notes that the physiological processes associated with fasting and lactation can individually alter N and C stable isotopes in a variety of taxa, including birds and mammals. It adds that the rate of proportional mass loss for males is slower than females over the breeding season.

ABSTRACT: Depredation plays an important role in determining duck nest success and predator and female duck behavior during nest depredation can influence nest fate. We examined depredation of mallard (Anas platyrhynchos) and gadwall (A. strepera) nests in Suisun Marsh, California, USA, in 2015–2016 with continuous infrared video monitoring to identify nest predators and characterize predator and female duck behavior during depredation events. We recorded predators at 44% of 147 nests monitored. Raccoons (Procyon lotor) were the most frequent predator observed at nests (40% of nests visited and 53% of depredated eggs) followed by striped skunks (Mephitis mephitis; 27% and 27%), coyotes (Canis latrans; 4% and 9%), common ravens (Corvus corax; 4% and 9%), gopher snakes (Pituophis catenifer catenifer; 19% and 0%), and western yellow‐bellied racers (Coluber constrictor mormon; 1% and 0%). The number of eggs depredated per depredation bout varied among predators (raccoons: 7.3 eggs; skunks: 2.5; coyotes: 7.4; ravens: 7.7; and snakes: 0.0). Mammal depredation occurred between 1600 and 0400, whereas snakes and ravens were observed at nests during the day (snakes: 1000–2100; ravens: 1700). Females flushed from nests immediately before predator arrival ( x ¯ = 29.0 ± 16.6 [SD] sec), and this timing did not vary among predators. However, the length of nest depredation bouts varied among predators. Nest visits by gopher snakes were longer (18.6 ± 19.4 min) than depredation bouts by other predators (12.3 ± 10.7 min), but snakes did not successfully consume any eggs. Females took more time to return to nests when nests were depredated by raccoons (239 ± 137 min), whereas females returned more quickly when nests were visited by skunks (81 ± 163 min) or gopher snakes (15 ± 128 min). Partial clutch depredation occurred at 15% of depredated nests, but only 23% of partially depredated nests successfully hatched ≥1 egg. Our results indicate that predator type and behavior can influence female behavior and nest fate, and that management actions that reduce the effectiveness of raccoons and skunks encountering waterfowl nests may benefit these nesting populations. Published 2018. This article is a U.S. Government work and is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

Background: The Intensive Nutrition in Acute Lung Injury: Clinical Trial (INTACT), designed to evaluate outcomes of calorie delivery from acute respiratory distress syndrome (ARDS) diagnosis through hospital discharge, was stopped due to higher mortality in the intervention group. Post hoc analysis found timing and dose of calorie delivery influenced mortality. The objective of this retrospective cohort study was to determine if early vs late calorie exposure changed the hazard of death among a larger sample of patients with ARDS.Methods: Adult patients who met the eligibility criteria for INTACT but did not participate were included. Daily calorie delivery was collected from the date INTACT eligibility was determined to extubation or death. Cox proportional hazards regression was used to model the relationship between hazard of hospital death with average calorie exposure received over increasing study days and after day 7.Results: A total of 298 patients were included; overall mortality was 33%. Among patients who remained intubated at 1 week (n = 202), higher kcal/kg received from intensive care unit (ICU) days 1-6 increased hazards of subsequent death on days 7+ (hazard ratio [HR], 1.04; 95% confidence interval [CI], 1.01-1.06); kcal/kg received after ICU day 7 decreased the hazards of death on day 7+ (HR, 0.53; 95% CI, 0.33-0.84).Conclusions: Higher calorie exposure between ICU days 1 and 7 was associated with higher subsequent hazard of mortality, and provision of high-calorie exposure after day 8 decreased the hazards of death. [ABSTRACT FROM AUTHOR]

