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Adolescents' suicidal behavior frequently is preceded by interpersonal stress, but not all who experience distress attempt to end their lives. Recent theories have posited individual differences in stress-related inflammatory reactivity may be associated with psychopathology risk; this study examined inflammatory reactivity as a moderator of the prospective association between interpersonal stress and adolescents' suicidal behavior. Participants included 157 at-risk adolescent females (ages 12 to 16 years) and assessed individual differences in proinflammatory cytokine responses to a brief laboratory-based social stressor, both interpersonal and non-interpersonal life events, and suicidal behavior over an 18-month follow-up period. Measuring levels of the key proinflammatory cytokines interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) before and after an experimentally-induced social stressor, results revealed that blunted cytokine reactivity heightened the effect of high interpersonal stress exposure on risk for suicidal behaviors over the subsequent 9 months. Significant effects were not revealed for non-interpersonally themed stress. Finding highlight the urgent need for more research examining inflammation reactivity among adolescents.

Fish in all the world's oceans exhibit variable body size and growth over time, with some populations exhibiting long- term declines in size. These patterns can be caused by a range of biotic, abiotic, and anthropogenic factors and impact the productivity of harvested populations. Within a given species, individuals often exhibit a range of life history strategies that may cause some groups to be buffered against change. One of the most studied declines in size-at-age has been in populations of salmon; Chinook salmon in the Northeast Pacific Ocean are the largest-bodied salmon species and have experienced long-term declines in size. Using long-term monitoring data, we develop novel size and growth models to link observed changes in Chinook size to life history traits and environmental variability. Our results identify three distinct trends in size across the 48 stocks in our study. Differences among populations are correlated with ocean distribution, migration timing, and freshwater residence. We provide evidence that trends are driven by interannual variation in certain oceanographic processes and competition with pink salmon. Key words: life histories, environmental change, pink salmon, competition, state-space models, Oncorhynchus tshawytscha, Introduction Many fish species around the world targeted by commercial or recreational fisheries have exhibited declines in mean size; examples include Atlantic salmon (Quinn et al. 2006; Kuparinen et al. [...]

Suicidal ideation (SI) is a significant public health concern with increasing prevalence. Therapist-supported digital mental health interventions (DMHI) are an emergent modality to address common mental health problems like depression and anxiety, although less is known about SI. This study examined SI trajectories among 778 patients who participated in a therapist-supported DMHI using multilevel models during and up to 6-months post-treatment. Estimates of associated suicide attempts and deaths by suicide were calculated using published data linking PHQ-9-assessed SI to records of suicide attempts and deaths by suicide. The proportion of participants reporting no SI significantly increased between baseline and end-of-treatment (78.02% to 91.00%). Effect sizes of SI changes between baseline and end-of-treatment, 3-month, and 6-month follow-ups were 0.33 (95%CI = 0.27–0.38), 0.32 (95%CI = 0.27–0.38), and 0.32 (95%CI = 0.27–0.38), respectively. Results also indicated an estimated 30.49% reduction (95%CI = 25.15%-35.13%) in suicide attempts and death by suicide across treatment. This study provides preliminary evidence of the effectiveness of a therapist-supported DMHI in reducing SI. [ABSTRACT FROM AUTHOR]

Purpose: This study examined treatment outcomes (depression and anxiety symptoms) up to 24 months after completion of a therapist‐supported digital mental health intervention (DMHI). Methods: The sample consisted of 380 participants who participated in an eight‐week DMHI from February 6, 2017 to May 20, 2019. Participants reported depression and anxiety symptoms at eight timepoints from baseline to 24 months. Mixed‐effects modelling was used to investigate symptom changes over time. The proportion of participants meeting criteria for treatment response, clinically significant change, and remission of depression and anxiety symptoms were calculated, including proportions demonstrating each outcome sustained up to each timepoint. Results: Multivariate analyses yielded statistically significant reductions in depression (β = −5.40) and anxiety (β = −3.31) symptoms from baseline to end of treatment (8 weeks). Symptom levels remained significantly reduced from baseline through 24 months. The proportion of participants meeting criteria for clinical treatment outcomes remained constant over 24 months, although there were linear decreases in the proportions experiencing sustained clinical outcomes. Conclusions: Treatment gains were made for depression and anxiety symptoms at the end of treatment and up to 24 months. Future studies should determine the feasibility of integrating post‐treatment programmes into DMHIs to address symptom deterioration. [ABSTRACT FROM AUTHOR]

