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Warming temperatures are altering communities and trophic networks across Earth's ecosystems. While the overall influence of warming on food webs is often context-dependent, increasing temperatures are predicted to change communities in two fundamental ways: (1) by reducing average body size and (2) by increasing individual metabolic rates. These warming-induced changes have the potential to influence the distribution of food web fluxes, food web stability, and the relative importance of deterministic and stochastic ecological processes shaping community assembly. Here, we quantified patterns and the relative distribution of organic matter fluxes through stream food webs spanning a broad natural temperature gradient (5-27°C). We then related these patterns to species and community trait distributions of mean body size and population biomass turnover (P:B) within and across streams. We predicted that (1) communities in warmer streams would exhibit smaller body size and higher P:B and (2) organic matter fluxes within warmer communities would increasingly skew toward smaller, higher P:B populations. Across the temperature gradient, warmer communities were characterized by smaller body size (~9% per °C) and higher P:B (~7% faster turnover per °C) populations on average. Additionally, organic matter fluxes within warmer streams were increasingly skewed toward higher P:B populations, demonstrating that warming can restructure organic matter fluxes in both an absolute and relative sense. With warming, the relative distribution of organic matter fluxes was decreasingly likely to arise through the random sorting of species, suggesting stronger selection for traits driving high turnover with increasing temperature. Our study suggests that a warming world will favor energy fluxes through "smaller and faster" populations, and that these changes may be more predictable than previously thought., (© 2024 The Authors. Ecology published by Wiley Periodicals LLC on behalf of The Ecological Society of America.)

Objective: Virtual reality (VR) is a promising non-pharmacologic tool for managing health care anxiety. We assessed the feasibility and acceptability of a pre-operative VR intervention by adult patients and medical staff and measured anxiety in adult patients pre- and post-VR intervention., Study Design: We recruited 30 patients scheduled to undergo oral surgery and 8 medical staff as participants. The patients completed a verbal demographic survey and rated their anxiety before the VR intervention and at 1 minute and 2 minutes post-intervention. We administered the Acceptability of Intervention Measure to the patients to measure their perceptions of the VR intervention and the Feasibility of Intervention Measure to the medical staff to assess their perception of VR implementation. We performed an analysis of variance to compare pre-operative anxiety over time and assess demographic differences., Results: The patients showed high and consistent acceptability of the pre-operative use of VR among patients, but acceptability varied among medical staff. The patients experienced a statistically significant reduction of pre-operative anxiety (P = .003)., Conclusion: A brief VR pre-intervention is highly accepted by and very beneficial for patients undergoing oral surgery, positively affecting anxiety reduction. The perception of VR by health care providers needs to be explored to increase acceptability., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: Suicide prevention gatekeeping is a skill that may support community (retail) pharmacists in managing patients who present with suicide warning signs. A brief, virtual, case-based training intervention was tailored to the retail setting (Pharm-SAVES). To test training effectiveness, a randomized controlled trial (RCT) protocol was developed for use in pharmacies across four states., Objective: To introduce the trial protocol for assessing the effectiveness for increasing the proportion of staff who recognize patients displaying warning signs and self-report engaging in gatekeeping, including asking if the patient is considering suicide., Methods: This study uses a parallel cluster-randomized controlled trial to recruit 150 pharmacy staff in community pharmacies in four states with two groups (intervention and control). The control group completes Pharm-SAVES online suicide prevention gatekeeper training and all assessment surveys at baseline after training and at 1-month follow-up. The experimental group completes all control group training and assessments plus interactive video role-play patient cases., Conclusion: We hypothesize that compared to those in the control group, experimental group trainees exposed to the interactive video role play patient cases will be more likely to recognize warning signs in patient cases and self-report engaging in gatekeeping., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 Published by Elsevier Inc.)

Introduction: VA S.A.V.E. (Signs; Ask; Validate; Encourage/Expedite) is a gatekeeper training developed by the Department of Veterans Affairs (VA) that teaches individuals to identify and assist veterans at risk for suicide. Although VA S.A.V.E. has been widely disseminated, rigorous evaluation is lacking., Methods: In a pilot randomized controlled trial of a brief, video-based version of VA S.A.V.E., individuals were recruited through Facebook, randomized to VA S.A.V.E. versus an attention control condition, and completed 6-month follow-up. A subgroup (n = 15) completed interviews. We used a mixed methods framework to integrate quantitative and qualitative findings., Results: Among 214 participants, 61% were spouses/partners of veterans and 77% had prior suicide exposure. Sixty-seven percent (n = 68) of VA S.A.V.E. participants watched the entire video, and satisfaction and usability were highly rated. At 6-month follow-up, compared to the control group, the VA S.A.V.E. group had a higher proportion of participants use each gatekeeper behavior (66.7%-84.9% vs. 44.4%-77.1%), and used significantly more total gatekeeper behaviors (2.3 ± 0.9 vs. 1.8 ± 1.0; p = 0.01). Interviews supported positive reactions, learning, and behavior change from VA S.A.V.E., Conclusion: VA S.A.V.E. merits further investigation into its effectiveness as a brief, scalable gatekeeper training for suicide prevention in veterans., (© 2023 American Association of Suicidology. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.)

Ecosystem engineers modify habitats in ways that facilitate other community members by ameliorating harsh conditions. The strength of such facilitation is predicted to be influenced by both beneficiary traits and abiotic context. One key trait of animals that could control the strength of facilitation is beneficiary body size because it should determine how beneficiaries fit within and exploit stress ameliorating habitat modifications. However, few studies have measured how beneficiary body size relates to facilitation strength along environmental gradients. We examined how the strength of facilitation by net-spinning caddisflies on invertebrate communities in streams varied along an elevation gradient and based on traits of the invertebrate beneficiaries. We measured whether use of silk retreats as habitat concentrated invertebrate density and biomass compared to surrounding rock surface habitat and whether the use of retreat habitat varied across body sizes of community members along the gradient. We found that retreats substantially concentrated the densities of a diversity of taxa including eight different Orders, and this effect was greatest at high elevations. Caddisfly retreats also concentrated invertebrate biomass more as elevation increased. Body size of invertebrates inhabiting retreats was lower than that of surrounding rock habitats at low elevation sites, however, body size between retreats and rocks converged at higher elevation sites. Additionally, the body size of invertebrates found in retreats varied within and across taxa. Specifically, caddisfly retreats functioned as a potential nursery for taxa with large maximal body sizes. However, the patterns of this taxon-specific nursery effect were not influenced by elevation unlike the patterns observed based on community-level body size. Collectively, our results indicate that invertebrates use retreats in earlier life stages or when they are smaller in body size independent of life stage. Furthermore, our analysis suggests that facilitation strength intensifies as elevation increases within stream invertebrate communities. Further consideration of how trait variation and environmental gradients interact to determine the strength and direction of biotic interactions will be important as species ranges and environmental conditions continue to shift., (© 2023 The Authors. Journal of Animal Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society.)