Abstract: Intraspecific variability in foraging behavior has been documented across a range of taxonomic groups, yet the energetic consequences of this variation are not well understood for many species. Understanding the effect of behavioral variation on energy expenditure and acquisition is particularly crucial for mammalian carnivores because they have high energy requirements that place considerable pressure on prey populations. To determine the influence of behavior on energy expenditure and balance, we combined simultaneous measurements of at‐sea field metabolic rate (FMR) and foraging behavior in a marine carnivore that exhibits intraspecific behavioral variation, the California sea lion (Zalophus californianus). Sea lions exhibited variability in at‐sea FMR, with some individuals expending energy at a maximum of twice the rate of others. This variation was in part attributable to differences in diving behavior that may have been reflective of diet; however, this was only true for sea lions using a foraging strategy consisting of epipelagic (<200 m within the water column) and benthic dives. In contrast, sea lions that used a deep‐diving foraging strategy all had similar values of at‐sea FMR that were unrelated to diving behavior. Energy intake did not differ between foraging strategies and was unrelated to energy expenditure. Our findings suggest that energy expenditure in California sea lions may be influenced by interactions between diet and oxygen conservation strategies. There were no apparent energetic trade‐offs between foraging strategies, although there was preliminary evidence that foraging strategies may differ in their variability in energy balance. The energetic consequences of behavioral variation may influence the reproductive success of female sea lions and result in differential impacts of individuals on prey populations. These findings highlight the importance of quantifying the relationships between energy expenditure and foraging behavior in other carnivores for studies addressing fundamental and applied physiological and ecological questions. [ABSTRACT FROM AUTHOR]

Background and aims Among US high school students, alcohol consumption and cigarette smoking are associated with numerous concurrent and future harms. We tested whether multiple elementary school personality dispositions to behave impulsively can predict these addictive behaviors invariably across gender and race. Design and Setting This longitudinal design involved testing whether individual differences on impulsigenic traits in elementary school predicted drinking and smoking 4 years later in high school in 23 public schools in Kentucky, USA. Participants A total of 1897 youth, mean age 10.33 at wave 1, drawn from urban, rural and suburban backgrounds. Measurements Drinking and smoking frequency were assessed by single-item questions. The key predictors were impulsigenic traits measured with the UPPS-P Child Version impulsive behavior scale. Important covariates included were pubertal status, depression, negative affect and positive affect; each was assessed by self-report. Findings Three personality traits measured in 5th grade, each representing different dispositions to engage in impulsive behavior, predicted drinking and smoking in 9th grade above and beyond other risk factors and 5th grade drinking and smoking. Specifically, urgency ( b = 0.10, 0.13), sensation-seeking ( b = 0.13, 0.07) and low conscientiousness ( b = 0.14, 0.11) each uniquely predicted both high school drinking and smoking, respectively. There was no evidence that any trait predicted either outcome more strongly than the other traits, nor was there evidence that predictive results varied by gender or race. Conclusions Three personality traits (urgency, sensation-seeking and low conscientiousness), when measured in 11-year-old children, predict those children's drinking and smoking behavior individually at age 15. The effects are invariant across gender and race. [ABSTRACT FROM AUTHOR]

Eggshells are a potential tool for nonlethally sampling contaminant concentrations in bird eggs, yet few studies have examined their utility to represent mercury exposure. We assessed mercury concentrations in eggshell components for 23 bird species and determined whether they correlated with total mercury (THg) in egg contents. We designed a multi-experiment analysis to examine how THg is partitioned into eggshell components, specifically hardened eggshells, material adhered to the eggshells, and inner eggshell membranes. The THg concentrations in eggshells were much lower than in egg contents, and almost all of the THg within the eggshell was contained within material adhered to eggshells and inner eggshell membranes, and specifically not within calcium-rich hardened eggshells. Despite very little mercury in hardened eggshells, THg concentrations in hardened eggshells had the strongest correlation with egg contents among all eggshell components. However, species with the same THg concentrations in eggshells had different THg concentrations in egg contents, indicating that there is no global predictive equation among species for the relationship between eggshell and egg content THg concentrations. Furthermore, for all species, THg concentrations in eggshells decreased with relative embryo age. Although the majority of mercury in eggshells was contained within other eggshell components and not within hardened eggshells, THg in hardened eggshells can be used to estimate THg concentrations in egg contents, if embryo age and species are addressed. Environ Toxicol Chem 2017;36:2417-2427. Published 2017 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America. [ABSTRACT FROM AUTHOR]