Management of protected species is difficult when objectives include the recovery of both predator and its prey. Ideally, identifying trade-offs between competing objectives involves evaluating management alternatives with a quantitative model that integrates information on both species, but data are often limited. We used new predator diet data and simulation modeling to update our understanding of seal predation on juvenile Chinook (Oncorhynchus tshawytscha) and coho salmon (Oncorhynchus kisutch) in the Puget Sound. Under prey size assumptions used by previous studies, estimates suggest predation could be a significant source of mortality for Chinook salmon (mean: 37% of ocean age-0 juveniles), but varied considerably among years (range of median estimates: 22%-49%). However, when we estimated prey size from otoliths recovered from seal scats, the impact (numbers of fish consumed) decreased by 71%. Predation on coho salmon was estimated to be relatively low under both scenarios (6%-8% of ocean age-0 juveniles) with a 21% decrease in consumption using otolith-derived prey size. Our analysis highlights the importance of updating model inputs and re-evaluating assumptions of multi-species models used for ecosystem-based fisheries management. La gestion d'especes protegees est difficile quand les objectifs comprennent le retablissement tant d'un predateur que de sa proie. Si, idealement, la determination des compromis entre objectifs concurrents comprend l'evaluation de differentes options de gestion a l'aide d'un modele quantitatif qui integre de l'information sur les deux especes, les donnees sont souvent limitees. Nous utilisons de nouvelles donnees sur le regime alimentaire de predateurs et la modelisation de simulation afin d'actualiser la comprehension de la predation par les phoques de saumons chinooks (Oncorhynchus tshawytscha) et cohos (Oncorhynchus kisutch) juveniles dans le Puget Sound. Des estimations etablies a partir d'hypotheses sur la taille des proies utilisees dans des etudes anterieures indiqueraient que la predation pourrait constituer une source de mortalite significative de saumons chinooks (moyenne : 37 % des juveniles de moins de 1 an en ocean), mais varie considerablement d'une annee a l'autre (fourchette de valeurs medianes estimees : 22 %-49 %). Cependant, quand nous estimons la taille des proies a partir d'otolites recuperes d'excrements de phoque, l'impact (le nombre de poissons consommes) diminue de 71 %. Il est estime que la predation de saumons cohos est relativement faible dans les deux scenarios (6 %-8 % des juveniles de moins de 1 an en ocean), et la taille des proies etablie sur la base des otolites indique une diminution de 21 % de la consommation. Notre analyse souligne l'importance d'actualiser les intrants des modeles et de reevaluer les hypotheses des modeles multispecifiques utilises pour la gestion ecosystemique des peches. [Traduit par la Redaction], Introduction Management conflicts between protected marine species are increasing, and successful resolution requires identification of competing objectives and evaluating the ecological, social, and economic trade-offs associated with various management scenarios [...]

Effective conservation of threatened populations requires identification of the processes limiting recovery. When multiple population processes are potentially limiting, they are sometimes analyzed independently, often using different datasets. Analytically, this is suboptimal, as processes are often correlated, which can lead to biased estimates of parameters and quantities of interest. Integrated population models (IPMs) can synthesize several data streams in the same probabilistic framework to circumvent these issues. Lack of prey was identified as one of the primary threats to recovery of critically endangered southern resident killer whales (SRKWs), Orcinus orca. Previous studies have correlated SRKW demographic rates with indices of Chinook salmon Oncorhynchus tshawytscha abundance, but these approaches have modeled reproduction and survival independently. We developed an IPM for SRKWs that models both processes simultaneously, as a function of Chinook salmon abundance along the west coast of North America. We used this model to evaluate the relationship between Chinook salmon abundance and demographic rates of SRKWs, with the goal of updating our understanding of a potential causal relationship between prey availability and SRKW population dynamics, and how these relationships may have changed over time. Results suggest that SRKW mortality rates are more strongly associated with Chinook salmon abundance than birth rates. Our analysis also suggests northern resident killer whale abundance could also be affecting SRKW carrying capacity, possibly through competition over shared prey resources. The IPM fit observed total abundance data well and predicted temporal changes in population demographics with reasonable accuracy, but small sample size may have opacified model selection. Our approach offers a valuable tool for predicting the response of the SRKW population to alternative management strategies involving the recovery of Chinook salmon stocks in the eastern Pacific. [ABSTRACT FROM AUTHOR]