Ecosystem engineers can generate hotspots of ecological structure and function by facilitating the aggregation of both resources and consumers. However, nearly all examples of such engineered hotspots come from long-lived foundation species, such as marine and freshwater mussels, intertidal cordgrasses, and alpine cushion plants, with less attention given to small-bodied and short-lived animals. Insects often have rapid life cycles and high population densities and are among the most diverse and ubiquitous animals on earth. Although these taxa have the potential to generate hotspots and heterogeneity comparable to that of foundation species, few studies have examined this possibility. We conducted a mesocosm experiment to examine the degree to which a stream insect ecosystem engineer, the net-spinning caddisfly (Tricoptera:Hydropsychidae), creates hotspots by facilitating invertebrate community assembly. Our experiment used two treatments: (1) stream benthic habitat with patches of caddisfly engineers present and (2) a control treatment with no caddisflies present. We show that compared to controls, caddisflies increased local resource availability measured as particulate organic matter (POM) by 43%, ecosystem respiration (ER) by 70%, and invertebrate density, biomass, and richness by 96%, 244%, and 72%, respectively. These changes resulted in increased spatial variation of POM by 25%, invertebrate density by 76%, and ER by 29% compared to controls, indicating a strong effect of caddisflies on ecological heterogeneity. We found a positive relationship between invertebrate density and ammonium concentration in the caddisfly treatment, but no such relationship in the control, indicating that either caddisflies themselves or the invertebrate aggregations they create increased nutrient availability. When accounting for the amount of POM, caddisfly treatments increased invertebrate density by 48% and richness by 40% compared to controls, suggesting that caddisflies may also enhance the nutritional quality of resources for the invertebrate assemblage. The caddisfly treatment also increased the rate of ecosystem respiration as a function of increasing POM compared to the control. Our study demonstrates that insect ecosystem engineers can generate heterogeneity by concentrating local resources and consumers, with consequences for carbon and nutrient cycling., (© 2023 The Ecological Society of America.)

Introduction: Pharmacists are one of the most accessible health professionals in the United States, who, with training, may serve as gatekeepers who recognize suicide warning signs and refer at-risk individuals to care. Our objective was to codesign a 30-min online gatekeeper training module (Pharm-SAVES) specifically for community pharmacy staff., Methods: Over a period of 8 months, a nine-member pharmacy staff stakeholder panel and the Finger Lakes (New York) Veterans Research Engagement Review Board each worked with the study team to codesign Pharm-SAVES. Formative data from previous interviews with community pharmacists were presented to the panels and guided website development., Results: Four key topics were identified for brief skills-based modules that could be delivered asynchronously online. To help pharmacy staff understand their opportunities as gatekeepers in suicide prevention, statistics and statements from the Joint Commission and pharmacy professional organizations were highlighted in Module 1 ('Why Me?'). Module 2 ('What can I do?') presents the five gatekeeping steps (SAVES): (1) Recognize suicide warning Signs, (2) Ask if someone is considering suicide, (3) Validate feelings, (4) Expedite referral, and (5) Set a reminder to follow-up. Module 3 ('How does it work?') provides three video scenarios modeling SAVES steps and two interactive video cases for participant practice. Module 3 demonstrates use of the 24/7 National Suicide Prevention Lifeline, including the DOD/VA Crisis Line. Module 4 (Resources) includes links to national resources and a searchable zip code-based provider directory. Pharm-SAVES was codesigned with pharmacy and veteran stakeholders to deliver brief, skills-focused, video-based interactive training that is feasible to implement in busy community pharmacy settings., Conclusion: Pharm-SAVES is a brief, online suicide prevention gatekeeper training program codesigned by researchers, community pharmacy and veteran stakeholders. By actively engaging stakeholders at each stage of the design process, we were able to create training content that was not only realistic but more relevant to the needs of pharmacy staff. Currently, Pharm-SAVES is being evaluated in a pilot randomized controlled trial for changes in pharmacy staff suicide prevention communication behaviors., Patient or Public Contribution: Stakeholder engagement was purposefully structured to engage pharmacy staff and pharmacy consumers, with multiple opportunities for study contribution. Likewise, the involvement of patient/public contribution was paramount in study design and overall development of our study team., (© 2023 The Authors. Health Expectations published by John Wiley & Sons Ltd.)

Purpose: Virtual reality (VR) is considered a nonpharmacological intervention to manage pain and anxiety for different procedures. We aimed to review the literature about the role of VR in reducing pain and anxiety in surgical procedures performed in the oral cavity., Methods: A literature review was conducted using Medline and Embase with no restrictions on language or publication date. Our inclusion criteria were articles related to the use of VR to manage perioperative pain and anxiety on procedures in the oral cavity., Results: Twenty-seven articles met the inclusion criteria. The number of publications increased significantly from 2 studies between 2000-2010 to 25 between 2011 and 2021. Of the 27 included studies, 22 (81.4%) studied patients undergoing dental procedures, and 5 (18.5%) in oral and maxillofacial surgery (OMS). There was heterogeneity in the VR software used in the different studies. Thirteen studies (41.9%) evaluated self or observational assessments of pain and anxiety. Pain alone was evaluated in 9 studies (29%) and anxiety alone in 8 studies (25.8%). Also, 6 studies (19.3%) evaluated physiological parameters such as heart rate and respiratory rate as objective measures of pain and anxiety. In oral surgery studies, VR was effective at reducing acute pain, fear, and anxiety levels., Conclusions: There is a paucity of research in OMS compared to dentistry. Given that this specialty involves highly stimulating and anxiety-provoking procedures, OMS could benefit from VR intervention for improved patient care., (Copyright © 2022 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

Purpose: Suicide risk is higher among violence-involved individuals. Intimate Partner Violence hotline workers are a critical source of support and can potentially be suicide prevention champions. Our primary goal was to examine the effectiveness of disseminating a free, online IPV-Suicide Prevention curriculum, via a randomized control trial, to hotline workers in ten states with the highest suicide and IPV homicide rates., Method: We divided the country into five regions and, based on criterion, chose two states in each region to randomize into the two arms of the study. We examined training participation and engagement between the two approaches: (1) 'dissemination as usual' (control) using a National Domestic Violence Hotline email and a postcard to state/county IPV directors, versus (2) 'enhanced dissemination' (intervention) using a four-point touch method (postcard, phone call, email, and letter) to 'drive' participation., Results: Participation increased in the intervention arm as approaches became more personal (i.e., email and phone calls vs. letters). Results indicate that traditional dissemination strategies such as email announcements and invitations are not as effective as varied and multiple touchpoints for IPV hotline staff., Conclusion: Successful dissemination strategies to promote digital training should consider the value added by personalized connection. Future research is needed to understand how to offer effective and efficient web-based training to those providing IPV and child abuse services., Competing Interests: Conflict of InterestsNone., (© The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2023, Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

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., (© 2022 The Authors. Global Change Biology published by John Wiley & Sons Ltd.)

Objective: Almost half of individuals who die by suicide have had contact with primary care (PC) services within 1 month of their death. PC providers must be able to assess and manage patients' suicidal ideation, intent, and behaviors. When didactic training is provided to providers, it is assumed that their requisite skills are well developed. The current study assessed observed skills following high-quality online didactics., Method: Medical residents and nurse practitioner (NP) trainees (n = 127) participated in online didactic training as part of their education program, followed by a standardized patient interaction conducted to assess demonstrated suicide prevention skills (i.e., assessment of risk factors, protective factors, suicidal ideation and behavior, safety planning)., Results: Participants demonstrated only about 50% of the possible total skills in most domains and were least competent in assessing potential risk for suicide. Regression analyses showed that residents were rated significantly higher than NPs on observed skills. Personal experience with suicide was not associated with any observed skills. Baseline knowledge scores were positively associated with some skills while elapsed days since completion of didactics were negatively associated with skills., Conclusions: Didactics were insufficient for building suicide-specific assessment skills among physicians and nurses in advanced training., (© 2022 The American Association of Suicidology.)

