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Capture and manipulation are an integral part of wildlife research and management. These practices, however, can affect animals either directly or indirectly, and studies should generally evaluate the consequences of captures to ensure animal welfare and reduce sampling bias. Here, we investigated the indirect, behavioural effects of live‐capture on escape response to humans in Alpine marmot Marmota marmota within the Stelvio National Park (central Italian Alps) over three seasons (2021–2023). We used flight initiation distance (FID) as a measure of escape response and tested it in relation to capture status using linear mixed modelling. Captures did not have any detectable effect on escape response, and FID was best explained by covariates such as starting distance, distance to nearest burrow, current behaviour during the observation and year of observation. It might be that, in marmots, escape response to humans is a rather inert behaviour. As such, although we cannot rule out unmeasured effects, capture may not represent an excessively traumatic experience which could trigger immediate behavioural modification. In turn, capture is unlikely to compromise animal welfare or cause scientific bias in studies investigating escape response in this species, at least over the short term. [ABSTRACT FROM AUTHOR]

Why does a beneficial treatment effect on a longitudinal biomarker not translate into overall treatment benefit on survival, when the biomarker is in fact a prognostic factor of survival? In a recent exploratory data analysis in oncology, we were faced with this seemingly paradoxical result. To address this problem, we applied a theoretically principled methodology called dynamic path analysis, which allows us to perform mediation analysis with a longitudinal mediator and survival outcome. The aim of the analysis is to decompose the total treatment effect into a direct treatment effect and an indirect treatment effect mediated through a carefully constructed mediation path. The dynamic nature of the underlying methodology enables us to describe how these effects evolve over time, which can add to the mechanistic understanding of the underlying processes. In this paper, we present a detailed description of the dynamic path analysis framework and illustrate its application to survival mediation analysis using simulated and real data. The use case analysis provides clarity on the specific exploratory question of interest while the methodology generalizes to a wide range of applications in drug development where time‐to‐event is the primary clinical outcome of interest. [ABSTRACT FROM AUTHOR]

Temperature and resource availability are pivotal factors influencing phytoplankton community structures. Numerous prior studies demonstrated their significant influence on phytoplankton stoichiometry, cell size, and growth rates. The growth rate, serving as a reflection of an organism's success within its environment, is linked to stoichiometry and cell size. Consequently, alterations in abiotic conditions affecting cell size or stoichiometry also exert indirect effects on growth. However, such results have their limitations, as most studies used a limited number of factors and factor levels which gives us limited insights into how phytoplankton respond to environmental conditions, directly and indirectly. Here, we tested for the generality of patterns found in other studies, using a combined multiple‐factor gradient design and two single species with different size characteristics. We used a structural equation model (SEM) that allowed us to investigate the direct cumulative effects of temperature and resource availability (i.e., light, N and P) on phytoplankton growth, as well as their indirect effects on growth through changes in cell size and cell stoichiometry. Our results mostly support the results reported in previous research thus some effects can be identified as dominant effects. We identified rising temperature as the dominant driver for cell size reduction and increase in growth, and nutrient availability (i.e., N and P) as dominant factor for changes in cellular stoichiometry. However, indirect effects of temperature and resources (i.e., light and nutrients) on species' growth rates through cell size and cell stoichiometry differed across the two species suggesting different strategies to acclimate to its environment. [ABSTRACT FROM AUTHOR]

Learning English as a second language (ESL) has garnered significant attention from researchers and practitioners over the past few decades, with numerous ESL learning outcomes examined in the literature. However, self-sustained learning (SSL), a crucial factor in promoting students' sustained learning and development within a sustainable society, has long been overlooked. To deepen the understanding of SSL, especially in the context of ESL in China, this study examined the direct and indirect effects of intercultural communicative skills, language mindset, and positive L2 self on sustained English learning among 1238 Chinese college students through descriptive statistics and a Structural Equation Modeling (SEM) mediation analysis. The results indicated that Chinese college students exhibited a strong language mindset and positive L2 self. They also scored high in intercultural communicative skills and long-term self-sustained English learning. SEM analysis showed that, after controlling for students' demographic characteristics, both intercultural communicative skills and language mindset positively predicted positive L2 self and self-sustained English learning. Moreover, intercultural communicative skills and language mindset had significant and positive indirect effects on self-sustained English learning through positive L2 self, underscoring the significant mediating role of positive L2 self in the relationships between intercultural communicative skills, language mindset, and self-sustained English learning. These findings suggest that, to promote self-sustained learning among English learners, instructors should enhance students' intercultural communicative skills, foster a growth language mindset, and cultivate positive language learning beliefs. [ABSTRACT FROM AUTHOR]

Mediation analysis is increasingly used in the social sciences. Extension to social network data, however, has proved difficult because statistical network models are formulated at a lower level of analysis (the dyad) than many outcomes of interest. This study introduces a general approach for micro-macro mediation analysis in social networks. The author defines the average mediated micro effect (AMME) as the indirect effect of a network selection process on an individual, group, or organizational outcome through its effect on an intervening network variable. The author shows that the AMME can be nonparametrically identified using a wide range of common statistical network and regression modeling strategies under the assumption of conditional independence among multiple mediators. Nonparametric and parametric algorithms are introduced to generically estimate the AMME in a multitude of research designs. The author illustrates the utility of the method with an applied example using cross-sectional National Longitudinal Study of Adolescent to Adult Health data to examine the friendship selection mechanisms that indirectly shape adolescent school performance through their effect on network structure. [ABSTRACT FROM AUTHOR]

