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The organic carbon (Corg) stored in seagrass meadows is globally significant and could be relevant in strategies to mitigate increasing CO2 concentration in the atmosphere. Most of that stored Corg is in the soils that underlie the seagrasses. We explored how seagrass and soil characteristics vary among seagrass meadows across the geographic range of turtlegrass (Thalassia testudinum) with a goal of illuminating the processes controlling soil organic carbon (Corg) storage spanning 23° of latitude. Seagrass abundance (percent cover, biomass, and canopy height) varied by over an order of magnitude across sites, and we found high variability in soil characteristics, with Corg ranging from 0.08 to 12.59% dry weight. Seagrass abundance was a good predictor of the Corg stocks in surficial soils, and the relative importance of seagrass-derived soil Corg increased as abundance increased. These relationships suggest that first-order estimates of surficial soil Corg stocks can be made by measuring seagrass abundance and applying a linear transfer function. The relative availability of the nutrients N and P to support plant growth was also correlated with soil Corg stocks. Stocks were lower at N-limited sites than at P-limited ones, but the importance of seagrass-derived organic matter to soil Corg stocks was not a function of nutrient limitation status. This finding seemed at odds with our observation that labile standard substrates decomposed more slowly at N-limited than at P-limited sites, since even though decomposition rates were 55% lower at N-limited sites, less Corg was accumulating in the soils. The dependence of Corg stocks and decomposition rates on nutrient availability suggests that eutrophication is likely to exert a strong influence on carbon storage in seagrass meadows.

The triarchic model of psychopathy emphasizes the role of three phenotypic personality domains (boldness, meanness, and disinhibition) that have been operationalized using the well-established Multidimensional Personality Questionnaire. The present study sought to further validate the MPQ-Tri scales and examine their temporal stability and predictive validity across two time points (ages 18 and 26) from the Dunedin Multidisciplinary Health and Development Study, a population-representative and longitudinal sample (N = 1,037). This investigation necessitated modification of the MPQ-Tri scales to enable their use in a broader range of samples, including the Dunedin Study. The revised MPQ-Tri scales demonstrated good temporal stability, and correlation and multiple linear regression analyses predominantly revealed associations consistent with theoretical expectations. Overall, the findings provide support for the MPQ-Tri scales as reliable, stable, and valid measures of the triarchic constructs, which provide a unique opportunity to examine highly novel research questions concerning psychopathy in a wide variety of samples.

When investigating metacommunity dynamics, functional differences among species are often assumed to be as important as environmental differences between sites in determining beta-diversity. However, few studies have examined the influence of functional diversity on beta-diversity. We examine the relative importance of regional functional diversity partitioned by niche dimensions and environmental variation in structuring taxonomic beta-diversity of stream fishes using a large dataset of stream fish assemblages (hereafter, simply beta-diversity). We predicted that both functional diversity and environmental variation play a role in determining beta-diversity. We tested this prediction by modelling the patterns of stream fish beta-diversity as a function of environmental variation, functional diversity and gamma-richness across 10,220 sites for 329 fish species using a series of conceptual path models. Environmental variation consistently affected beta-diversity across all models, whereas functional diversity and gamma-richness influenced beta-diversity only in some models. We show that including relevant trait differences among species in path models can improve their ability to explain beta-diversity, suggesting that functional traits influence beta-diversity. The ability of path models to explain beta-diversity varied depending on the trait grouping included in the model, demonstrating that specific path models representing different niche dimensions can improve the ability of a model to explain beta-diversity. In addition, parsing traits into different niche dimensions revealed alternative patterns of functional diversity-beta-diversity relationships that otherwise would have been missed. The selection of relevant traits and linked niche dimensions is critical for detecting relationships between functional diversity and beta-diversity. Using traits associated with different niche dimensions allows for the identification of niche dimensions most strongly associated with species sorting and the detection of patterns missed by focusing on a single niche dimension. Determining the niche dimensions that influence beta-diversity could provide insights into the processes driving biodiversity and metacommunity dynamics, improving our ability to conserve or restore aquatic communities. USDA/NIFA [SC-1700599]; National Science Foundation [DEB-2017795] Published version First and foremost, we thank the numerous agency and university employees who contributed to the dataset. We thank T. Wagner and S. Midway for facilitating access to the fish dataset, and E. Frimpong for access to the FishTraits dataset. This work was supported in part by the USDA/NIFA, under project no. SC-1700599, and represents technical contribution no. 6994 of the Clemson Experiment Station. This material is based upon work supported by the National Science Foundation under project DEB-2017795. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.