Background: In critically ill patients, muscle loss is associated with adverse outcomes. Raw bioelectrical impedance analysis (BIA) parameters (eg, phase angle [PA] and impedance ratio [IR]) have received attention as potential markers of muscularity, nutrition status, and clinical outcomes. Our objective was to test whether PA and IR could be used to assess low muscularity and predict clinical outcomes.Methods: Patients (≥18 years) having an abdominal computed tomography (CT) scan and admitted to intensive care underwent multifrequency BIA within 72 hours of scan. CT scans were landmarked at the third lumbar vertebra and analyzed for skeletal muscle cross-sectional area (CSA). CSA ≤170 cm2 for males and ≤110 cm2 for females defined low muscularity. The relationship between PA (and IR) and CT muscle CSA was evaluated using multivariate regression and included adjustments for age, sex, body mass index, Charlson Comorbidity Index, and admission type. PA and IR were also evaluated for predicting discharge status using dual-energy x-ray absorptiometry-derived cut-points for low fat-free mass index.Results: Of 171 potentially eligible patients, 71 had BIA and CT scans within 72 hours. Area under the receiver operating characteristic (c-index) curve to predict CT-defined low muscularity was 0.67 ( P ≤ .05) for both PA and IR. With covariates added to logistic regression models, PA and IR c-indexes were 0.78 and 0.76 ( P < .05), respectively. Low PA and high IR predicted time to live ICU discharge.Conclusion: Our study highlights the potential utility of PA and IR as markers to identify patients with low muscularity who may benefit from early and rigorous intervention. [ABSTRACT FROM AUTHOR]

Little is known about the foraging behavior of top predators in the deep mesopelagic ocean. Elephant seals dive to the deep biota-poor oxygen minimum zone ( OMZ) (>800 m depth) despite high diving costs in terms of energy and time, but how they successfully forage in the OMZ remains largely unknown. Assessment of their feeding rate is the key to understanding their foraging behavior, but this has been challenging. Here, we assessed the feeding rate of 14 female northern elephant seals determined by jaw motion events ( JME) and dive cycle time to examine how feeding rates varied with dive depth, particularly in the OMZ. We also obtained video footage from seal-mounted videos to understand their feeding in the OMZ. While the diel vertical migration pattern was apparent for most depths of the JME, some very deep dives, beyond the normal diel depth ranges, occurred episodically during daylight hours. The midmesopelagic zone was the main foraging zone for all seals. Larger seals tended to show smaller numbers of JME and lower feeding rates than smaller seals during migration, suggesting that larger seals tended to feed on larger prey to satisfy their metabolic needs. Larger seals also dived frequently to the deep OMZ, possibly because of a greater diving ability than smaller seals, suggesting their dependency on food in the deeper depth zones. Video observations showed that seals encountered the rarely reported ragfish ( Icosteus aenigmaticus) in the depths of the OMZ, which failed to show an escape response from the seals, suggesting that low oxygen concentrations might reduce prey mobility. Less mobile prey in OMZ would enhance the efficiency of foraging in this zone, especially for large seals that can dive deeper and longer. We suggest that the OMZ plays an important role in structuring the mesopelagic ecosystem and for the survival and evolution of elephant seals. [ABSTRACT FROM AUTHOR]

Foraging theory predicts that predators adjust their movements according to the spatial distribution of prey. Since prey is often patchily distributed, area-restricted search ( ARS) behaviour, characterized by sinuous search paths of predators with increased turning frequency, should be effective in foraging., However, it remains unclear whether ARS behaviour actually enhances foraging success in free-ranging animals, especially in marine animals that forage in a three-dimensional (3D) environment., Here, we reconstructed 3D dive paths of a highly pelagic marine predator, the northern elephant seal ( n = 3), with multisensor data loggers that recorded depth, tri-axis acceleration, tri-axis magnetism and swim speed. We identified spatial scales of volume-restricted search ( VRS, termed for 3D ARS) behaviour using spherical first-passage time analysis on 3D dive paths, accompanied with quantifying feeding rates in VRS by using mandible accelerometers that recorded feeding events., Seals exhibited VRS behaviour at two spatial scales (radius of spheres): small- VRS (8-10 m) and large- VRS (17-19 m). Most feeding events occurred in VRS zones (78 and 86% for small and large- VRS, respectively), although VRS accounted for a small proportion of bottom phase of dives in distance travelled. This suggests a strong link between VRS behaviour and foraging success., There was a hierarchical structure to the VRS; most small- VRS (95%) were nested within large- VRS (i.e. nested VRS). Importantly, nested VRS had significantly higher feeding rates than non-nested VRS, because nested VRS contained small- and large- VRS with higher and lower feeding rates, respectively. These results suggest that seals forage on mesopelagic prey in a hierarchical patch system where high-density patches at small scales are nested within low-density patches at larger scales., We demonstrated that seals employed scale-dependent, hierarchical 3D movements and that underwater fine-scale sinuous movements (i.e. VRS) were strongly linked to higher foraging success, particularly within nested VRS zones. We suggest that seals enhanced foraging success by employing hierarchical movements that possibly reflect the hierarchical property of prey distribution. Although recent studies advocate that optimal searching behaviour would be scale-independent (e.g. Lévy walk), our study suggests that scale-dependent processes are important components of successful foraging behaviour. [ABSTRACT FROM AUTHOR]