Climate change stressors are progressively simplifying biogenic habitats in the terrestrial and marine realms, and consequently altering the structure of associated species communities.Here, we used a volcanic CO2 seep in Papua New Guinea to test in situ if altered reef architecture due to ocean acidification reshuffles associated fish assemblages.We observed replacement of branching corals by massive corals at the seep, with simplified coral architectural complexity driving abundance declines between 60% and 86% for an assemblage of damselfishes associated with branching corals. An experimental test of habitat preference for a focal species indicated that acidification does not directly affect habitat selection behaviour, with changes in habitat structural complexity consequently appearing to be the stronger driver of assemblage reshuffling. Habitat health affected anti‐predator behaviour, with P. moluccensis becoming less bold on dead branching corals relative to live branching corals, irrespective of ocean acidification.We conclude that coral reef fish assemblages are likely to be more sensitive to changes in habitat structure induced by increasing pCO2 than any direct effects on behaviour, indicating that changes in coral architecture and live cover may act as important mediators of reef fish community structures in a future ocean. [ABSTRACT FROM AUTHOR]

During 2005–2007, the Securities and Exchange Commission conducted a randomized trial in which it removed short-sale restrictions from one third of the Russell 3000 firms. Early studies found modest market microstructure effects of removing the restrictions but no effect on short interest, stock returns, volatility, or price efficiency. More recently, many studies have attributed a wide range of indirect outcomes to this experiment, mostly without assessing the causal channels for those outcomes. We examine the three most often cited causal channels for these indirect effects: short interest, returns, and managerial fear. We find no evidence to support these channels. We then reexamine the principal findings in four recent studies using a sample that closely matches the actual experiment and a common research design and find minimal support for the reported indirect effects. Our findings highlight the importance of confirming a causal channel or an economic mechanism and show that sample selection and specification choices can produce statistical significance even without an underlying economic mechanism. This paper was accepted by David Sraer, finance. Supplemental Material: The internet appendix and data are available at https://doi.org/10.1287/mnsc.2023.4918. [ABSTRACT FROM AUTHOR]

Rapid advancements in artificial intelligence (AI) are driving transformative changes in many areas, with significant environmental implications. Yet, environmental assessments for specific applications are scarce. This study presents an in‐depth life cycle assessment of “Foodforecast,” a machine learning (ML) cloud service designed to reduce food waste in bakeries by optimizing sales forecasting. It covers four impact categories: global warming, abiotic resource depletion, cumulative energy demand, and freshwater eutrophication. The assessment includes both the direct environmental impacts of the ML model and the underlying system hardware, as well as the indirect benefits of avoided bakery returns compared to traditional ordering methods, using real‐world case study data. In 2022, “Foodforecast” led to an average 30% reduction in bakery returns, primarily bread and rolls, according to sales reports. The associated environmental benefits significantly outweighed the system's direct impacts by one to three orders of magnitude across impact categories and return utilization scenarios. The study identifies support activities such as service maintenance during deployment as major direct impact factors, surpassing those from cloud compute for ML operations. Data processing and inference dominate the latter, while the much‐discussed ML training plays a minor role. The environmental consequences of AI are complex and dual sided. This case study demonstrates that AI might provide environmental benefits in certain contexts, yet results are constrained by methodological challenges and data uncertainties. There remains a need for further holistic LCAs across different ML applications to inform decision‐making processes and ultimately guide the responsible use of AI. [ABSTRACT FROM AUTHOR]

Traditional linear mediation analysis has inherent limitations when it comes to handling high-dimensional mediators. Particularly, accurately estimating and rigorously inferring mediation effects is challenging, primarily due to the intertwined nature of the mediator selection issue. Despite recent developments, the existing methods are inadequate for addressing the complex relationships introduced by confounders. To tackle these challenges, we propose a novel approach called DP2LM (Deep neural network-based Penalized Partially Linear Mediation). This approach incorporates deep neural network techniques to account for nonlinear effects in confounders and utilizes the penalized partially linear model to accommodate high dimensionality. Unlike most existing works that concentrate on mediator selection, our method prioritizes estimation and inference on mediation effects. Specifically, we develop test procedures for testing the direct and indirect mediation effects. Theoretical analysis shows that the tests maintain the Type-I error rate. In simulation studies, DP2LM demonstrates its superior performance as a modeling tool for complex data, outperforming existing approaches in a wide range of settings and providing reliable estimation and inference in scenarios involving a considerable number of mediators. Further, we apply DP2LM to investigate the mediation effect of DNA methylation on cortisol stress reactivity in individuals who experienced childhood trauma, uncovering new insights through a comprehensive analysis. [ABSTRACT FROM AUTHOR]

Purpose: Since teaching practice is the most important within-school determinant of student learning outcomes, a deepened understanding of how and why school leadership contributes to effective teaching is needed. This article aimed to systematically review the knowledge that has been accumulated about the indirect relations between school leadership and instructional practices. Design/methodology/approach: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guided the selection of relevant articles from the databases Scopus and Google Scholar. Twenty-six published works met the eligibility criteria and were included in the narrative synthesis and content analysis. Findings: The most frequently measured mediators of the effects of school leadership on teaching practice were teacher collaboration, professional learning and teacher self-efficacy. Most studies simultaneously modeled multiple mediated pathways from school leadership to teaching practice. However, only a few analyzed studies used time lags when examining relationships between constructs. Originality/value: This is the first study to systematically review knowledge on pathways through which school leadership is related to classroom instruction. Thus, this review provides a comprehensive understanding of processes through which school leadership achieves its effects on instructional practices. [ABSTRACT FROM AUTHOR]