Antisocial behavior has been linked to an increased tolerance of painful stimuli; however, there is evidence that pain behavior is multidetermined. The current study used pain measures from 3 different modalities (pain tolerance, pain ratings, electrocortical reactivity) and assessed triarchic traits of boldness and meanness to clarify the dispositional basis of associations between pain processing and antisocial behavior. High boldness was significantly associated with blunted early neural response to painful and nonpainful stimuli as well as increased pain tolerance. High meanness was associated with blunted elaborative processing of painful images, lower ratings of perceived pain for self and others, and increased pain tolerance. Meanness also accounted for variance shared between pain processing and antisocial behavior. Findings demonstrate that boldness and meanness contribute to pain processing in different ways and suggest that meanness may uniquely account for the association between blunted pain processing and antisocial behavior. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

This study explored the generality versus specificity of two trait-liability factors for externalizing problems-disinhibition and callousness-in the concurrent and prospective prediction of symptoms of conduct disorder, attention-deficit/hyperactivity disorder (ADHD), and substance use (i.e., alcohol use disorder and history of illicit substance use). Disinhibition involves an impulsive, unrestrained cognitive-behavioral style; callousness entails a dispositional lack of social-emotional sensitivity. Participants were European adolescents from the multisite IMAGEN project who completed questionnaires and clinical interviews at ages 14 (N = 1,504, Mage = 14.41, 51.13% female) and 16 (N = 1,407, Mage = 16.46, 51.88% female). Disinhibition was related concurrently and prospectively to greater symptoms of conduct disorder, ADHD, and alcohol use disorder; higher scores on a general externalizing factor; and greater likelihood of having tried an illicit substance. Callousness was selectively related to greater conduct disorder symptoms. These findings indicate disinhibition confers broad liability for externalizing spectrum disorders, perhaps due to its affiliated deficits in executive function. In contrast, callousness appears to represent more specific liability for antagonistic (aggressive/exploitative) forms of externalizing, as exemplified by antisocial behavior. Results support the utility of developmental-ontogenetic and hierarchical-dimensional models of psychopathology and have important implications for early assessment of risk for externalizing problems. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Low resting heart rate (HR) is a known risk indicator for the development of antisocial behavior (ASB) and other clinical problems. Stimulation seeking and fearlessness have been explored as factors underlying the HR/ASB relationship, but these have often been conflated, which has complicated interpretation. We examined HR’s associations with ASB and other outcomes in terms of biobehavioral traits described by the triarchic model of psychopathy using data ( N = 710) from a longitudinal study of ASB risk. Low resting HR in childhood was related to adult ASB, and covariance between ASB and traits of disinhibition and boldness largely accounted for this association. In addition, low childhood HR was related to greater externalizing problems and fewer internalizing problems in adulthood; disinhibition accounted for the former association, and boldness accounted for the latter. Findings indicate a role for both disinhibition and boldness in associations between early HR and later clinical outcomes and have implications for theory and practice.

Psychopathy and antisocial personality disorder (ASPD) have been of long-standing interest to clinicians and researchers due to their serious detrimental effects on both individuals and society as a whole. This chapter begins with an overview of historical writings that served as the foundation for modern conceptualizations of psychopathy and ASPD. Next, the chapter describes the main inventories for assessing psychopathy in use today and discusses how these various inventories differ from one another and how they relate to ASPD and other conditions in the official psychiatric nosology (the DSM-5). The chapter also summarizes findings regarding their neurobiological correlates. Following this, the authors describe an integrative conceptual-empirical framework—the triarchic model—for characterizing relations among different psychopathy measures and organizing what is known about their clinical and neurobiological correlates. The chapter then considers how the three constructs of the triarchic model—boldness, meanness, and disinhibition—are represented in the dimensional system for personality pathology within the DSM-5 and how they interface with the Hierarchical Taxonomy of Psychopathology (HiTOP), a new dimensional framework for psychopathology as a whole. Finally, the authors discuss how the triarchic model can be used to guide developmental research on psychopathy and coordinate further research on the role of neurobiological systems and processes in psychopathy.

