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Introduction: Persons with social anxiety disorder (SAD) often experience social interactions as threatening and commonly avoid them or perform poorly in them (Asher et al., 2017). Self-affirmation is an intervention shown to help individuals engage effectively in situations they perceive as threatening (Sherman & Hartson, 2011). We hypothesized that self-affirmation would allow socially anxious individuals to participate in more social activities, do so more effectively, and with less stress and anxiety. Methods: Following completion of baseline measures, 75 socially anxious university students were randomly assigned to complete a self-affirming or control writing task. They subsequently completed the Trier Social Stress Test for Groups (TSST-G), and received SAD psychoeducation designed to promote social engagement over the coming month, after which they were reassessed on baseline measures of social anxiety. Results Self-affirmation demonstrated no benefit at the time of engagement in the TSST-G. However, at follow-up, self-affirmed students reported significantly less discomfort, anxiety, and distress related to a variety of social behaviors as well as more engagement in those behaviors, relative to baseline, compared with non-affirmed students. Moreover, significantly more affirmed than non-affirmed participants reported clinically significant reductions in symptoms of SAD at follow-up. Discussion These results help to broaden our conceptualization of self-affirmation and provide support for its potential utility in treatment for those with SAD.

Introduction Depression and problem drinking are comorbid in emerging adulthood, yet the processes that link them are not well understood. Research has argued that shame has a unique influence on the experience of problematic drinking, but this has rarely been assessed at the state level. Using ecological momentary assessments (EMAs), we assessed whether shame, and not guilt, mediated the association between baseline depression and alcohol use and problems. Methods One hundred and eighty-four emerging adults (Mage= 19.27) completed a 12-day EMA study. Multilevel models were used to test hypotheses. Results In a model with alcohol use as the outcome, there were no significant associations between shame or guilt and alcohol use at the within- or between-subjects level. In a model with alcohol problems as the outcome, guilt was positively associated with alcohol problems but only at the daily level. At the between-subjects level and after controlling for guilt, there was a significant association between depression, shame, and alcohol problems; average levels of shame mediated the association between depression and alcohol problems. In post-hoc reverse directionality models, average alcohol problems mediated the relationship between depression and shame and guilt at the between-person level. No mediation was present for alcohol use. Conclusion After controlling for guilt, shame is an emotion that helps explain risk for alcohol problems among depressed emerging adults, which has implications for targeted interventions. Reciprocal associations between shame, guilt, and alcohol problems emerged highlighting the need for more fulsome assessments of shame and guilt in future EMA research.

Anthropogenic pressures alter the biodiversity, structure and organization of biological communities with severe consequences for ecosystem processes. Species invasion is such a human-induced ecosystem change with pronounced impacts on recipient ecosystems. Around the globe, earthworms invade habitats and impact abiotic soil conditions and a wide range of above- and belowground organisms. In northern North America, where earthworms have been largely absent since the last glaciation period and most earthworm species present today have only been (re-)introduced a few hundred years ago, invasion impacts have been intensively studied. However, despite several studies assessing impacts of invasive earthworms on soil fauna, studies have rarely investigated the simultaneous responses of different soil-fauna size groups and biodiversity facets which might respond differently to earthworm invasion and independently affect ecosystem processes. Our study goes beyond previously-established knowledge on earthworm-invasion effects by simultaneously assessing differences in four biodiversity facets, namely the abundance, biomass, richness and Shannon index of soil invertebrate macro-, meso- and microfauna communities between high- and low-invasion status plots (n = 80) and in relation to invasion intensity measured as earthworm biomass across four northern North American forests sampled between 2016 and 2017. Across forests and soil-fauna groups, we found reduced abundance (−33 to −45%) and richness (−18 to −25%) in high compared to low-invasion status areas. Additionally, meso- (−14%) and microfauna biomass (−38%) and macro- (−7%) and microfauna Shannon index (−8%) were reduced. Higher invasion intensity (earthworm biomass) was additionally related to reduced soil-fauna biodiversity. While the studied biodiversity facet was important for the soil fauna response, soil-fauna size group was comparably unimportant. Given the global ubiquity of earthworm invasion and the importance of soil fauna for key ecosystem processes, our observational results help to assess future impacts of this invasion and the consequences for anthropogenically-altered ecosystem functioning.