Mercury (Hg) biomonitoring and toxicological risk assessments for marine mammals commonly sample different tissues, making comparisons with toxicity benchmarks and among species and regions difficult. Few studies have examined how life-history events, such as fasting, influence the relationship between total Hg (THg) concentrations in different tissues. The authors evaluated the relationships between THg concentrations in blood, muscle, and hair of female and male northern elephant seals ( Mirounga angustirostris) at the start and end of the breeding and molting fasts. The relationships between tissues varied among tissue pairs and differed by sampling period and sex. Blood and muscle were generally related at all time periods; however, hair, an inert tissue, did not strongly represent the metabolically active tissues (blood and muscle) at all times of year. The strongest relationships between THg concentrations in hair and those in blood or muscle were observed during periods of active hair growth (end of the molting period) or during time periods when internal body conditions were similar to those when the hair was grown (end of the breeding fast). The results indicate that THg concentrations in blood or muscle can be translated to the other tissue type using the equations developed but that THg concentrations in hair were generally a poor index of internal THg concentrations except during the end of fasting periods. Environ Toxicol Chem 2016;35:2103-2110. © 2016 SETAC [ABSTRACT FROM AUTHOR]

We thank Drs. Patel, Martindale, and Heyland1 for their interest in our most recent study2 exploring the role of early exposure to recommended energy delivery in critically ill patients with acute respiratory distress syndrome. Their stated concerns center around 3 major areas: (1) the comparability of the population in our study2 with those of INTACT (Intensive Nutrition in Acute Lung Injury: A Clinical Trial); (2) their confusion on the analysis of the relationship between the likelihood of death with energy exposure (table 1 in our article2 ); and (3) their apparent misunderstanding of type I error, type II error, P-values, and power analysis. Our responses to each of these areas are detailed as follows. [ABSTRACT FROM AUTHOR]

RATIONALE: Mixing models are a common method for quantifying the contribution of prey sources to the diet of an individual using stable isotope analysis; however, these models rely upon a known trophic discrimination factor (hereafter, TDF) that results from fractionation between prey and animal tissues. Quantifying TDFs in captive animals is ideal, because diet is controlled and the proportional contributions and isotopic values of all prey items are known. METHODS: To calculate TDFs for the Hawaiian monk seal, northern elephant seal, bearded seal, ringed seal, spotted seal, harbor seal, and California sea lion, we obtained whiskers, serum, plasma, red blood cells, and prey items from nine captive individuals. We obtained δ13C and δ15N values using continuous-flow isotope-ratio mass spectrometry. The average δ13C and δ15N values from bulk and lipid-corrected prey from the diet were subtracted from the δ13C and δ15N values of each blood and whisker sample to calculate tissue-specific TDFs for each individual (Δ13C or Δ15N). RESULTS: The Δ13C values ranged from +1.7 to +3.2‰(bulk prey) and from +0.8 to +1.9‰(lipid-corrected prey) for the various blood components, and from +3.9 to +4.6‰(bulk prey) or +2.6 to +3.9‰(lipid-corrected prey) for whiskers. The Δ15N values ranged from +2.2 to +4.3‰for blood components and from +2.6 to +4.0‰for whiskers. The TDFs tended to group by tissue, with whiskers having greater Δ13C values than blood components. In contrast, the Δ15N values were greater in serum and plasma than in red blood cells and whiskers. CONCLUSIONS: By providing the first TDF values for five seal species (family Phocidae) and one otariid species (family Otariidae), our study facilitates more accurate mixing models for these species. These values are particularly important for critically endangered Hawaiian monk seals and the three Arctic seal species (bearded, ringed, and spotted) that are faced with a rapidly changing environment. [ABSTRACT FROM AUTHOR]