Although authoritarianism has predominantly been studied among political conservatives, authoritarian individuals exist on both "poles" of the political spectrum. A 39-item multidimensional measure of left-wing authoritarianism, the Left-wing Authoritarianism Index, was recently developed to extend the study of authoritarianism to members of the far-left. The present study coupled a fully automated machine learning approach (i.e., a genetic algorithm) with multidimensional item response theory in a large, demographically representative American sample (N = 834) to generate and evaluate two abbreviated versions of the Left-wing Authoritarianism Index. We subsequently used a second community sample (N = 477) to conduct extensive validational tests of the abbreviated measures, which comprise 25- and 13-items. The abbreviated forms demonstrated remarkable convergence with the full LWA Index in terms of their psychometric (e.g., internal consistency) and distributional (e.g., mean, standard deviation, skew, kurtosis) properties. This convergence extended to virtually identical cross-measure patterns of correlations with 14 external criteria, including need for chaos, political violence, anomia, low institutional trust. In light of these results, the LWA-25 and LWA-13 scales appeared to function effectively as measures of LWA.

The present study sought to extend knowledge of the role of boldness, a transdiagnostic bipolar trait dimension involving low sensitivity to threat, in emotional reactivity and regulation using physiological and report-based measures. One prior study found that boldness was associated with reduced late positive potential (LPP) while passively viewing aversive images, but not during emotion regulation; a disconnect between LPP and self-reported reactivity was also observed. Here, participants (N = 63) completed an emotion regulation task in which they either passively viewed or effortfully up- or downregulated their emotional reactivity to pleasant, unpleasant, and neutral pictures while EEG activity was recorded; they later retrospectively rated the success of their regulation efforts. ANOVAs examining the interactive effects of regulation instruction and boldness on LPP amplitude revealed that lower boldness (higher trait fearfulness) was associated with paradoxical increases in LPP to threat photos during instructed downregulation, relative to passive viewing, along with lower reported regulation success on these trials. Unexpectedly, similar LPP effects were observed for affective images overall, and especially nurturance photos. Although subject to certain limitations, these results suggest that individual differences in boldness play a role not only in general reactivity to aversive stimuli, as evidenced by prior work, but in the ability to effortfully downregulate emotional response.

Research on psychopathy has progressed considerably in recent years against the backdrop of important advances in the broader field of clinical psychological science. My major aim in this review is to encourage integration of investigative work on dispositional, biobehavioral, and developmental aspects of psychopathy with counterpart work on general psychopathology. Using the triarchic model of psychopathy as a frame of reference, I offer perspective on long-standing debates pertaining to the conceptualization and assessment of psychopathy, discuss how dispositional facets of psychopathy relate to subdimensions of internalizing and externalizing psychopathology, and summarize findings from contemporary biobehavioral and developmental research on psychopathy. I conclude by describing a systematic strategy for coordinating biobehavioral-developmental research on psychopathy that can enable it to be informed by, and help inform, ongoing research on mental health problems more broadly.

The validity of self-report psychopathy assessment has been questioned, especially in forensic settings where clinical evaluations influence critical decision-making (e.g., institutional placement, parole eligibility). Informant-based assessment offers a potentially valuable supplement to self-report but is challenging to acquire in under-resourced forensic contexts. The current study evaluated, within an incarcerated sample (n = 322), the extent to which brief prototype-based informant ratings of psychopathic traits as described by the triarchic model (boldness, meanness, disinhibition; Patrick et al., 2009) converge with self-report trait scores and show incremental validity in predicting criterion measures. Self/informant convergence was robust for traits of boldness and disinhibition, but weaker for meanness. Informant-rated traits showed incremental predictive validity over self-report traits, both within and across assessment domains. These findings indicate that simple prototype-based informant ratings of the triarchic traits can provide a useful supplement to self-report in assessing psychopathy within forensic-clinical settings.