Access to higher education depends on the interaction between social origins and academic performance: background resources boost academic skills; but even when controlling for performance, privileged students are more likely to make ambitious choices and further transitions. Recent literature has shown that inequality in educational choices is heterogeneous across countries. However, it is still not well understood how different institutional designs within countries may affect the workings of those effects and how they can strengthen or weaken the inequality of educational opportunities. Using high-quality register data from the Brazilian higher education system, our work contributes to this understanding by investigating how SES and performance interact and drive students' choice between three different tracks: not entering higher education, entering the private system, or entering the public system. We developed a strategy to encompass multinomial choices and decompose the inequalities into primary and secondary effects. Using the Shapley Value decomposition strategy, we correct an intrinsic asymmetry that biased previous results. Our findings suggest affluent students enjoy dual advantages: high exam performance amplifies access to public universities (indirect effect) and family resources offset subpar performance, ensuring private university access (direct effect). We found no signs of multiplicative advantages.

Government owned transport companies in Ghana ought to up their management decisions on the factors surrounding the Supportive Work Culture of their staffs especially, the drivers. Without drivers there will be no movement of buses to various destinations. Besides, it is the drivers that come into contact with customers or passengers every day and faces a lot of safety issues and other road challenges such as traffic and bad roads and bad road networks. Hence, since drivers have been agitating and demonstrating for better conditions of service, calls for further investigation into the sector, it means job satisfaction has been a problem for them. Since the outer loadings and outer weights affects many of the constructs. This research model tested showed that employees work behaviour and commitment have influence on their Job Satisfaction at work. This also reveals that the Good Governance aspect needs much improvement to reflect the desire of the drivers in order to achieve the company objectives. The Outer loadings of the constructs for the various variables showed both weak and higher Outer Loadings but a combination of all these was significant in almost all the measurements results.

Indirect interactions among species within ecological communities govern ecological and evolutionary processes as much as, or even more, than direct effects. In insect‐pollinated plant communities, indirect interactions between plants can be mediated by shared pollinators, and may influence plant fitness, population growth and community structure. As individuals are the entities actually interacting in nature, rather than species, downscaling a hierarchical level (i.e. from species to individuals) is essential to understand the underlying processes promoting these indirect interactions. We combined empirical data on plant–pollinator interactions collected in Mediterranean shrublands with a novel modelling framework to assess how the patterns of heterospecific and conspecific pollinator sharing between plant individuals are generated and their fitness implications. We found that the effects of flowering synchrony on pollinator sharing among conspecific and heterospecific plant individuals outperformed those of spatial distance. Our results revealed that plant individuals that shared more pollinators with conspecifics were also involved in a higher pollinator sharing with heterospecifics. For most plant species, the sharing of pollinator species between heterospecific plant individuals produced positive mean fitness outcomes, as long as plants did not share many pollinator interactions, which had negative effects on their fitness. At the level of plant individuals, we found that specific combinations of conspecific and heterospecific pollinator sharing lead to distinct reproductive outcomes that placed each individual along a competition–facilitation continuum. Interestingly, most plant species included a higher proportion of individuals likely experiencing competition compared to those potentially involved in facilitation processes. Our contribution provides novel insights into the factors responsible for local‐scale indirect interactions within communities and their individual‐level functional consequences. Such intricate patterns of indirect interactions have far‐reaching implications, as the transitions of plant individuals along competitive or facilitative processes mediated by shared mutualists may contribute significantly to the functioning and coexistence of ecological communities. [ABSTRACT FROM AUTHOR]

Network science has revealed that the architecture of many complex biological, physical, and social systems facilitates the direct and indirect propagation of disturbances. Ecological disturbances, such as species extinctions and the disruption of their interactions by environmental change drivers, may propagate across space and time. However, the scale over which these impacts propagate remains largely unknown. Ecological disturbances vary in their propagation pathways and effects on network structure and functioning. The characteristics of species and of their interaction networks and metanetworks contribute to predicting the rate and extent to which different disturbances spread across ecological communities. The identification of spatial or temporal boundaries for ecological networks is key to capturing metanetwork dynamics and the scale over which disturbance effects can propagate. Despite the development of network science, we lack clear heuristics for how far different disturbance types propagate within and across species interaction networks. We discuss the mechanisms of disturbance propagation in ecological networks, and propose that disturbances can be categorized into structural, functional, and transmission types according to their spread and effect on network structure and functioning. We describe the properties of species and their interaction networks and metanetworks that determine the indirect, spatial, and temporal extent of propagation. We argue that the sampling scale of ecological studies may have impeded predictions regarding the rate and extent that a disturbance spreads, and discuss directions to help ecologists to move towards a predictive understanding of the propagation of impacts across interacting communities and ecosystems. [ABSTRACT FROM AUTHOR]