Background: Studies of suicide prevention gatekeeper trainings (GKT) show temporary enhancements in short-term behavioral outcomes and limited enhancements in intermediate behavioral outcomes. Aims: We aimed to examine the impact of two training enhancements (role-play and booster) on intermediate GKT outcomes. Method: The study used a factorial randomized controlled design to assign participants to one of four groups. Three indicators of gatekeeper behavior at 6-month follow-up were the primary outcomes of interest. We used propensity score-based techniques to address observed imbalances. Results: At 6 months, among participants assigned to role-play, a significantly larger proportion of those assigned to booster performed identifications and referrals followed by a notification to the referral source, and followed by escorting the youth to the resource. Limitations: While observed imbalances were addressed, unobserved differences may persist. The validity of self-reported indicators to measure actual behavior remains unknown. Conclusion: Results suggest that active learning strategies can, in combination, enhance the effectiveness of trainings. The strategies seem to increase the comprehensiveness of gatekeeper behaviors.

Objective: To develop an online suicide prevention gatekeeper training program to prepare community pharmacy staff to communicate with patients who exhibit warning signs of suicide., Method: A convenience sample of 17 community pharmacy staff members completed a 1-hr semi-structured interview during which they viewed content from an existing gatekeeper training program and provided suggestions for improvement. Once thematic saturation was achieved, interviews were digitally recorded, transcribed, and analyzed by two independent coders who reached consensus on the themes present in each transcript., Results: Participants noted barriers to communicating about suicide, including lack of time and privacy, discomfort with using the word "suicide" and limited referral options. Participants wanted gatekeeper training to include local suicide prevention referral resources, take less than 30 min to complete, and incorporate 3-4 realistic role play scenarios, including a phone interaction., Conclusions: Many environmental, interpersonal, and individual-level barriers complicate pharmacy staff members' ability to act as gatekeepers and communicate about suicide with at-risk patients. To maximize the public health impact of pharmacy staff, skills-based training on how to identify, communicate with, and refer at-risk patients is needed. Gatekeeper training should model brief, realistic interactions with patients and provide pharmacy staff with local referral resources., (© 2020 The American Association of Suicidology.)

Tracking carbon (C) flow through ecosystems requires quantification of myriad biophysical processes, including C routing through microbial and metazoan food webs. Yet detailed organic matter budgets are rarely combined with simultaneous measurement of C flows supporting microbial and animal production. Here, we synthesize concurrent data sets on organic matter, microbes, and macroinvertebrates from two detritus-based stream ecosystems, one of which was subject to experimental nitrogen (N) and phosphorus (P) enrichment. Our synthesis provides new insights into C flow through forest stream ecosystems. Over 3 yr, the reference stream showed a striking balance of inputs and outputs, with a mean surplus of only 7 g C·m -2 ·yr -1 (~1% of annual inputs), presumably stored in sediments as fine particulate organic matter (FPOM). In contrast, N and P enrichment over 2 yr resulted in severe deficits of C (-576 g C·m -2 ·yr -1 or ~170% of annual inputs), a shortfall presumably met by stored C. Our data set provides an ecosystem-based estimate of the fate of forest litter C at ambient nutrient concentrations: 6.2% was leached as dissolved organic C, 40.6% and 8.5% flowed to litter-associated fungi and bacteria, respectively, 7.5% was consumed by macroinvertebrates, 1.8% was exported as coarse particles, and the remainder (35.4%) was presumably fragmented by biophysical processes. Our calculations also allowed an estimate of inputs into the heterogeneous FPOM pool, which is otherwise difficult to obtain. At naturally low nutrient concentrations, 50.7% was derived from fragmented litter, 39.1% from microbial biomass (mostly fungal), and 10.2% from macroinvertebrate egesta. Nutrient addition drove large changes in C fluxes in the experimental stream, especially in flows of leaf litter to fungi (×1.7 pretreatment) and macroinvertebrates (×2.7), and of FPOM to hydrologic export (×2.6). Our results underscore the key roles of both microbes and metazoans in controlling C flow through detritus-based ecosystems, as well as how release from persistent nutrient limitation may perturb steady-state conditions of C inputs vs. outputs. Our analysis also suggests areas for future research, including assessing the relative importance of stored vs. recycled C in fueling detrital food webs subject to altered nutrient regimes and other global-change drivers., (© 2020 by the Ecological Society of America.)

Background and Objectives: One-third of individuals who die by suicide had primary care contact in the preceding month. Primary care trainees need engaging and effective suicide prevention training that can be delivered within tight time and resource constraints. However, training is currently scarce and its effectiveness unknown. The objective of this study was to assess learner engagement, learning, self-efficacy, and perceived ability to transfer training to practice from brief video-based modules centered around visual concept mapping of suicide prevention practices., Methods: We assigned 127 primary care trainees 21 brief instructional videos to watch. We analyzed engagement by monitoring the proportion of learners who began each video and the proportion of the video watched. We assessed knowledge and self-efficacy pre- and posttraining. Learners provided feedback on satisfaction with modules and ability to transfer training to practice., Results: Engagement was high, with most learners watching most of each video (mean=83.2%). Increase in knowledge was large (t(131 df)=19.91, P<.001). Confidence in ability to manage suicide risk rose significantly (t(131 df)=16.31, P<.001). Perception of ability to transfer training to practice was moderate. Satisfaction with modules was high. Feedback asked for patient scenarios and practical skills examples., Conclusions: This training successfully engaged primary health care trainees in suicide prevention education. Training transfer will be improved by adding skill demonstrations, a suicide attempt survivor perspective, and a memorable framework to assist implementation of knowledge. A new iteration incorporating these improvements is under evaluation. Variants for other health care settings are under development.

Mercury (Hg) biomagnification in aquatic food webs is a global concern; yet, the ways species traits and interactions mediate these fluxes remain poorly understood. Few pathways dominated Hg flux in the Colorado River despite large spatial differences in food web complexity, and fluxes were mediated by one functional trait, predation resistance. New Zealand mudsnails are predator resistant and a trophic dead end for Hg in food webs we studied. Fishes preferred blackflies, which accounted for 56 to 80% of Hg flux to fishes, even where blackflies were rare. Food web properties, i.e., match/mismatch between insect production and fish consumption, governed amounts of Hg retained in the river versus exported to land. An experimental flood redistributed Hg fluxes in the simplified tailwater food web, but not in complex downstream food webs. Recognizing that species traits, species interactions, and disturbance mediate contaminant exposure can improve risk management of linked aquatic-terrestrial ecosystems., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).)