The triarchic model of psychopathy conceptualizes variants of this clinical condition as expressions of three distinct biobehavioral dispositions, termed boldness, meanness, and disinhibition. As a trait-oriented model, the triarchic model situates psychopathy within a broader nomological network of personality and psychopathology, and has proven useful for characterizing how psychopathy relates to variables in these domains as well as to biological and behavioral variables. The current study was the first to examine sex differences in the external correlates of psychopathic traits as described by the triarchic model in a prison sample. Results were generally consistent with hypotheses: The triarchic traits related to measures of personality and psychopathology in patterns that were largely consistent across sex, but with some notable differences between males and females, in the correlates of disinhibition in particular. These included stronger associations for disinhibition with substance use problems, self-harm, and staff ratings of prison misbehavior among females compared to males. Findings from this study support the value of the triarchic model for understanding similarities and differences in the nomological network of psychopathy in incarcerated males and females.

Recent initiatives have focused on integrating transdiagnostic biobehavioral processes or dispositions with dimensional models of psychopathology. Toward this goal, biobehavioral traits of affiliative capacity (AFF) and inhibitory control (INH) hold particular promise as they demonstrate transdiagnostic stability and predictive validity across developmental stages and differing measurement modalities. The current study employed data from different modes of measurement in a sample of 1830 children aged 5–10 years to test for associations of AFF and INH, individually and interactively, with broad dimensions of psychopathology. Low AFF, assessed via parent-report, evidenced predictive relations with distress- and externalizing-related problems. INH as assessed by cognitive-task performance did not relate itself to either psychopathology dimension, but it moderated the effects observed for low AFF, such that high INH protected against distress symptoms in low-AFF participants, whereas low INH amplified distress and externalizing symptoms in low-AFF participants. Results are discussed in the context of the interface of general trait transdiagnostic risk factors with quantitatively derived dimensional models of psychopathology.

Understanding factors that influence behavioral performance in high-pressure contexts is relevant to critical occupations such as first responders, military personnel, and frontline medical workers. A recent study by Yancey et al. (2019) demonstrated an association between boldness, a biobehavioral trait reflecting social dominance and fearlessness, and enhanced task-switching performance during threat of shock relative to a no-shock (safe) condition. This study used a sustained threat manipulation in which cues signaling possible shock were present throughout blocks of multiple task trials. Here, we extended this work by evaluating the relationship between boldness and task-switching performance under acute threat of shock conditions, in which cues signaling possible shock occurred during individual task trials, intermingled with safe trials. Participants (

The triarchic model was advanced as an integrative, trait-based framework for investigating psychopathy using different assessment methods and across developmental periods. Recent research has shown that the triarchic traits of boldness, meanness, and disinhibition can be operationalized effectively in youth, but longitudinal research is needed to realize the model's potential to advance developmental understanding of psychopathy. We report on the creation and validation of scale measures of the triarchic traits using questionnaire items available in the University of Southern California Risk Factors for Antisocial Behavior (RFAB) project, a large-scale longitudinal study of the development of antisocial behavior that includes measures from multiple modalities (self-report, informant rating, clinical-diagnostic, task-behavioral, physiological). Using a construct-rating and psychometric refinement approach, we developed triarchic scales that showed acceptable reliability, expected intercorrelations, and good temporal stability. The scales showed theory-consistent relations with external criteria including measures of psychopathy, internalizing/externalizing psychopathology, antisocial behavior, and substance use. Findings demonstrate the viability of measuring triarchic traits in the RFAB sample, extend the known nomological network of these traits into the developmental realm, and provide a foundation for follow-up studies examining the etiology of psychopathic traits and their relations with multimodal measures of cognitive-affective function and proneness to clinical problems.