Aims Comorbid alcohol use and depression have the highest prevalence among emerging adults and are associated with a number of consequences. Self-medication theory posits individuals with depression use alcohol to cope with their negative emotions. Preliminary work has investigated the social context of depression-related drinking and found that solitary drinking is a risky, atypical behaviour in emerging adulthood that is associated with alcohol misuse. However, it is unknown about what is unfolding in the moment that is driving depression-related drinking in solitary contexts. Accordingly, we used an experimental study to examine if shame mediated the association between depression and in-lab alcohol craving. Methods Emerging adults (N = 80) completed a shame induction followed by an alcohol cue exposure in either a solitary or social condition. We used moderated mediation to test hypotheses. Results Consistent with hypotheses, conditional indirect effects supported the mediation of depression and alcohol craving through shame among those in the solitary condition, but not in the social condition. There was no support for guilt as a mediator. Conclusion Our study demonstrates that shame is a specific emotional experience that contributes to solitary drinking among depressed emerging adults. It is important to use these results to inform interventions that directly target solitary contexts and shame.

The propensity of lithium to form nonplanar, mossy, or dendritic electrodeposits at current densities below the diffusion limit is a well-known, fundamental barrier to commercialization of energy-dense storage in lithium metal batteries. It has been proposed that proliferation of Li dendrites can be eliminated by controlling the uniformity and size of the deposits to levels where surface tension and other small-scale interfacial forces are able to planarize the deposition. Herein, we investigate lithium electrodeposition in uniformly porous, nanostructured media formed in cross-linked poly(ethylene oxide) polymer networks enabled by thiol-ene click chemistry. Using galvanostatic strip-plate experiments along with scanning electron microscopy and operando visualization techniques, we critically assess the effectiveness of these materials in enabling uniform, planar deposition of lithium. We report that thiol-ene click networks that host a liquid electrolyte in their pores are more effective than their liquid electrolyte or solid polymer network components in regulating Li deposition at both the nucleation and growth phases. It is shown further that compressive interfacial stresses imparted by the networks during electrodeposition may serve to augment surface tension to enable uniform Li electrodeposition. The practical relevance of these electrolytes is demonstrated in full-cell battery configurations with excellent long-term stability.

Reactive metals are known to electrodeposit with irregular morphological features on planar substrates. A growing body of work suggest that multiple variables: composition, mechanics, structure, ion transport properties, reductive stability, and interfacial energy of interphases, formed either spontaneously or by design on the metal electrode play important but differentiated roles in regulating these morphologies. We examine the effect of fluorinated thermoset polymer coatings on Li deposition by means of experiment and theoretical linear stability analysis. By tuning the chemistry of the polymer backbone and side chains, we investigate how physical and mechanical properties of polymeric interphases influence Li electrodeposit morphology. It is found that an interplay between elasticity and diffusivity leads to an optimum interphase thickness and that higher interfacial energy augments elastic stresses at a metal electrode to prevent out-of-plane deposition. These findings are explained using linear stability analysis of electrodeposition and provide guidelines for designing polymer interphases to stabilize metal anodes in rechargeable batteries.

The leaf economic traits such as leaf area, maximum carbon assimilation rate, and venation are all correlated and related to water availability. Furthermore, leaves are often broad and large in humid areas and narrower in arid/semiarid and hot and cold areas. We use optimization theory to explain these patterns. We have created a constrained optimization leaf model linking leaf shape to vein structure that is integrated into coupled transpiration and carbon assimilation processes. The model maximizes net leaf carbon gain (NPPleaf) over the loss of xylem water potential. Modeled relations between leaf traits are consistent with empirically observed patterns. As the results of the leaf shape–venation relation, our model further predicts that a broadleaf has overall higher NPPleaf compared to a narrowleaf. In addition, a broadleaf has a lower stomatal resistance compared to a narrowleaf under the same level of constraint. With the same leaf area, a broadleaf will have, on average, larger conduits and lower total leaf xylem resistance and thus be more efficient in water transportation but less resistant to cavitation. By linking venation structure to leaf shape and using water potential as the constraint, our model provides a physical explanation for the general pattern of the covariance of leaf traits through the safety–efficiency trade‐off of leaf hydraulic design., A leaf model integrates venation and leaf shape in coupled photosynthesis and transpiration processes to maximize carbon assimilation rate. Model predicts a general increase in trend‐leaf size and net leaf carbon gain with water status by coadjustment of stomatal and xylem resistance. With same water status, narrower leaf has lower net carbon gain but larger number of smaller conduits indicating safety‐efficiency trade‐off.