Climate warming is predicted to alter routing and flows of energy through food webs because of the critical and varied effects of temperature on physiological rates, community structure, and trophic dynamics. Few studies, however, have experimentally assessed the net effect of warming on energy flux and food web dynamics in natural intact communities. Here, we test how warming affects energy flux and the trophic basis of production in a natural invertebrate food web by experimentally heating a stream reach in southwest Iceland by ~4°C for 2 yr and comparing its response to an unheated reference stream. Previous results from this experiment showed that warming led to shifts in the structure of the invertebrate assemblage, with estimated increases in total metabolic demand but no change in annual secondary production. We hypothesized that elevated metabolic demand and invariant secondary production would combine to increase total consumption of organic matter in the food web, if diet composition did not change appreciably with warming. Dietary composition of primary consumers indeed varied little between streams and among years, with gut contents primarily consisting of diatoms (72.9%) and amorphous detritus (19.5%). Diatoms dominated the trophic basis of production of primary consumers in both study streams, contributing 79-86% to secondary production. Although warming increased the flux of filamentous algae within the food web, total resource consumption did not increase as predicted. The neutral net effect of warming on total energy flow through the food web was a result of taxon-level variation in responses to warming, a neutral effect on total invertebrate production, and strong trophic redundancy within the invertebrate assemblage. Thus, food webs characterized by a high degree of trophic redundancy may be more resistant to the effects of climate warming than those with more diverse and specialized consumers., (© 2019 by the Ecological Society of America.)

Secondary production, the growth of new heterotrophic biomass, is a key process in aquatic and terrestrial ecosystems that has been carefully measured in many flowing water ecosystems. We combine structural equation modeling with the first worldwide dataset on annual secondary production of stream invertebrate communities to reveal core pathways linking air temperature and precipitation to secondary production. In the United States, where the most extensive set of secondary production estimates and covariate data were available, we show that precipitation-mediated, low-stream flow events have a strong negative effect on secondary production. At larger scales (United States, Europe, Central America, and Pacific), we demonstrate the significance of a positive two-step pathway from air to water temperature to increasing secondary production. Our results provide insights into the potential effects of climate change on secondary production and demonstrate a modeling framework that can be applied across ecosystems.

Background: Suicide is a national public health crisis and a critical patient safety issue. It is the 10th leading cause of death overall and the second leading cause of death among adolescents and young adults (15-34 years old). Research shows 80% of youth who died by suicide saw their primary care provider within the year of their death. It is imperative that primary care providers develop the knowledge and skills to talk with patients about distress and suicidal thoughts, and to assess and respond in the context of the ongoing patient - primary care provider relationship., Methods: This study examines the effectiveness of simulation on suicide prevention training for providers-in-training by comparing two conditions: 1) a control group that receives online teaching on suicide prevention in primary care via brief online videos and 2) an experimental group that includes the same online teaching videos plus two standardized patient (SP) interactions (face-to-face and telehealth, presentation randomized). All SP interactions are video-recorded. The primary analysis is a comparison of the two groups' suicide prevention skills using an SP "test case" at 6-month follow-up., Discussion: The primary research question examines the impact of practice (through SP simulation) over and above online teaching alone on suicide prevention skills demonstrated at follow-up. We will assess moderators of outcomes, differences among SP simulations (i.e., face-to-face vs. telehealth modalities), and whether the experimental group's suicide prevention skills improve over the three SP experiences., Trial Registration: The study was registered on Clinical Trials Registry ( clinicaltrials.gov ) on December 14, 2016. The Trial Registration Number is NCT02996344 .

River ecosystems receive and process vast quantities of terrestrial organic carbon, the fate of which depends strongly on microbial activity. Variation in and controls of processing rates, however, are poorly characterized at the global scale. In response, we used a peer-sourced research network and a highly standardized carbon processing assay to conduct a global-scale field experiment in greater than 1000 river and riparian sites. We found that Earth's biomes have distinct carbon processing signatures. Slow processing is evident across latitudes, whereas rapid rates are restricted to lower latitudes. Both the mean rate and variability decline with latitude, suggesting temperature constraints toward the poles and greater roles for other environmental drivers (e.g., nutrient loading) toward the equator. These results and data set the stage for unprecedented "next-generation biomonitoring" by establishing baselines to help quantify environmental impacts to the functioning of ecosystems at a global scale.

Climate warming is affecting the structure and function of river ecosystems, including their role in transforming and transporting carbon (C), nitrogen (N), and phosphorus (P). Predicting how river ecosystems respond to warming has been hindered by a dearth of information about how otherwise well-studied physiological responses to temperature scale from organismal to ecosystem levels. We conducted an ecosystem-level temperature manipulation to quantify how coupling of stream ecosystem metabolism and nutrient uptake responded to a realistic warming scenario. A ~3.3°C increase in mean water temperature altered coupling of C, N, and P fluxes in ways inconsistent with single-species laboratory experiments. Net primary production tripled during the year of experimental warming, while whole-stream N and P uptake rates did not change, resulting in 289% and 281% increases in autotrophic dissolved inorganic N and P use efficiency (UE), respectively. Increased ecosystem production was a product of unexpectedly large increases in mass-specific net primary production and autotroph biomass, supported by (i) combined increases in resource availability (via N mineralization and N 2 fixation) and (ii) elevated resource use efficiency, the latter associated with changes in community structure. These large changes in C and nutrient cycling could not have been predicted from the physiological effects of temperature alone. Our experiment provides clear ecosystem-level evidence that warming can shift the balance between C and nutrient cycling in rivers, demonstrating that warming will alter the important role of in-stream processes in C, N, and P transformations. Moreover, our results reveal a key role for nutrient supply and use efficiency in mediating responses of primary producers to climate warming., (© 2017 John Wiley & Sons Ltd.)

Objective: The relationship between trainer fidelity during a two-day suicide prevention program for counselors at crisis centers and counselors' behaviors during calls from individuals with suicidal thoughts was examined., Methods: The study used two data sets from a randomized control trial of a suicide prevention program delivered by counselors at 17 crisis centers who had previously received training (train-the-trainer [TTT] approach). One data set examined counselors' behaviors by silently monitoring calls (N=764) to the crisis lines, and one assessed adherence to manual content and competence in delivery among trainers (N=34) by coding training videotapes. Multilevel modeling was used to account for nested data., Results: Use of recommended behaviors by counselors was primarily related to trainers' competence in delivery of the program rather than adherence to the program content., Conclusions: Trainer selection for competence may be particularly critical for group-based TTT programs involving experienced counselors and the use of experiential activities.