To be effective in the prevention of adolescent problem gambling, it is fundamental to enhance knowledge about the antecedents of gambling problem severity and the mechanisms through which these dimensions are related to problematic gambling behavior. This study aimed at testing how selected cognitive (correct knowledge of gambling and gambling-related cognitive distortions) and affective (positive economic perception of gambling and expectation and enjoyment and arousal towards gambling) variables are related to gambling frequency and gambling problem severity. Problem gambling was conceptualized as Gambling Disorder symptoms according to the last edition of the DSM. Participants were 447 Italian high school students (68% males, mean age = 16.8, SD = 0.84). Structural Equation Models (SEMs) conducted with adolescent gamblers attested two indirect effects from knowledge to problem gambling: One through gambling-related cognitive distortions and one through gambling frequency. Overall, results confirmed that adolescent problem gambling is a complex phenomenon explained by multiple and different factors. Practical implications for preventive efforts are discussed. [ABSTRACT FROM AUTHOR]

Decision-makers want to be reliably advised on the implications of the decisions they make. Very sophisticated models, which decision-makers are often unfamiliar with, are typically used to provide such assessments for large and complex systems. However, even having access to these models, decision-makers can rarely handle them. A model is best known to its developers, who, therefore, need to be contracted to estimate the effects of the proposed policies. This takes time and money, yet leaves the credibility of the results questionable in countries with a limited culture of cooperation between decision-makers and a modeling community. One possible, yet partial, solution is to use an ensemble of models. Another option is to use a set of compact meta-models to address specific policies and measures; the parameters of such compact models can be assessed using other, large and complex, models. Decision-makers can run these simple compact models on their own to make policy dialogue more operational and to have more confidence in the results. This paper presents one such model, which consists of 95 compact sub-models designed to outline comprehensive energy efficiency programs, along with the results of its pilot application for an illustrative set of policies. This application has shown, that such models may serve as an effective tool for a prompt policy dialogue with all stakeholders in compiling the policy package to untap the most of the available energy efficiency potential to meet sector-specific or economy-wide goals in terms of energy savings or energy intensity reduction. [ABSTRACT FROM AUTHOR]

Background: This study takes on the challenge of quantifying a complex causal loop diagram describing how poverty and health affect each other, and does so using longitudinal data from The Netherlands. Furthermore, this paper elaborates on its methodological approach in order to facilitate replication and methodological advancement. Methods: After adapting a causal loop diagram that was built by stakeholders, a longitudinal structural equation modelling approach was used. A cross-lagged panel model with nine endogenous variables, of which two latent variables, and three time-invariant exogenous variables was constructed. With this model, directional effects are estimated in a Granger-causal manner, using data from 2015 to 2019. Both the direct effects (with a one-year lag) and total effects over multiple (up to eight) years were calculated. Five sensitivity analyses were conducted. Two of these focus on lower-income and lower-wealth individuals. The other three each added one exogenous variable: work status, level of education, and home ownership. Results: The effects of income and financial wealth on health are present, but are relatively weak for the overall population. Sensitivity analyses show that these effects are stronger for those with lower incomes or wealth. Physical capability does seem to have strong positive effects on both income and financial wealth. There are a number of other results as well, as the estimated models are extensive. Many of the estimated effects only become substantial after several years. Conclusions: Income and financial wealth appear to have limited effects on the health of the overall population of The Netherlands. However, there are indications that these effects may be stronger for individuals who are closer to the poverty threshold. Since the estimated effects of physical capability on income and financial wealth are more substantial, a broad recommendation would be that including physical capability in efforts that are aimed at improving income and financial wealth could be useful and effective. The methodological approach described in this paper could also be applied to other research settings or topics. [ABSTRACT FROM AUTHOR]

Internalizing symptoms have been linked to bullying perpetration and victimization in adolescence. However, the directions of any causal relationships remain unclear, and limited research has identified the mechanisms that explain the associations. Given the salience of peer relationships during the teenage years, we examine whether perceived support from friends is one such mechanism. By using a transactional framework and four waves of longitudinal panel data on over 900 youth, we test both cross-lagged and indirect associations between bullying perpetration, bullying victimization, internalizing symptoms, and perceived friend support. Our method represents one of the most rigorous tests to date of the mutual influences among these factors. The results show that internalizing symptoms and perceived friend support were reciprocally linked to bullying victimization, but perceived support did not predict internalizing symptoms, and bullying perpetration neither preceded nor followed perceived support or internalizing symptoms. There were no significant indirect paths between bullying involvement and internalizing symptoms through perceived friend support. The results provide only partial support for a transactional model in which bullying victimization, support, and internalizing symptoms are reciprocally related. The implications of these findings for theory, future research, and practice are discussed. [ABSTRACT FROM AUTHOR]