Shortcomings of approaches to classifying psychopathology based on expert consensus have given rise to contemporary efforts to classify psychopathology quantitatively. In this paper, we review progress in achieving a quantitative and empirical classification of psychopathology. A substantial empirical literature indicates that psychopathology is generally more dimensional than categorical. When the discreteness versus continuity of psychopathology is treated as a research question, as opposed to being decided as a matter of tradition, the evidence clearly supports the hypothesis of continuity. In addition, a related body of literature shows how psychopathology dimensions can be arranged in a hierarchy, ranging from very broad "spectrum level'' dimensions, to specific and narrow clusters of symptoms. In this way, a quantitative approach solves the "problem of comorbidity'' by explicitly modeling patterns of co-occurrence among signs and symptoms within a detailed and variegated hierarchy of dimensional concepts with direct clinical utility. Indeed, extensive evidence pertaining to the dimensional and hierarchical structure of psychopathology has led to the formation of the Hierarchical Taxonomy of Psychopathology (HiTOP) Consortium. This is a group of 70 investigators working together to study empirical classification of psychopathology. In this paper, we describe the aims and current foci of the HiTOP Consortium. These aims pertain to continued research on the empirical organization of psychopathology; the connection between personality and psychopathology; the utility of empirically based psychopathology constructs in both research and the clinic; and the development of novel and comprehensive models and corresponding assessment instruments for psychopathology constructs derived from an empirical approach. (C) 2020 Published by Elsevier Masson SAS.

Author(s): Hopwood, Christopher J; Krueger, Robert F; Watson, David; Widiger, Thomas A; Althoff, Robert R; Ansell, Emily B; Bach, Bo; Bagby, R Michael; Blais, Mark A; Bornovalova, Marina A; Chmielewski, Michael; Cicero, David C; Conway, Christopher; De Clerq, Barbara; De Fruyt, Filip; Docherty, Anna R; Eaton, Nicholas R; Edens, John F; Forbes, Miriam K; Forbush, Kelsie T; Hengartner, Michael P; Ivanova, Masha Y; Leising, Daniel; Lukowitsky, Mark R; Lynam, Donald R; Markon, Kristian E; Miller, Joshua D; Morey, Leslie C; Mullins-Sweatt, Stephanie N; Ormel, Johan; Patrick, Christopher J; Pincus, Aaron L; Ruggero, Camilo; Samuel, Douglas B; Sellbom, Martin; Tackett, Jennifer L; Thomas, Katherine M; Trull, Timothy J; Vachon, David D; Waldman, Irwin D; Waszczuk, Monika A; Waugh, Mark H; Wright, Aidan GC; Yalch, Mathew M; Zald, David H; Zimmermann, Johannes

The DSM-5 alternative model for personality disorders (AMPD) groups traits into domains based on factor analyses of self-report data. AMPD traits may need to be configured differently to interface with neurobiology. Focusing on biobehavioral risk for externalizing problems in 334 adults, the authors used structural modeling to evaluate how well alternative configurations of AMPD traits, operationalized using the Personality Inventory for DSM-5 (PID-5), interface with neural indicators of externalizing liability. A model specifying two correlated factors defined by traits within the PID-5 Disinhibition domain and brain-response indicators of externalizing proneness exhibited inadequate fit. However, a model using PID-5 traits with better coverage of biobehavioral externalizing liability evidenced good fit. Scores on this PID-5 trait factor, termed “PID-5 Externalizing Proneness,” converged well with criterion measures of externalizing proneness and diverged from measures of threat sensitivity. Findings illustrate how AMPD traits can be configured for use in investigations of biobehavioral risk for psychopathology.

Tropical cyclones drive coastal ecosystem dynamics, and their frequency, intensity, and spatial distribution are predicted to shift with climate change. Patterns of resistance and resilience were synthesized for 4138 ecosystem time series from n = 26 storms occurring between 1985 and 2018 in the Northern Hemisphere to predict how coastal ecosystems will respond to future disturbance regimes. Data were grouped by ecosystems (fresh water, salt water, terrestrial, and wetland) and response categories (biogeochemistry, hydrography, mobile biota, sedentary fauna, and vascular plants). We observed a repeated pattern of trade-offs between resistance and resilience across analyses. These patterns are likely the outcomes of evolutionary adaptation, they conform to disturbance theories, and they indicate that consistent rules may govern ecosystem susceptibility to tropical cyclones.