Although aquatic ecologists and biogeochemists are well aware of the crucial importance of ecosystem functions, i.e., how biota drive biogeochemical processes and vice-versa, linking these fields in conceptual models is still uncommon. Attempts to explain the variability in elemental cycling consequently miss an important biological component and thereby impede a comprehensive understanding of the underlying processes governing energy and matter flow and transformation. The fate of multiple chemical elements in ecosystems is strongly linked by biotic demand and uptake; thus, considering elemental stoichiometry is important for both biogeochemical and ecological research. Nonetheless, assessments of ecological stoichiometry (ES) often focus on the elemental content of biota rather than taking a more holistic view by examining both elemental pools and fluxes (e.g., organismal stoichiometry and ecosystem process rates). ES theory holds the promise to be a unifying concept to link across hierarchical scales of patterns and processes in ecology, but this has not been fully achieved. Therefore, we propose connecting the expertise of aquatic ecologists and biogeochemists with ES theory as a common currency to connect food webs, ecosystem metabolism, and biogeochemistry, as they are inherently concatenated by the transfer of carbon, nitrogen, and phosphorous through biotic and abiotic nutrient transformation and fluxes. Several new studies exist that demonstrate the connections between food web ecology, biogeochemistry, and ecosystem metabolism. In addition to a general introduction into the topic, this paper presents examples of how these fields can be combined with a focus on ES. In this review, a series of concepts have guided the discussion: (1) changing biogeochemistry affects trophic interactions and ecosystem processes by altering the elemental ratios of key species and assemblages; (2) changing trophic dynamics influences the transformation and fluxes of matter across environmental boundaries; (3) changing ecosystem metabolism will alter the chemical diversity of the non-living environment. Finally, we propose that using ES to link nutrient cycling, trophic dynamics, and ecosystem metabolism would allow for a more holistic understanding of ecosystem functions in a changing environment.

A central question at the interface of food-web and climate change research is how secondary production, or the formation of heterotroph biomass over time, will respond to rising temperatures. The metabolic theory of ecology (MTE) hypothesizes the temperature-invariance of secondary production, driven by matched and opposed forces that reduce biomass of heterotrophs while increasing their biomass turnover rate (production : biomass, or P:B) with warming. To test this prediction at the whole community level, we used a geothermal heat exchanger to experimentally warm a stream in southwest Iceland by 3.8°C for two years. We quantified invertebrate community biomass, production, and P : B in the experimental stream and a reference stream for one year prior to warming and two years during warming. As predicted, warming had a neutral effect on community production, but this result was not driven by opposing effects on community biomass and P:B. Instead, warming had a positive effect on both the biomass and production of larger-bodied, slower-growing taxa (e.g., larval black flies, dipteran predators, snails) and a negative effect on small-bodied taxa with relatively high growth rates (e.g., ostracods, larval chironomids). We attribute these divergent responses to differences in thermal preference between small- vs. large-bodied taxa. Although metabolic demand vs. resource supply must ultimately constrain community production, our results highlight the potential for idiosyncratic community responses to warming, driven by variation in thermal preference and body size within regional species pools., (© 2017 by the Ecological Society of America.)

How ecological communities respond to predicted increases in temperature will determine the extent to which Earth's biodiversity and ecosystem functioning can be maintained into a warmer future. Warming is predicted to alter the structure of natural communities, but robust tests of such predictions require appropriate large-scale manipulations of intact, natural habitat that is open to dispersal processes via exchange with regional species pools. Here, we report results of a two-year whole-stream warming experiment that shifted invertebrate assemblage structure via unanticipated mechanisms, while still conforming to community-level metabolic theory. While warming by 3.8 °C decreased invertebrate abundance in the experimental stream by 60% relative to a reference stream, total invertebrate biomass was unchanged. Associated shifts in invertebrate assemblage structure were driven by the arrival of new taxa and a higher proportion of large, warm-adapted species (i.e., snails and predatory dipterans) relative to small-bodied, cold-adapted taxa (e.g., chironomids and oligochaetes). Experimental warming consequently shifted assemblage size spectra in ways that were unexpected, but consistent with thermal optima of taxa in the regional species pool. Higher temperatures increased community-level energy demand, which was presumably satisfied by higher primary production after warming. Our experiment demonstrates how warming reassembles communities within the constraints of energy supply via regional exchange of species that differ in thermal physiological traits. Similar responses will likely mediate impacts of anthropogenic warming on biodiversity and ecosystem function across all ecological communities., (© 2016 John Wiley & Sons Ltd.)

Animals can be important in modulating ecosystem-level nutrient cycling, although their importance varies greatly among species and ecosystems. Nutrient cycling rates of individual animals represent valuable data for testing the predictions of important frameworks such as the Metabolic Theory of Ecology (MTE) and ecological stoichiometry (ES). They also represent an important set of functional traits that may reflect both environmental and phylogenetic influences. Over the past two decades, studies of animal-mediated nutrient cycling have increased dramatically, especially in aquatic ecosystems. Here we present a global compilation of aquatic animal nutrient excretion rates. The dataset includes 10,534 observations from freshwater and marine animals of N and/or P excretion rates. These observations represent 491 species, including most aquatic phyla. Coverage varies greatly among phyla and other taxonomic levels. The dataset includes information on animal body size, ambient temperature, taxonomic affiliations, and animal body N:P. This data set was used to test predictions of MTE and ES, as described in Vanni and McIntyre (2016; Ecology DOI: 10.1002/ecy.1582)., (© 2017 by the Ecological Society of America.)

Although much effort has been devoted to quantifying how warming alters carbon cycling across diverse ecosystems, less is known about how these changes are linked to the cycling of bioavailable nitrogen and phosphorus. In freshwater ecosystems, benthic biofilms (i.e. thin films of algae, bacteria, fungi, and detrital matter) act as biogeochemical hotspots by controlling important fluxes of energy and material. Understanding how biofilms respond to warming is thus critical for predicting responses of coupled elemental cycles in freshwater systems. We developed biofilm communities in experimental streamside channels along a gradient of mean water temperatures (7.5-23.6 °C), while closely maintaining natural diel and seasonal temperature variation with a common water and propagule source. Both structural (i.e. biomass, stoichiometry, assemblage structure) and functional (i.e. metabolism, N2 -fixation, nutrient uptake) attributes of biofilms were measured on multiple dates to link changes in carbon flow explicitly to the dynamics of nitrogen and phosphorus. Temperature had strong positive effects on biofilm biomass (2.8- to 24-fold variation) and net ecosystem productivity (44- to 317-fold variation), despite extremely low concentrations of limiting dissolved nitrogen. Temperature had surprisingly minimal effects on biofilm stoichiometry: carbon:nitrogen (C:N) ratios were temperature-invariant, while carbon:phosphorus (C:P) ratios declined slightly with increasing temperature. Biofilm communities were dominated by cyanobacteria at all temperatures (>91% of total biovolume) and N2 -fixation rates increased up to 120-fold between the coldest and warmest treatments. Although ammonium-N uptake increased with temperature (2.8- to 6.8-fold variation), the much higher N2 -fixation rates supplied the majority of N to the ecosystem at higher temperatures. Our results demonstrate that temperature can alter how carbon is cycled and coupled to nitrogen and phosphorus. The uncoupling of C fixation from dissolved inorganic nitrogen supply produced large unexpected changes in biofilm development, elemental cycling, and likely downstream exports of nutrients and organic matter., (© 2015 John Wiley & Sons Ltd.)