Declining arthropod communities have recently gained a lot of attention, with climate and land-use change among the most frequently discussed drivers. Here, we focus on a seemingly underrepresented driver of arthropod community decline: biological invasions. For approximately 12 000 years, earthworms have been absent from wide parts of northern North America, but they have been re-introduced with dramatic consequences. Most studies investigating earthworm-invasion impacts focus on the belowground world, resulting in limited knowledge on aboveground-community changes. We present observational data on earthworm, plant and aboveground arthropod communities in 60 plots, distributed across areas with increasing invasion status (low, medium and high) in a Canadian forest. We analysed how earthworm-invasion status and biomass impact aboveground arthropod community abundance, biomass and species richness, and how earthworm impacts cascade across trophic levels. We sampled approximately 13 000 arthropods, dominated by Hemiptera, Diptera, Araneae, Thysanoptera and Hymenoptera. Total arthropod abundance, biomass and species richness declined significantly from areas of low to those with high invasion status, with reductions of 61, 27 and 18%, respectively. Structural equation models suggest that earthworms directly and indirectly impact arthropods across trophic levels. We show that earthworm invasion can alter aboveground multi-trophic arthropod communities and suggest that belowground invasions might be underappreciated drivers of aboveground arthropod decline.

Highlights • Cognitive-behavioural therapy (CBT) and motivational interviewing (MI) can be readily adapted for brief, minimally guided, online interventions. • Minimally guided online treatment is beneficial for hazardous drinking, mood difficulties, and quality of life in the short-term among young adults. • Strategies designed to increase treatment engagement will likely mitigate the risk of attrition in future programs. • Future versions of the Take Care of Me program are still needed to determine long-term effects and differential responses to treatment., Objective Many young adults struggle with comorbid alcohol misuse and emotional problems (i.e., depression and anxiety). However, there is currently a paucity of evidence-based, integrated, accessible treatment options for individuals with these comorbidities. The main goal of this study was to examine efficacy of a novel online, minimally guided, integrated program for comorbid alcohol misuse and emotional problems in young adults. Method: The study was an open-label two-arm RCT. Participants (N = 222, Mage = 24.6, 67.6% female) were randomized to one of two conditions: the Take Care of Me program (an 8-week, online integrated treatment condition consisting of 12 modules), or an online psychoeducational control condition. Intervention modules incorporated content based on principles of cognitive behavioral therapy and motivational interviewing. Participants completed assessment data at baseline, at the end of treatment (i.e., 8 weeks), and at follow-up (i.e., 24 weeks). Data were analyzed using generalized linear mixed models. Results: We observed that participants in the treatment condition showed larger reductions in depression, hazardous drinking, as well as increases in psychological quality of life and confidence at the end of treatment. We did not find group differences on total alcohol use at follow-up, but participants in the treatment group reduced their hazardous drinking and improved their quality of life at 24-week follow-up. Conclusions: Our study provides promising initial evidence for the first iteration of the comorbid alcohol misuse and emotional problems online program.

Background: Emerging adulthood is associated with heavy drinking. Despite overall heavy use, studies show considerable heterogeneity in emerging adult drinking habits. Lau-Barraco and colleagues (2016 b) identified three subtypes (high, moderate, low) of emerging adult heavy drinkers based on patterns of use across common drinking situations. Heavy situational drinkers had more alcohol problems, mental health symptoms, and coping/conformity motives for alcohol use.Objective: Our goal was to replicate and extend the aforementioned study, expecting to find the same subgroups, then examining whether certain risk factors predicted subgroup membership.Methods/Results: Undergraduates (N = 497) completed online self-report measures and a latent profile analysis (LPA) found support for three similar subtypes; low, "moderate" (higher endorsement of pleasant emotion/social pressure situations, relative to the low group), and high. Univariate ANOVAs, followed by pairwise comparisons, found that heavy situational drinkers scored highest on measures of alcohol problems, problem gambling, drug use, depression, and anxiety compared to the other two groups, and consistent with previous findings.Conclusions: This study showed that emerging adults who drink heavily across various situations are likely to engage in other addictive behaviors and struggle with mental health symptoms. Identifying one's personal risk factors and their riskiest drinking situations is critical for developing targeted intervention programs and increasing the understanding of the heterogeneous nature of drinking behaviors in emerging adults in Canada.