Microbes play a critical role in plant litter decomposition and influence the fate of carbon in rivers and riparian zones. When decomposing low-nutrient plant litter, microbes acquire nitrogen (N) and phosphorus (P) from the environment (i.e., nutrient immobilization), and this process is potentially sensitive to nutrient loading and changing climate. Nonetheless, environmental controls on immobilization are poorly understood because rates are also influenced by plant litter chemistry, which is coupled to the same environmental factors. Here we used a standardized, low-nutrient organic matter substrate (cotton strips) to quantify nutrient immobilization at 100 paired stream and riparian sites representing 11 biomes worldwide. Immobilization rates varied by three orders of magnitude, were greater in rivers than riparian zones, and were strongly correlated to decomposition rates. In rivers, P immobilization rates were controlled by surface water phosphate concentrations, but N immobilization rates were not related to inorganic N. The N:P of immobilized nutrients was tightly constrained to a molar ratio of 10:1 despite wide variation in surface water N:P. Immobilization rates were temperature-dependent in riparian zones but not related to temperature in rivers. However, in rivers nutrient supply ultimately controlled whether microbes could achieve the maximum expected decomposition rate at a given temperature. Collectively, we demonstrated that exogenous nutrient supply and immobilization are critical control points for decomposition of organic matter. Key Points • Nitrogen (N) and phosphorus (P) immobilization was measured on organic matter (cotton) in 100 rivers and riparian zones representing 11 biomes • Elevated temperature in riparian zones and phosphate in rivers increased immobilization, and consequently accelerated decomposition • N and P immobilization was strongly linked by microbial stoichiometry despite widely varied surface-water nutrient ratios Plain Language Summary Bacteria and fungi contribute to the breakdown of leaf litter in rivers and floodplains. To break down leaf litter, these microbes need the nutrients nitrogen and phosphorus (P), and microbes can get nutrients either from the leaf litter itself or from the environment. Most leaf litter has low nutrient content and microbes must rely on the environment to supply nutrients. We studied microbial nutrient uptake from the environment during litter breakdown to determine whether it varies predictably across the globe and how it is influenced by changing climate and nutrient pollution. In 100 rivers and floodplains in 11 of Earth's major biomes we placed small strips of cotton as stand-ins for leaf litter. Nutrient uptake was consistently greater on cotton strips that were submerged in the river compared to cotton on the floodplain. For microbes in the river, nutrient uptake was faster in instances where there was more P in the water. For microbes in the floodplain, nutrient uptake was faster where temperatures were warmer. Faster nutrient uptake by microbes was linked with faster cotton breakdown in rivers and floodplains. Our study shows that climate change and nutrient pollution can alter the activity of microbes in rivers and floodplains.

The triarchic model of psychopathy posits that three distinct trait dispositions-disinhibition, meanness, and boldness-contribute to the interpersonal, affective, and impulsive-unrestrained features of this condition and is represented to varying degrees in all conceptualizations and measures of psychopathy. Using data for incarcerated males (

Human impacts, particularly nutrient pollution and land-use change, have caused significant declines in the quality and quantity of freshwater resources. Most global assessments have concentrated on species diversity and composition, but effects on the multifunctionality of streams and rivers remain unclear. Here, we analyse the most comprehensive compilation of stream ecosystem functions to date to provide an overview of the responses of nutrient uptake, leaf litter decomposition, ecosystem productivity, and food web complexity to six globally pervasive human stressors. We show that human stressors inhibited ecosystem functioning for most stressor-function pairs. Nitrate uptake efficiency was most affected and was inhibited by 347% due to agriculture. However, concomitant negative and positive effects were common even within a given stressor-function pair. Some part of this variability in effect direction could be explained by the structural heterogeneity of the landscape and latitudinal position of the streams. Ranking human stressors by their absolute effects on ecosystem multifunctionality revealed significant effects for all studied stressors, with wastewater effluents (194%), agriculture (148%), and urban land use (137%) having the strongest effects. Our results demonstrate that we are at risk of losing the functional backbone of streams and rivers if human stressors persist in contemporary intensity, and that freshwaters are losing critical ecosystem services that humans rely on. We advocate for more studies on the effects of multiple stressors on ecosystem multifunctionality to improve the functional understanding of human impacts. Finally, freshwater management must shift its focus toward an ecological function-based approach and needs to develop strategies for maintaining or restoring ecosystem functioning of streams and rivers. Generalitat de Catalunya, Grant/Award Number: 2017SGR0976; Portuguese Foundation for Science and Technology, Grant/Award Number: CEEIND/02484/2018 and UIDP/04292/2020