Introduction of non-native species is a leading threat to global aquatic biodiversity. Competition between native and non-native species is often influenced by changes in suitable habitat or food availability. We investigated diet breadth and degree of trophic niche overlap for a fish assemblage of native and non-native species inhabiting a shallow, high elevation lake system. This assemblage includes one of the last remaining post-glacial endemic populations of adfluvial Arctic grayling (Thymallus arcticus) in the contiguous United States. We examined gut contents and stable isotope values of fish taxa in fall and spring to assess both short- (days) and long-term (few months) changes in trophic niches. We incorporate these short-term (gut contents) data into a secondary isotope analysis using a Bayesian statistical framework to estimate long-term trophic niche. Our data suggest that in this system, Arctic grayling share both a short- and long-term common food base with non-native trout of cutthroat x rainbow hybrid species (Oncorhynchus clarkia bouvieri x Oncorhynchus mykiss) and brook trout (Salvelinus fontinalis). In addition, trophic niche overlap among Arctic grayling, hybrid trout, and brook trout appeared to be stronger during spring than fall. In contrast, the native species of Arctic grayling, burbot (Lota lota), and suckers (Catostomus spp.) largely consumed different prey items. Our results suggest strong seasonal differences in trophic niche overlap among Arctic grayling and non-native trout, with a potential for greatest competition for food during spring. We suggest that conservation of endemic Arctic grayling in high-elevation lakes will require recognition of the potential for coexisting non-native taxa to impede well-intentioned recovery efforts.

Mercury (Hg) and selenium (Se) biomagnify in aquatic food webs and are toxic to fish and wildlife. The authors measured Hg and Se in organic matter, invertebrates, and fishes in the Colorado River food web at sites spanning 387 river km downstream of Glen Canyon Dam (AZ, USA). Concentrations were relatively high among sites compared with other large rivers (mean wet wt for 6 fishes was 0.17-1.59 μg g(-1) Hg and 1.35-2.65 μg g(-1) Se), but consistent longitudinal patterns in Hg or Se concentrations relative to the dam were lacking. Mercury increased (slope = 0.147) with δ(15) N, a metric of trophic position, indicating biomagnification similar to that observed in other freshwater systems. Organisms regularly exceeded exposure risk thresholds for wildlife and humans (6-100% and 56-100% of samples for Hg and Se, respectfully, among risk thresholds). In the Colorado River, Grand Canyon, Hg and Se concentrations pose exposure risks for fish, wildlife, and humans, and the findings of the present study add to a growing body of evidence showing that remote ecosystems are vulnerable to long-range transport and subsequent bioaccumulation of contaminants. Management of exposure risks in Grand Canyon will remain a challenge, as sources and transport mechanisms of Hg and Se extend far beyond park boundaries., (© 2015 SETAC.)

Variation in resource supply can cause variation in temperature dependences of metabolic processes (e.g., photosynthesis and respiration). Understanding such divergence is particularly important when using metabolic theory to predict ecosystem responses to climate warming. Few studies, however, have assessed the effect of temperature-resource interactions on metabolic processes, particularly in cases where the supply of limiting resources exhibits temperature dependence. We investigated the responses of biomass accrual, gross primary production (GPP), community respiration (CR), and N2 fixation to warming during biofilm development in a streamside channel experiment. Areal rates of GPP, CR, biomass accrual, and N2 fixation scaled positively with temperature, showing a 32- to 71-fold range across the temperature gradient (approximately 7 degrees-24 degrees C). Areal N2-fixation rates exhibited apparent activation energies (1.5-2.0 eV; 1 eV = approximately 1.6 x 10(-19) J) approximating the activation energy of the nitrogenase reaction. In contrast, mean apparent activation energies for areal rates of GPP (2.1-2.2 eV) and CR (1.6-1.9 eV) were 6.5- and 2.7-fold higher than estimates based on metabolic theory predictions (i.e., 0.32 and 0.65 eV, respectively) and did not significantly differ from the apparent activation energy observed for N2 fixation. Mass-specific activation energies for N2 fixation (1.4-1.6 eV), GPP (0.3-0.5 eV), and CR (no observed temperature relationship) were near or lower than theoretical predictions. We attribute the divergence of areal activation energies from those predicted by metabolic theory to increases in N2 fixation with temperature, leading to amplified temperature dependences of biomass accrual and areal rates of GPP and R. Such interactions between temperature dependences must be incorporated into metabolic models to improve predictions of ecosystem responses to climate change.

Temperature and nutrient availability play key roles in controlling the pathways and rates at which energy and materials move through ecosystems. These factors have also changed dramatically on Earth over the past century as human activities have intensified. Although significant effort has been devoted to understanding the role of temperature and nutrients in isolation, less is known about how these two factors interact to influence ecological processes. Recent advances in ecological stoichiometry and metabolic ecology provide a useful framework for making progress in this area, but conceptual synthesis and review are needed to help catalyze additional research. Here, we examine known and potential interactions between temperature and nutrients from a variety of physiological, community, and ecosystem perspectives. We first review patterns at the level of the individual, focusing on four traits--growth, respiration, body size, and elemental content--that should theoretically govern how temperature and nutrients interact to influence higher levels of biological organization. We next explore the interactive effects of temperature and nutrients on populations, communities, and food webs by synthesizing information related to community size spectra, biomass distributions, and elemental composition. We use metabolic theory to make predictions about how population-level secondary production should respond to interactions between temperature and resource supply, setting up qualitative predictions about the flows of energy and materials through metazoan food webs. Last, we examine how temperature-nutrient interactions influence processes at the whole-ecosystem level, focusing on apparent vs. intrinsic activation energies of ecosystem processes, how to represent temperature-nutrient interactions in ecosystem models, and patterns with respect to nutrient uptake and organic matter decomposition. We conclude that a better understanding of interactions between temperature and nutrients will be critical for developing realistic predictions about ecological responses to multiple, simultaneous drivers of global change, including climate warming and elevated nutrient supply., (© 2014 John Wiley & Sons Ltd.)

Understanding and predicting how global warming affects the structure and functioning of natural ecosystems is a key challenge of the 21st century. Isolated laboratory and field experiments testing global change hypotheses have been criticized for being too small-scale and overly simplistic, whereas surveys are inferential and often confound temperature with other drivers. Research that utilizes natural thermal gradients offers a more promising approach and geothermal ecosystems in particular, which span a range of temperatures within a single biogeographic area, allow us to take the laboratory into nature rather than vice versa. By isolating temperature from other drivers, its ecological effects can be quantified without any loss of realism, and transient and equilibrial responses can be measured in the same system across scales that are not feasible using other empirical methods. Embedding manipulative experiments within geothermal gradients is an especially powerful approach, informing us to what extent small-scale experiments can predict the future behaviour of real ecosystems. Geothermal areas also act as sentinel systems by tracking responses of ecological networks to warming and helping to maintain ecosystem functioning in a changing landscape by providing sources of organisms that are preadapted to different climatic conditions. Here, we highlight the emerging use of geothermal systems in climate change research, identify novel research avenues, and assess their roles for catalysing our understanding of ecological and evolutionary responses to global warming., (© 2014 John Wiley & Sons Ltd.)