Pathogens are ubiquitous in ecosystems and play a key role in affecting host community structure. In grasslands, large grazing animals such as cattle and sheep have been shown to affect foliar fungal pathogens. However, theory and empirical studies have come to conflicting conclusions because grazers can directly and indirectly impact pathogens through a wide variety of mechanisms and various grazers may impact pathogens in different ways. A better understanding of the mechanisms by which grazers impact pathogens is important for a fundamental understanding of herbivore pathogen interactions and also to optimise grazing managements to reduce pathogen outbreaks.Here, we investigate multiple mechanisms by which livestock grazing impacts foliar fungal pathogens in grasslands. We integrate a large‐scale grazing experiment, with a removal experiment manipulating plant density and litter biomass, to identify direct and indirect effects of two herbivores on pathogens with different life histories (biotrophs and necrotrophs), in a temperate grassland in northeast China.We found that grazing by cattle and sheep had contrasting impacts: cattle grazing significantly reduced pathogen load, of both biotrophs and necrotrophs, whereas sheep grazing increased biotrophic pathogen load, but did not affect the necrotrophs. The grazing effects were mostly indirect and mediated by different impacts of the herbivores on plant community structure. Cattle grazing reduced pathogen load because it reduced the abundance of susceptible, fast‐growing plants, and the overall density of plants, while sheep grazing increased pathogen infection because it reduced the abundance of resistant plant species. Plant diversity also reduced pathogen infection but these effects were independent of the herbivores.Our results show that different herbivores can have contrasting impacts on pathogen infection through contrasting impacts on host community competence. This suggests the importance of considering multiple mechanisms simultaneously to evaluate the impact of herbivores on host‐pathogen interactions. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Introduction: This exploratory study delves into the relationships between noncognitive skills and academic achievement within the unique context of STEM schools in Kazakhstan. Methods: Survey data were collected from 109 teachers and 395 students at a STEM secondary school in Kazakhstan. Correlational, regression and path analyses were conducted to explore the relationship between non-cognitive skills and academic performance in Mathematics, Computer Science, Physics, and Chemistry classes. Results: The results showed that out of the 26 skills, eight had a direct impact, 12 had an indirect impact, and six had no impact on academic achievement of students in the four STEM subjects. Discussion: This study is the first to explicitly examine the impact of one group of non-cognitive skills on academic achievement of students in STEM subjects mediated by another group of these skills. Teachers are encouraged to integrate non-cognitive skill development into curricula, tailored to subject-specific needs. Policymakers can use findings to inform equitable skill development policies. [ABSTRACT FROM AUTHOR]

Livestock overgrazing causes environmental degradation, species invasion, biodiversity loss, and productivity decline, with profound consequences for ecological sustainability and human livelihoods. Habitat protection can mitigate such impacts, but we know little about how the long‐term recovery of plant communities from livestock overgrazing depends on the presence of encroaching shrubs. Here, we explored how shrub encroachment mediates the effects of habitat protection (i.e., livestock exclusion and creation of UNESCO protected areas) on biodiversity recovery and ecosystem functioning (i.e., biomass productivity). We leveraged a long‐term (15–25 years) experiment of livestock exclusion and complemented it with the removal of an encroaching shrub species in pasture areas and protected areas. We reveal that habitat protection has positive effects on patterns of recovery. Yet, the effects of habitat protection are mediated by shrub encroachment. Encroaching shrubs have net positive effects on plant diversity in pasture areas but inhibit biodiversity recovery in protected areas. The combination of habitat protection and the removal of encroaching shrubs best enhances the recovery of plant diversity and biomass productivity. A potential underlying mechanism is the shift in plant interactions from facilitation for recruitment and associated resistance to competition for water. Understanding species interactions is key to guiding conservation and restoration actions which can turn degraded ecosystems back into functional, species‐rich communities. [ABSTRACT FROM AUTHOR]

Agricultural intensification at field and landscape scales, including increased use of agrochemicals and loss of semi‐natural habitats, is a major driver of insect declines and other community changes. Efforts to understand and mitigate these effects have traditionally focused on ecological responses. At the same time, adaptations to pesticide use and habitat fragmentation in both insects and flowering plants show the potential for rapid evolution. Yet we lack an understanding of how such evolutionary responses may propagate within and between trophic levels with ensuing consequences for conservation of species and ecological functions in agroecosystems. Here, we review the literature on the consequences of agricultural intensification on plant and animal evolutionary responses and interactions. We present a novel conceptualization of evolutionary change induced by agricultural intensification at field and landscape scales and emphasize direct and indirect effects of rapid evolution on ecosystem services. We exemplify by focusing on economically and ecologically important interactions between plants and pollinators. We showcase available eco‐evolutionary theory and plant–pollinator modelling that can improve predictions of how agricultural intensification affects interaction networks, and highlight available genetic and trait‐focused methodological approaches. Specifically, we focus on how spatial genetic structure affects the probability of propagated responses, and how the structure of interaction networks modulates effects of evolutionary change in individual species. Thereby, we highlight how combined trait‐based eco‐evolutionary modelling, functionally explicit quantitative genetics, and genomic analyses may shed light on conditions where evolutionary responses impact important ecosystem services. [ABSTRACT FROM AUTHOR]

Abstract Temperature and resource availability are pivotal factors influencing phytoplankton community structures. Numerous prior studies demonstrated their significant influence on phytoplankton stoichiometry, cell size, and growth rates. The growth rate, serving as a reflection of an organism's success within its environment, is linked to stoichiometry and cell size. Consequently, alterations in abiotic conditions affecting cell size or stoichiometry also exert indirect effects on growth. However, such results have their limitations, as most studies used a limited number of factors and factor levels which gives us limited insights into how phytoplankton respond to environmental conditions, directly and indirectly. Here, we tested for the generality of patterns found in other studies, using a combined multiple‐factor gradient design and two single species with different size characteristics. We used a structural equation model (SEM) that allowed us to investigate the direct cumulative effects of temperature and resource availability (i.e., light, N and P) on phytoplankton growth, as well as their indirect effects on growth through changes in cell size and cell stoichiometry. Our results mostly support the results reported in previous research thus some effects can be identified as dominant effects. We identified rising temperature as the dominant driver for cell size reduction and increase in growth, and nutrient availability (i.e., N and P) as dominant factor for changes in cellular stoichiometry. However, indirect effects of temperature and resources (i.e., light and nutrients) on species' growth rates through cell size and cell stoichiometry differed across the two species suggesting different strategies to acclimate to its environment.