Supplemental Digital Content is available in the text., Introduction: Improving the discharge process is an area of focus throughout healthcare organizations. Capacity constraints, efficiency improvement, patient safety, and quality care are driving forces for many discharge process workgroups. Methods: Following the Pareto principle, we focused on improving the discharge process on the medical-surgical units that received the most patients admitted from the emergency department. Increased demand for medical-surgical beds, renovations, and diminished bed capacity made it imperative to improve efficiency using quality improvement techniques. A core team of frontline staff decreased the time between computer entry of discharge orders and patient’s departure from the unit to less than 60 minutes, with 80% compliance. The team developed a daily dashboard that detailed the process and outcome measures to create situational awareness and daily visual management. Additional observations of staff workflow uncovered excessive walking for printer use. Printers were placed at the point of use to reduce transport times. Next, using survey results provided by patients on discharge quality, a Treasure Map that aided with teach-back and Team Discharge were implemented to level the staff’s workload. Finally, physicians discharged patients earlier in the day. They standardized their discharge criteria to remove subjectivity from the discharge process and enable better team involvement. Results: After implementing 4 interventions, the average time between computer entry of discharge orders and patient’s departure from the unit decreased (94.26 versus 65.98 minutes; P < 0.001), simultaneously reducing our average length of stay from 5.62 to 4.81 days (P < 0.001). Conclusions: In conclusion, hardwiring proven interventions and complementing them with daily visual management led to significant, sustained results.

Three experiments were conducted to evaluate direct-fed microbial (DFM) supplementation on live performance, carcass characteristics, and fecal shedding of E. coli in feedlot steers. In Exp. 1, 400 steers (BW = 348 kg) were assigned to treatments: CON = lactose carrier only, BOV = P. freudenreichii (NP24) + L. acidophilus (NP51), BOVD = P. freudenreichii (NP24) + L. acidophilus (NP51), and COMB = BOV fed for the first 101 d on feed, followed by BOVD for the final 28 d prior to harvest. In Exp. 2 (n = 1800; BW = 354 kg) and Exp. 3 (n = 112; BW = 397 kg), steers were utilized in a randomized complete block design and assigned to DFM treatments using low dose and high dose, respectively. Fecal samples were collected prior to harvest and analyzed for E. coli serogroups. In Exp. 1, DFM reduced (P E. coli O157. Prevalence of O157 was reduced by BOVD supplementation in Exp. 2 and 3 (P E. coli O157 in positive samples was reduced in both experiments where enumeration was performed (P ≤ 0.02). Weighted mean differences across the three experiments were equal to a 33% reduction in the prevalence of E. coli O157:H7 in BOVD treated cattle. A significant reduction in prevalence of O26, O45, O103, and O121 was observed in Exp. 2 (P ≤ 0.03). These results indicate that high levels of L. acidophilus (NP51) may represent an effective pre-harvest food safety intervention to reduce fecal shedding of several E. coli serogroups.

Oceanic internal waves can be decomposed into an infinite set of modes, and the dominant internal mode 1 waves have been extensively investigated. Although mode 2 waves have been observed, they have not received comparable attention, especially the generation mechanisms. In this work, we examine the generation of mode 2 internal waves by the interaction of mode 1 waves with topography. We use a coupled linear long-wave theory with mode coupling through topography, combined with evolution using a Korteweg–de Vries model, to predict the mode 2 wave amplitude, in an ideal three-layer fluid model, in a smooth density stratification and in two realistic oceanic settings. We find that the mode 2 wave amplitude is usually much smaller than the incident mode 1 wave amplitude and is quite sensitive to the pycnocline thickness, topographic slope and background stratification.

In this study, we examine the transformation of a mode-1 internal solitary wave incident on a bottom step, and the consequent generation of mode-2 internal solitary waves. A linear long-wave theory...

One of the first significant developments in wildfire modeling research was to introduce heat flux as wildfire line intensity (kW·m–1). This idea could be adapted to using weather station measureme...

Problem drinking and gambling are addictive behaviours experienced by young adults and commonly occur with narcissism. Research has acknowledged two distinct forms of narcissism: grandiose and vulnerable. There has been work that has examined the relationship between grandiose and vulnerable narcissism and addictive behaviours, but it has been limited, particularly with vulnerable narcissism. Evidence suggests vulnerable narcissism, but not grandiose narcissism, is associated with greater negative affect. Accordingly, shame, a potent social emotion could be a mediator in the narcissism-addiction pathway. Shame has been implicated in both vulnerable narcissism and problem drinking and gambling. Thus, we hypothesized that shame would mediate the relationship between vulnerable narcissism and addictive behaviours. Young adults (N = 210) completed self-report baseline (Time 1) and 1-month follow-up (Time 2) assessments of shame, narcissism, problem drinking, and gambling. As predicted, those with elevated vulnerable narcissism at Time 1 had increased shame at Time 2, which predicted problem drinking and gambling at Time 2. This relationship was not observed for grandiose narcissism. Overall, our results suggest that feelings of shame are essential to understanding the vulnerable narcissism-addiction pathway, and an important consideration when designing clinical interventions for at-risk young adults.