Predation risk and competition among conspecifics significantly affect survival of juvenile salmon, but are rarely incorporated into models that predict recruitment in salmon populations. Using densities of harbour seals (Phoca vitulina) and numbers of hatchery-released Chinook salmon (Oncorhynchus tshawytscha) smolts as covariates in spatially structured Bayesian hierarchical stock-recruitment models, we found significant negative correlations between seal densities and productivity of Chinook salmon for 14 of 20 wild Chinook populations in the Pacific Northwest. Changes in numbers of seals since the 1970s were associated with a 74% decrease (95% CI: -85%, -64%) in maximum sustainable yield in Chinook stocks. In contrast, hatchery releases were significantly correlated with Chinook productivity in only one of 20 populations. Our findings are consistent with recent research on predator diets and bioenergetics modeling that suggest there is a relationship between harbour seal predation on juvenile Chinook and reduced marine survival in parts of the eastern Pacific. Forecasting, assessment, and recovery efforts for salmon populations of high conservation concern should thus consider including biotic factors, particularly predatorprey interactions. Le risque de predation et la concurrence entre individus d'une meme espece ont une incidence significative sur la survie des saumons juveniles, mais sont rarement integres dans les modeles qui predisent le recrutement dans les populations de saumons. En utilisant la densite de phoques communs (Phoca vitulina) et le nombre de saumoneaux relaches d'ecloseries comme covariables dans des modeles bayesiens hierarchiques spatialement structures de recrutement au stock, nous avons constate la presence de correlations negatives significatives entre la densite de phoques et la productivite de saumons quinnats (Oncorhynchus tshawytscha) pour 14 des 20 populations de saumons quinnats sauvages dans le Pacific Northwest. Des variations des nombres de phoques depuis les annees 1970 sont associees a une baisse de 74 % (IC a 95 % : -85 %, -64 %) du rendement equilibre maximal dans les stocks de saumons quinnats. En revanche, le nombre de saumoneaux relaches d'ecloseries n'est significativement correle a la productivite des saumons quinnats que dans 1 des 20 populations. Nos constatations concordent avec celles de travaux recents sur les regimes alimentaires de predateurs et la modelisation bioenergetique qui donnent a penser qu'il existe une relation entre la predation de saumons quinnats juveniles par les phoques communs et une survie en mer reduite dans certaines parties de l'est de l'ocean Pacifique. La prediction, l'evaluation et les efforts de retablissement de populations de saumons dont la conservation est tres preoccupante devraient donc integrer des facteurs biotiques, en particulier les interactions predateurs-proies. [Traduit par la Redaction], Introduction The abundance of predators and intensity of competition within a spatial arena give rise to risks associated with foraging activities that may ultimately affect the survival rates of juvenile [...]

BackgroundWrist-worn smart watches and fitness monitors (ie, wearables) have become widely adopted by consumers and are gaining increased attention from researchers for their potential contribution to naturalistic digital measurement of health in a scalable, mobile, and unobtrusive way. Various studies have examined the accuracy of these devices in controlled laboratory settings (eg, treadmill and stationary bike); however, no studies have investigated the heart rate accuracy of wearables during a continuous and ecologically valid 24-hour period of actual consumer device use conditions. ObjectiveThe aim of this study was to determine the heart rate accuracy of 2 popular wearable devices, the Apple Watch 3 and Fitbit Charge 2, as compared with the gold standard reference method, an ambulatory electrocardiogram (ECG), during consumer device use conditions in an individual. Data were collected across 5 daily conditions, including sitting, walking, running, activities of daily living (ADL; eg, chores, brushing teeth), and sleeping. MethodsOne participant, (first author; 29-year-old Caucasian male) completed a 24-hour ecologically valid protocol by wearing 2 popular wrist wearable devices (Apple Watch 3 and Fitbit Charge 2). In addition, an ambulatory ECG (Vrije Universiteit Ambulatory Monitoring System) was used as the gold standard reference method, which resulted in the collection of 102,740 individual heartbeats. A single-subject design was used to keep all variables constant except for wearable devices while providing a rapid response design to provide initial assessment of wearable accuracy for allowing the research cycle to keep pace with technological advancements. Accuracy of these devices compared with the gold standard ECG was assessed using mean error, mean absolute error, and mean absolute percent error. These data were supplemented with Bland-Altman analyses and concordance class correlation to assess agreement between devices. ResultsThe Apple Watch 3 and Fitbit Charge 2 were generally highly accurate across the 24-hour condition. Specifically, the Apple Watch 3 had a mean difference of −1.80 beats per minute (bpm), a mean absolute error percent of 5.86%, and a mean agreement of 95% when compared with the ECG across 24 hours. The Fitbit Charge 2 had a mean difference of −3.47 bpm, a mean absolute error of 5.96%, and a mean agreement of 91% when compared with the ECG across 24 hours. These findings varied by condition. ConclusionsThe Apple Watch 3 and the Fitbit Charge 2 provided acceptable heart rate accuracy (