Feedbacks are the basic linkages of living systems. In organisms, they regulate the processes of growth and homeostasis, as well as their interactions with their world. Feedback, which Judson (1980) called ‘one of the chief themes of scientific understanding,' is equally important in ecological systems. The ecological literature is rich in papers dealing with the role of feedback in various phenomena. However, we know of no comprehensive synthesis of feedbacks in ecology. Pichon et al. (2024) accomplish this, and for the first time show that ecological feedbacks can be categorized in terms of a small number of fundamental attributes. The paper brings the array of different types of feedbacks into a manageable order, providing not only the relevant theoretical framework but also guidance on methods for applying understanding to practical issues. [ABSTRACT FROM AUTHOR]

The role of facilitation in shaping natural communities has primarily been studied in the context of plant assemblages, while its relevance for mobile animals remains less understood. Our study investigates whether reciprocal interspecific facilitation may exist between fire ants (Solenopsis richteri) and cavies (Cavia aperea), two mobile animals, in the SW Atlantic coast brackish marshes. Field samples showed a spatial association between ant mounds and cavies, and that ants prefer to use cavy runways for movement within the marsh. Through experiments involving transplanting the dominant plant, cordgrass (Spartina densiflora), and manipulating cavy presence in areas with and without ant mounds, we observed that cavies forage extensively (and defecate more) near ant mounds. The ants actively remove cavy droppings in their mound vicinity. These ant activities and interactions with cavy droppings led to reduced moisture and organic content while increasing nitrate and phosphate levels in marsh sediment. Consequently, this enhanced plant growth, indirectly facilitating the cavies, which preferred consuming vegetation near ant mounds. These cascading indirect effects persisted over time; even four months after cavies left the marshes, transplanted plants near ant mounds remained larger and exhibited more leaf senescence when exposed to cavy herbivory. Therefore, the networks of positive interactions appear to generate simultaneous selection among species (populations), promoting coexistence within the community. Although complex, these reciprocal facilitative effects among mobile animals may be more common than currently believed and should be further studied to gain a better understanding of the underlying mechanisms driving species coexistence in natural communities. [ABSTRACT FROM AUTHOR]

Understory assemblages associated with canopy‐forming species such as trees, kelps, and rockweeds should respond strongly to climate stressors due to strong canopy‐understory interactions. Climate change can directly and indirectly modify these assemblages, particularly during more stressful seasons and climate scenarios. However, fully understanding the seasonal impacts of different climate conditions on canopy‐reliant assemblages is difficult due to a continued emphasis on studying single‐species responses to a single future climate scenario during a single season. To examine these emergent effects, we used mesocosm experiments to expose seaweed assemblages associated with the canopy‐forming golden rockweed, Silvetia compressa, to elevated temperature and pCO2 conditions reflecting two projected greenhouse emission scenarios (RCP 2.6 [low] & RCP 4.5 [moderate]). Assemblages were grown in the presence and absence of Silvetia, and in two seasons. Relative to ambient conditions, predicted climate scenarios generally suppressed Silvetia biomass and photosynthetic efficiency. However, these effects varied seasonally—both future scenarios reduced Silvetia biomass in summer, but only the moderate scenario did so in winter. These reductions shifted the assemblage, with more extreme shifts occurring in summer. Contrarily, future scenarios did not shift assemblages within Silvetia Absent treatments, suggesting that climate primarily affected assemblages indirectly through changes in Silvetia. Mesocosm experiments were coupled with a field Silvetia removal experiment to simulate the effects of climate‐mediated Silvetia loss on natural assemblages. Consistent with the mesocosm experiment, Silvetia loss resulted in season‐specific assemblage shifts, with weaker effects observed in winter. Together, our study supports the hypotheses that climate‐mediated changes to canopy‐forming species can indirectly affect the associated assemblage, and that these effects vary seasonally. Such seasonality is important to consider as it may provide periods of recovery when conditions are less stressful, especially if we can reduce the severity of future climate scenarios. [ABSTRACT FROM AUTHOR]

Indirect ecological effects—in which interactions of two species are modified by another species or abiotic factor—are generally considered equal to or greater in magnitude than direct effects. The ecological literature describing indirect effects suffers from redundancy and confusion regarding terminology and quantification, limiting its utility to regulators working to estimate indirect relative to direct effects in assessing environmental risks of development. To evaluate consideration for indirect ecological effects in regulatory practice, we reviewed 24 National Environmental Policy Act (NEPA) documents for proposed US mining projects to compare the treatment of indirect effects in the regulatory versus ecological literature. A clear dichotomy between regulatory and academic definitions of indirect effects suggests that NEPA documents overlook scientifically defined ecological impacts of development. Consequently, for scientific inquiry to be useful to regulators and for regulation of development to comprehensively assess risks, multidisciplinary efforts are urgently needed to bridge the gap between ecological science and environmental management. [ABSTRACT FROM AUTHOR]