Experiments and field observations have shown that there are at least two modes of behavior for river plumes. In many cases, the plume turns to the right (in the Northern Hemisphere) on leaving the river mouth and follows the direction of Kelvin-wave propagation. Alternatively, a “bulge” can form in the plume and a fraction of the outflow volume becomes trapped near the mouth. This paper discusses how bulge formation can be affected by the vorticity profile at the river mouth. Due to the image effect, regions of cyclonic vorticity tend to propagate rightwards, whereas regions of anticyclonic vorticity propagate leftward upon exit from the source. If an outflow consists of regions of cyclonic vorticity to the left of regions of anticyclonic vorticity, the two image effects are in competition. We explore this phenomenon using a quasi-geostrophic model with piecewise-constant potential vorticity, which allows the vorticity profile at the source to be set as part of the problem. We present analytic solutions valid in the source region and at the head of the plume and show that all of the outflow travels rightwards if and only if the region of cyclonic vorticity is dominant. The initial-value problem for the model is integrated numerically using the method of contour dynamics, and the full parameter space is explored. We find that if the cyclonic and anticyclonic contributions cancel, as in the experiments of Avicola and Huq (2003), then steady solutions are unstable and a bulge can form downstream of the river mouth.

Hill's vortex is a classical solution of the incompressible Euler equations which consists of an axisymmetric spherical region of constant vorticity matched to an irrotational external flow. This solution has been shown to be a member of a one-parameter family of steady vortex rings and as such is commonly used as a simple analytic model for a vortex ring. Here, we model the decay of a Hill's vortex in a weakly rotating flow due to the radiation of inertial waves. We derive analytic results for the modification of the vortex structure by rotational effects and the generated wave field using an asymptotic approach where the rotation rate, or inverse Rossby number, is taken to be small. Using this model, we predict the decay of the vortex speed and radius by combining the flux of vortex energy to the wave field with the conservation of peak vorticity. We test our results against numerical simulations of the full axisymmetric Navier–Stokes equations.

A simple model is presented for the evolution of a dipolar vortex propagating horizontally in a vertical-slice model of a weakly stratified inviscid atmosphere, following the model of Flierl & Haines (Phys. Fluids, vol. 6, 1994, pp. 3487–3497) for a modon on the -plane. The dipole is assumed to evolve to remain within the family of Lamb–Chaplygin dipoles but with varying radius and speed. The dipole loses energy and impulse through internal wave radiation. It is argued, and verified against numerical solutions of the full equations, that an appropriately defined centre vorticity for the dipole is closely conserved throughout the flow evolution. Combining conservation of centre vorticity with the requirement that the dipole energy loss balances the work done on the fluid by internal wave radiation gives a model that captures much of the observed dipole decay. Similar results are noted for a cylindrical dipole propagating along the axis of a rotating fluid when the dipole axis is perpendicular to the axis of rotation and for a spherical vortex propagating horizontally in a weakly stratified fluid. The model extends to fluids of small viscosity and so provides an estimate for the relative importance of wave drag and dissipation in dipole decay.

This paper studies the hydraulic control of continental shelf waves using an inviscid barotropic quasi-geostrophic model with piecewise-constant potential vorticity, in which the shelf is represented by a flat step of variable width. A coastal-intensified geostrophic current generates topographic Rossby waves, which can become critical at a local decrease in shelf width when the background current opposes Rossby wave propagation. That is, the shelfbreak perturbation permanently modifies the flow field over arbitrarily large distances and the flow transitions from subcritical to supercritical as it crosses the perturbation. Critically controlled flows also lead to the exchange of significant volumes of water between the shelf and the deep ocean. We derive the boundaries for which critical control occurs in terms of a Froude number and the dimensionless magnitude of the perturbation, and analyse the possible transitions between controlled and far-field flow. When first-order dispersive terms are included in the model, transitions are resolved by dispersive shock waves, which remain attached to the forcing region when the Froude number is close to the boundary for critical flow. Contour dynamic simulations show that the dispersive long-wave model captures the quantitative behaviour of the full quasi-geostrophic system for slowly varying shelves, and replicates the qualitative behaviour even when the long-wave parameter is order one.