Livestock grazing can be used as a key management tool for maintaining healthy ecosystems. However, the effectiveness of using grazing to modify habitat for species of conservation concern depends on how the grazing regime is implemented. Timing of grazing is one grazing regime component that is less understood than grazing intensity and grazer identity, but is predicted to have important implications for plant and higher trophic level responses. We experimentally assessed how timing of cattle grazing affected plant and arthropod communities in high-elevation grasslands of southwest Montana to better evaluate its use as a tool for multi-trophic level management. We manipulated timing of grazing, with one grazing treatment beginning in mid-June and the other in mid-July, in two experiments conducted in different grassland habitat types (i.e., wet meadow and upland) in 2011 and 2012. In the upland grassland experiment, we found that both early and late grazing treatments reduced forb biomass, whereas graminoid biomass was only reduced with late grazing. Grazing earlier in the growing season versus later did not result in greater recovery of graminoid or forb biomass as expected. In addition, the density of the most ubiquitous grassland arthropod order (Hemiptera) was reduced by both grazing treatments in upland grasslands. A comparison of end-of-season plant responses to grazing in upland versus wet meadow grasslands revealed that grazing reduced graminoid biomass in the wet meadow and forb biomass in the upland, irrespective of timing of grazing. Both grazing treatments also reduced end-of-season total arthropod and Hemiptera densities and Hemiptera biomass in both grassland habitat types. Our results indicate that both early and late season herbivory affect many plant and arthropod characteristics in a similar manner, but grazing earlier may negatively impact species of conservation concern requiring forage earlier in the growing season.

Common Sense Parenting is a parent-training program that is widely disseminated, has promising preliminary support, and is being tested in a randomized controlled trial that targets lower-income, urban 8th-grade students and their families (recruited in two annual cohorts) to improve the transition to high school. The workshop-based program is being tested in both standard 6-session (CSP) and modified 8-session (CSP Plus) formats; CSP Plus adds adolescent-skills training activities. To offer a comprehensive picture of implementation outcomes in the CSP trial, we describe the tools used to assess program adherence, quality of delivery, program dosage, and participant satisfaction, and report the implementation data collected during the trial. Results indicated that workshop leaders had high adherence to the program content and manual-stated goal times of the CSP/CSP Plus curriculum and delivered the intervention with high quality. The majority of intervention families attended some or all of the sessions. Participant satisfaction ratings for the workshops were high. There were no significant cohort differences for adherence, quality and dosage; however, there were significant cohort improvements for participant satisfaction. Positive fidelity results may be due to the availability of detailed workshop leader guides, in addition to ongoing training and supervision, which included performance-based feedback., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Background: Finding effective and efficient models to train large numbers of suicide prevention interventionists, including 'hotline' crisis counselors, is a high priority. Train-the-trainer (TTT) models are widely used but understudied., Aims: To assess the extent to which trainers following TTT delivered the Applied Suicide Intervention Skills Training (ASIST) program with fidelity, and to examine fidelity across two trainings and seven training segments., Method: We recorded and reliably rated trainer fidelity, defined as adherence to program content and competence of program delivery, for 34 newly trained ASIST trainers delivering the program to crisis center staff on two separate occasions. A total of 324 observations were coded. Trainer demographics were also collected., Results: On average, trainers delivered two-thirds of the program. Previous training was associated with lower levels of trainer adherence to the program. In all, 18% of trainers' observations were rated as solidly competent. Trainers did not improve fidelity from their first to second training. Significantly higher fidelity was found for lectures and lower fidelity was found for interactive training activities including asking about suicide and creating a safe plan., Conclusions: We found wide variability in trainer fidelity to the ASIST program following TTT and few trainers had high levels of both adherence and competence. More research is needed to examine the cost-effectiveness of TTT models.

Background: Finding effective and efficient options for training mental health professionals to assess and manage suicide risk is a high priority., Aims: To test whether an innovative, brief workshop can improve provider knowledge, confidence, and written risk assessment in a multidisciplinary sample of ambulatory and acute services professionals and trainees., Methods: We conducted a pre/post evaluation of a 3 h workshop designed to improve clinical competence in suicide risk assessment by using visual concept mapping, medical records documentation, and site-specific crisis response options. Participants (N = 338 diverse mental health professionals) completed pre- and postworkshop questionnaires measuring their knowledge and confidence. Before and after the workshop, participants completed documentation for a clinical vignette. Trained coders rated the quality of risk assessment formulation before and after training., Results: Participants' knowledge, confidence, and objectively-rated documentation skills improved significantly (p < .001), with large effect sizes. Participants' expectation of their ability to transfer workshop content to their clinical practice was high (mean = 4.10 on 1-5 scale)., Conclusions: Commitment to Living is a promising, innovative, and efficient curriculum for educating practicing clinicians to assess and respond to suicide risk. Well-designed, brief, suicide risk management programs can improve clinicians' knowledge, confidence, and skill.

Large dams have been constructed on rivers to meet human demands for water, electricity, navigation, and recreation. As a consequence, flow and temperature regimes have been altered, strongly affecting river food webs and ecosystem processes. Experimental high-flow dam releases, i.e., controlled floods, have been implemented on the Colorado River, U.S.A., in an effort to reestablish pulsed flood events, redistribute sediments, improve conditions for native fishes, and increase understanding of how dam operations affect physical and biological processes. We quantified secondary production and organic matter flows in the food web below Glen Canyon dam for two years prior and one year after an experimental controlled flood in March 2008. Invertebrate biomass and secondary production declined significantly following the flood (total biomass, 55% decline; total production, 56% decline), with most of the decline driven by reductions in two nonnative invertebrate taxa, Potamopyrgus antipodarum and Gammarus lacustris. Diatoms dominated the trophic basis of invertebrate production before and after the controlled flood, and the largest organic matter flows were from diatoms to the three most productive invertebrate taxa (P. antipodarum, G. lacustris, and Tubificida). In contrast to invertebrates, production of rainbow trout (Oncorhynchus mykiss) increased substantially (194%) following the flood, despite the large decline in total secondary production of the invertebrate assemblage. This counterintuitive result is reconciled by a post-flood increase in production and drift concentrations of select invertebrate prey (i.e., Chironomidae and Simuliidae) that supported a large proportion of trout production but had relatively low secondary production. In addition, interaction strengths, measured as species impact values, were strongest between rainbow trout and these two taxa before and after the flood, demonstrating that the dominant consumer-resource interactions were not necessarily congruent with the dominant organic matter flows. Our study illustrates the value of detailed food web analysis for elucidating pathways by which dam management may alter production and strengths of species interactions in river food webs. We suggest that controlled floods may increase production of nonnative rainbow trout, and this information can be used to help guide future dam management decisions.

Suicide is the third leading cause of death among 10-24-year-olds and the target of school-based prevention efforts. Gatekeeper training, a broadly disseminated prevention strategy, has been found to enhance participant knowledge and attitudes about intervening with distressed youth. Although the goal of training is the development of gatekeeper skills to intervene with at-risk youth, the impact on skills and use of training is less known. Brief gatekeeper training programs are largely educational and do not employ active learning strategies such as behavioral rehearsal through role play practice to assist skill development. In this study, we compare gatekeeper training as usual with training plus brief behavioral rehearsal (i.e., role play practice) on a variety of learning outcomes after training and at follow-up for 91 school staff and 56 parents in a school community. We found few differences between school staff and parent participants. Both training conditions resulted in enhanced knowledge and attitudes, and almost all participants spread gatekeeper training information to others in their network. Rigorous standardized patient and observational methods showed behavioral rehearsal with role play practice resulted in higher total gatekeeper skill scores immediately after training and at follow-up. Both conditions, however, showed decrements at follow-up. Strategies to strengthen and maintain gatekeeper skills over time are discussed.