The present study illustrates the outcomes of a simultaneous equation modelling that investigates the relationship between competitiveness and corruption both directly and indirectly, considering the interlinkages with the broader social structure in a sample of 110 world countries. The empirical results justify a separate analysis of the sample according with the level of human development, and outline the importance of existing income inequalities in addition to economic and social development. In high human development countries, the net effect of competitiveness on corruption is greater than its direct effect due to the indirect (positive) correlation of competitiveness with income inequality. On the contrary, in low human development countries, the final effect of competitiveness on corruption is lower than its direct effects and, therefore, the ensuing improvement on the level of corruption is reduced substantially. This finding may be ascribed to the indirect negative effect stemming from income inequalities, which exacerbate social turbulence and collisions whereas they impinge on social cohesion and institutional resilience. These issues, which are particularly intense under low social development conditions, reduce the direct, non-linear effect of competitiveness on corruption, suggesting the importance of indirect effects. [ABSTRACT FROM AUTHOR]

In the current work, we develop and analyse a prey–predator model as a semi-Kolmogorov population model in which the predator has an indirect effect on the prey. The functional response of the model is investigated as Holling type (II). We construct a stochastic environment because of the parameter's random essence to study the influence of environmental fluctuations on this model and introduce a stochastic version of the prey–predator model. Then we present a dynamical analysis of solutions, including existence, uniqueness, positivity, stochastic boundedness, and stochastic extinction of all prey. Finally, some numerical simulations are carried out to validate our theoretical findings and confirm the efficiency and adaptation of our stochastic model. [ABSTRACT FROM AUTHOR]

This research investigated the relationships of the Dark Triad traits, humor styles, and schadenfreude with 169 participants who completed the Short Dark Triad, the Humor Style Questionnaire, and a measure of schadenfreude. Significant correlations imply that those with salient dark traits (psychopathy, Machiavellianism, narcissism) elicit pleasure from others' misfortune. Additionally, schadenfreude can be a product of self‐defeating and aggressive humor styles. Indirect effect analysis revealed the significance of the indirect effect of the measured aggressive humor style on the Dark Triad's direct effects on schadenfreude. These results imply that those with salient Dark Triad traits enjoy others' misery as a means to undermine them. Hence, individuals with salient Dark Triad traits tend to engage in downward social comparison. [ABSTRACT FROM AUTHOR]

Purpose: The COVID-19 pandemic has brought significant distress on not only the physical health but also mental health of individuals. The present study investigated the direct and indirect effects from COVID-19 distress to suicidality via psychosocial and financial well-being among young people. Methods: This cross-sectional survey recruited 1472 Hong Kong young people via random sampling in 2021. The respondents completed a phone survey on COVID-19 distress, the four-item Patient Health Questionnaire and items on social well-being, financial well-being, and suicidality. Structural equation modeling (SEM) was conducted to examine the direct and indirect effects of COVID-19 distress on suicidality via psychosocial and financial well-being. Results: The direct effect of COVID-19 distress on suicidality was not significant (β = 0.022, 95% CI − 0.097–0.156). The total indirect effect from COVID-19 distress to suicidality was significant and positive (αβγ = 0.150, 95% CI = 0.085–0.245) and accounted for 87% of the total effect (B = 0.172, 95% CI = 0.043–0.341). There were significant specific indirect effects via social well-being and psychological distress, and financial well-being and psychological distress. Conclusion: The present findings support different pathways from COVID-19 distress to suicidality via functioning in different domains among young people in Hong Kong. Measures are needed to ameliorate the impact on their social and financial well-being to reduce their psychological distress and suicidality. [ABSTRACT FROM AUTHOR]

This research investigated the relationships of the Dark Triad traits, humor styles, and schadenfreude with 169 participants who completed the Short Dark Triad, the Humor Style Questionnaire, and a measure of schadenfreude. Significant correlations imply that those with salient dark traits (psychopathy, Machiavellianism, narcissism) elicit pleasure from others' misfortune. Additionally, schadenfreude can be a product of self‐defeating and aggressive humor styles. Indirect effect analysis revealed the significance of the indirect effect of the measured aggressive humor style on the Dark Triad's direct effects on schadenfreude. These results imply that those with salient Dark Triad traits enjoy others' misery as a means to undermine them. Hence, individuals with salient Dark Triad traits tend to engage in downward social comparison. [ABSTRACT FROM AUTHOR]

BackgroundPeople with HIV (PWH) are at increased risk for invasive pneumococcal disease (IPD). Thirteen-valent pneumococcal conjugate vaccine (PCV13) was recommended for use in US children in 2010 and for PWH aged 19 years or older in 2012. We evaluated the population-level impact of PCV13 on IPD among PWH and non-PWH aged 19 years or older.MethodsWe identified IPD cases from 2008 to 2018 through the Active Bacterial Core surveillance platform. We estimated IPD incidence using the National HIV Surveillance System and US Census Bureau data. We measured percent changes in IPD incidence from 2008 to 2009 to 2017-2018 by HIV status, age group, and vaccine serotype group, including serotypes in recently licensed 15-valent (PCV15) and 20-valent (PCV20) PCVs.ResultsIn 2008-2009 and 2017-2018, 8.4% (552/6548) and 8.0% (416/5169) of adult IPD cases were among PWH, respectively. Compared with non-PWH, a larger proportion of IPD cases among PWH were in adults aged 19-64 years (94.7%-97.4% vs. 56.0%-60.1%) and non-Hispanic Black people (62.5%-73.0% vs. 16.7%-19.2%). Overall and PCV13-type IPD incidence in PWH declined by 40.3% (95% confidence interval: -47.7 to -32.3) and 72.5% (95% confidence interval: -78.8 to -65.6), respectively. In 2017-2018, IPD incidence was 16.8 (overall) and 12.6 (PCV13 type) times higher in PWH compared with non-PWH; PCV13, PCV15/non-PCV13, and PCV20/non-PCV15 serotypes comprised 21.5%, 11.2%, and 16.5% of IPD in PWH, respectively.ConclusionsDespite reductions post-PCV13 introduction, IPD incidence among PWH remained substantially higher than among non-PWH. Higher-valent PCVs provide opportunities to reduce remaining IPD burden in PWH.