Pinniped populations around the world increased rapidly after hunting and culling during the nineteenth and twentieth centuries ended. Some believe that pinnipeds are now preventing the recovery of certain fish populations, and that controlling pinniped population abundance using lethal measures such as harvesting or by non‐lethal means like contraception could recover fish populations. It is unclear, however, how effective and how long it would take for such methods of population control to bring numbers of pinnipeds down to target levels. We used sex‐ and age‐structured population models to estimate how quickly harbor seal (Phoca vitulina) abundance in British Columbia, Canada, could be reduced by 50%, through combinations of lethal removals and sterilization of adult females. Models were fit to seal abundance, demographic, and harvest data collected between 1879 and 2014. Simulation modeling suggests reliance on contraception exclusively is unlikely to reduce the current harbor seal population (numbering ~100,000) by 50% within 25 years, and would result in more variable outcomes, compared to lethal removals. Contraception could be combined with harvesting to maintain a target abundance of harbor seals (although captive studies with harbor seals are needed to confirm the efficacy of contraception). Our simulation modeling approach provides a useful framework to assess how non‐lethal measures could be integrated into policies that promote active population control of harbor seal numbers. [ABSTRACT FROM AUTHOR]

Knowing the species and life stages of prey that predators consume is important for understanding the impacts that predation may have on prey populations, but traditional methods for determining diets often cannot provide sufficient detail. We combined data from two methods of scat analysis (DNA metabarcoding and morphological prey ID) to quantify the species and life stages of salmon (Oncorhynchus spp.) consumed by harbour seals (Phoca vitulina) in the Strait of Georgia, Canada, where juvenile Chinook (Oncorhynchus tshawytscha) and coho (Oncorhynchus kisutch) salmon survival is poor. Harbour seals primarily consumed adult salmon of lesser conservation concern in the fall (August-November): chum (Oncorhynchus keta: 18.4%), pink (Oncorhynchus gorbuscha: 12.6%), sockeye (Oncorhynchus nerka: 7.4%), Chinook (7.1%), and coho (1.8%). However, the opposite species trend occurred during the spring when seals preferred juvenile salmon of greater conservation concern (April-July): coho (2.9%), Chinook (2.9%), sockeye (2.5%), pink (1.4%), and chum (0.8%)--percentages that can equate to many individuals consumed. Our data suggest that harbour seals select juveniles of salmon species that out-migrate at ages >1 year and provide evidence of a potential causal relationship between harbour seal predation and juvenile salmon survival trends. Il importe de connaitre l'espece et l'etape du cycle biologique des proies que les predateurs consomment afin de comprendre les impacts que la predation peut avoir sur les populations de proies. Dans bien des cas, les methodes traditionnelles de determination du regime alimentaire ne peuvent toutefois fournir assez de details. Nous avons combine des donnees de deux methodes d'analyse d'excrements (meta-codes-barres d'ADN et identification morphologique des proies) pour quantifier l'espece et l'etape du cycle biologique de saumons (Oncorhynchus spp.) consommes par des phoques communs (Phoca vitulina) dans le detroit de Georgia (Canada), ou la survie des saumons quinnats (Oncorhynchus tshawytscha) et cohos (Oncorhynchus kisutch) juveniles est faible. Les donnees indiquent que, a l'automne (d'aout a novembre), les phoques communs consomment principalement des saumons adultes dont la conservation est moins preoccupante, a savoir des saumons ketas (Oncorhynchus keta : 18,4 %), roses (Oncorhynchus gorbuscha : 12,6%), rouges (Oncorhynchus nerka : 7,4%), quinnats (7,1%) et cohos (1,8%). Cependant, cette tendance est inversee au printemps (d'avril a juillet), alors que les phoques privilegient des saumons juveniles dont la conservation est plus preoccupante, a savoir des saumons cohos (2,9%), quinnats (2,9%), rouges (2,5%), roses (1,4%) et ketas (0,8%), ces pourcentages pouvant equivaloir a de nombreux individus consommes. Nos donnees laissent croire que les phoques communs choisissent des juveniles d'especes de saumon qui migrent vers la mer a des ages de plus d'un an et indiqueraient une possible relation de causalite entre la predation par les phoques communs et les tendances de survie des saumons juveniles. [Traduit par la Redaction], Introduction Predators can have different net effects on ecological communities depending on the life stage of prey they consume (Hastings 1983; 1988; Werner and Gilliam 1984). This is because prey [...]

This study examined how adolescents' risk‐taking behaviors were related to their prosocial behaviors on a daily level and how this association differed depending on adolescents' daily and average levels of sensation seeking and social craving. Adolescents (N = 212; Mage = 15 years) completed daily diaries for 14 days. Adolescents were more likely to engage in prosocial behavior on days when they also took risks, but only when they also felt high levels of social craving. The daily link between risk‐taking and prosocial behavior did not vary based on daily or individual differences in sensation seeking. Results suggest that when adolescents feel highly motivated to connect with others, their risk‐taking and prosocial tendencies co‐occur on a daily basis. [ABSTRACT FROM AUTHOR]