A systematic search of popular and scholarly databases identified workshops that addressed general clinical competence in the assessment or management of suicide risk, targeted mental health professionals, and had at least one peer-reviewed publication. We surveyed workshop developers and examined empirical articles associated with each workshop. The state of workshop education is characterized by presenting the learning objectives, educational formats, instructor factors, and evaluation studies. Workshops are efficacious for transferring knowledge and shifting attitudes; however, their role in improving clinical care and outcomes of suicidal patients has yet to be determined., (© 2011 The American Association of Suicidology.)

The large gap between intervention outcomes demonstrated in efficacy trials and the apparent ineffectiveness of these same programs in community settings has prompted investigators and practitioners to look closely at implementation fidelity. Critically important, but often overlooked, are the implementers who deliver evidence-based programs -- the effectiveness of programs cannot surpass skill levels of the people implementing them. This article distinguishes fidelity at the programmatic level from implementer fidelity. Two components of implementer fidelity are defined. Implementer adherence and competence are proposed to be related but unique constructs that can be reliably measured for training¸ monitoring, and outcomes research. Observational measures from a school-based preventive intervention are provided and the unique contributions of implementer adherence and competence are illustrated. Distinguishing implementer adherence to the manual and competence in program delivery is a critical next step in child mental health program implementation research.

Increased nutrient mobilization by human activities represents one of the greatest threats to global ecosystems, but its effects on ecosystem productivity can differ depending on food web structure. When this structure facilitates efficient energy transfers to higher trophic levels, evidence from previous large-scale enrichments suggests that nutrients can stimulate the production of multiple trophic levels. Here we report results from a 5-year continuous nutrient enrichment of a forested stream that increased primary consumer production, but not predator production. Because of strong positive correlations between predator and prey production (evidence of highly efficient trophic transfers) under reference conditions, we originally predicted that nutrient enrichment would stimulate energy flow to higher trophic levels. However, enrichment decoupled this strong positive correlation and produced a nonlinear relationship between predator and prey production. By increasing the dominance of large-bodied predator-resistant prey, nutrient enrichment truncated energy flow to predators and reduced food web efficiency. This unexpected decline in food web efficiency indicates that nutrient enrichment, a ubiquitous threat to aquatic ecosystems, may have unforeseen and unpredictable effects on ecosystem structure and productivity.

Responses of detrital pathways to nutrients may differ fundamentally from pathways involving living plants: basal carbon resources can potentially decrease rather than increase with nutrient enrichment. Despite the potential for nutrients to accelerate heterotrophic processes and fluxes of detritus, few studies have examined detritus-nutrient dynamics at whole-ecosystem scales. We quantified organic matter (OM) budgets over three consecutive years in two detritus-based Appalachian (U.S.A.) streams. After the first year, we began enriching one stream with low-level nitrogen and phosphorus inputs. Subsequent effects of nutrients on outputs of different OM compartments were determined using randomized intervention analysis. Nutrient addition did not affect dissolved or coarse particulate OM export but had dramatic effects on fine particulate OM (FPOM) export at all discharges relative to the reference stream. After two years of enrichment, FPOM export was 340% higher in the treatment stream but had decreased by 36% in the reference stream relative to pretreatment export. Ecosystem respiration, the dominant carbon output in these systems, also increased in the treatment stream relative to the reference, but these changes were smaller in magnitude than those in FPOM export. Nutrient enrichment accelerated rates of OM processing, transformation, and export, potentially altering food-web dynamics and ecosystem stability in the long term. The results of our large-scale manipulation of a detrital ecosystem parallel those from analogous studies of soils, in which net loss of organic carbon has often been shown to result from experimental nutrient addition at the plot scale. Streams are useful model systems in which to test the effects of nutrients on ecosystem-scale detrital dynamics because they allow both the tracking of OM conversion along longitudinal continua and the integrated measurement of fluxes of transformed material through downstream sites.

Most aquatic and terrestrial ecosystems are experiencing increased nutrient availability, which is affecting their structure and function. By altering community composition and productivity of consumers, enrichment can indirectly cause changes in the pathways and magnitude of material flows in food webs. These changes, in turn, have major consequences for material storage and cycling in the ecosystem. Understanding mechanisms and predicting consequences of nutrient-induced changes in material flows requires a quantitative food web approach that combines information on consumer energetics and consumer-resource stoichiometry. We examined effects of a whole-system experimental nutrient enrichment on the trophic basis of production and the magnitude and pathways of carbon (C), nitrogen (N), and phosphorus (P) flows in a detritus-based stream food web. We compared the response of the treated stream to an adjacent reference stream throughout the study. Dietary composition and elemental flows varied considerably among invertebrate functional feeding groups. During nutrient enrichment, increased flows of leaf litter and amorphous detritus to shredders and gatherers accounted for most of the altered flows of C from basal resources to consumers. Nutrient enrichment had little effect on patterns of material flows but had large positive effects on the magnitude of C, N, and P flows to consumers (mean increase of 97% for all elements). Nutrient-specific food webs revealed similar flows of N and P to multiple functional groups despite an order of magnitude difference among groups in consumption of C. Secondary production was more strongly related to consumption of nutrients than C, and increased material flows were positively related to the degree of consumer-resource C:P and C:N imbalances. Nutrient enrichment resulted in an increased proportion of detrital C inputs consumed by primary consumers (from -15% to 35%) and a decreased proportion of invertebrate prey consumed by predators (from -80% to 55%). Our results demonstrate that nutrient enrichment of detritus-based systems may reduce stoichiometric constraints on material flows, increase the contribution of consumers to C, N, and P cycling, alter the proportion of C inputs metabolized by consumers, and potentially lead to reduced ecosystem-level storage of C.

Most nutrient enrichment studies in aquatic systems have focused on autotrophic food webs in systems where primary producers dominate the resource base. We tested the heterotrophic response to long-term nutrient enrichment in a forested, headwater stream. Our study design consisted of 2 years of pretreatment data in a reference and treatment stream and 2 years of continuous nitrogen (N) + phosphorus addition to the treatment stream. Studies were conducted with two leaf species that differed in initial C:N, Rhododendron maximum (rhododendron) and Acer rubrum (red maple). We determined the effects of nutrient addition on detrital resources (leaf breakdown rates, litter C:N and microbial activity) and tested whether nutrient enrichment affected macroinvertebrate consumers via increased biomass. Leaf breakdown rates were ca. 1.5 and 3x faster during the first and second years of enrichment, respectively, in the treatment stream for both leaf types. Microbial respiration rates of both leaf types were 3x higher with enrichment, and macroinvertebrate biomass associated with leaves increased ca. 2-3x with enrichment. The mass of N in macroinvertebrate biomass relative to leaves tended to increase with enrichment up to 6x for red maple and up to 44x for rhododendron leaves. Lower quality (higher C:N) rhododendron leaves exhibited greater changes in leaf nutrient content and macroinvertebrate response to nutrient enrichment than red maple leaves, suggesting a unique response by different leaf species to nutrient enrichment. Nutrient concentrations used in this study were moderate and equivalent to those in streams draining watersheds with altered land use. Thus, our results suggest that similarly moderate levels of enrichment may affect detrital resource quality and subsequently lead to altered energy and nutrient flow in detrital food webs.