Evolutionary rescue may allow species to survive environmental change, but how this mechanism operates in food webs is poorly understood. Here, the evolutionary rescue was investigated in a small model food web, systematically allowing the evolution of each single species in order to reveal how its adaptation affects the persistence of itself and others. The impact of evolution was highly species‐specific and not necessarily positive: only one species, the specialist predator, consistently had a positive impact on overall persistence. Most strikingly, evolution overwhelmingly affected other species: rescue of others (indirect rescue) was far more frequent than self‐rescue, and negative effects were nearly always indirect. This demonstrates that evolutionary rescue in food webs is inextricably bound up with species interactions, as the effects of evolution in one species ripple through the entire community. It is therefore critically important to consider the food web context in efforts to understand how species may survive global change. [ABSTRACT FROM AUTHOR]

Indirect interactions are widespread among prey species that share a common predator, but the underlying mechanisms driving these interactions are often unclear, and our ability to predict their outcome is limited.Changes in behavioural traits that impact predator space use could be a key proximal mechanism mediating indirect interactions, but there is little empirical evidence of the causes and consequences of such behavioural‐numerical response in multispecies systems.Here, we investigate the complex ecological relationships between seven prey species sharing a common predator. We used a path analysis approach on a comprehensive 9‐year data set simultaneously tracking predator space use, prey densities and prey mortality rate on key species of a simplified Arctic food web.We show that high availability of a clumped and spatially predictable prey (goose eggs) leads to a twofold reduction in predator (arctic fox) home range size, which increases local predator density and strongly decreases nest survival of an incidental prey (American golden plover). On the contrary, a scattered cyclic prey with potentially lower spatial predictability (lemming) had a weaker effect on fox space use and an overall positive impact on the survival of incidental prey.These contrasting effects underline the importance of studying behavioural responses of predators in multiprey systems and to explicitly integrate behavioural‐numerical responses in multispecies predator–prey models. [ABSTRACT FROM AUTHOR]

Abstract Prior research has suggested that clustered regression discontinuity designs are a formidable alternative to cluster randomized designs because they provide targeted treatment assignment while maintaining a high-quality basis for inferences on local treatment effects. However, methods for the design and analysis of clustered regression discontinuity designs have not been fully developed to address the array of core effects (e.g., main, moderation and mediation) typically examined in education studies. In this study, we complement prior design literature by developing principles of estimation, sampling variability, and closed-form expressions to predict the statistical power to detect mediation effects in clustered regression discontinuity designs. The results suggest that sample sizes typically seen in educational intervention studies (e.g., about 50 schools) can be sufficient to detect a mediation effect under some conditions when studies are carefully designed. We implement the results in software and a Shiny App (BLINDED FOR REVIEW). [ABSTRACT FROM AUTHOR]

Concerns regarding vaccine effects on microbial ecology have led to interest in the non-targeted effects of vaccinations. To systematically review the literature related to the impact of vaccines on S. aureus carriage. We conducted a systematic search of MEDLINE, Scopus and clinical trials.gov for studies that assessed vaccine effects on S. aureus carriage in children and adults using predefined inclusion and exclusion criteria. Generic inverse variance meta -analysis was done using random-effects models. Of 1,686 studies screened, 34 were eligible for inclusion, of which 22 were observational and 12 randomized controlled studies (RCTs). 88.2% (30/34) provided data on pneumococcal conjugate vaccines (PCV), 23.5% on influenza vaccines (8/34), 6% on other vaccines (2/34) and 20.6% on more than one vaccine (7/34). Most studies tested nasopharyngeal specimens (82.3%, 28/34). Among children aged more than 18–24 months, evidence suggested no effect of PCV on S. aureus colonization [2 RCTs, pooled OR 1.09 (95% CI 0.94–1.25), p 0.25; 7 observational studies, pooled OR: 1.02 (95% CI 0.83–1.25), p 0.86]. A transient increase in S. aureus carriage in PCV-vaccinated infants 9–15 months was shown [2 RCTs, pooled OR 1.11 (95% CI 1.00–1.23), p 0.06; 4 observational studies, pooled OR 1.64 (95% CI 1.00–2.68), p 0.05]. A reduction in S. aureus carriage was observed after influenza vaccination [4 observational studies; OR 0.85 (95% CI 0.78–0.94), p 0.0001]. Based on the Grading of Recommendations Assessment, Development and Evaluation, the quality of evidence was considered low for randomized and very low for non-randomized trials. Evidence did not suggest long-term effects of pneumococcal vaccinations on S. aureus nasopharyngeal carriage in children, however transient niche changes may occur in infants. Influenza vaccination was related to decreased rates of S. aureus carriage. Data regarding other vaccines is scarce. Further research and ongoing surveillance are needed to monitor colonization changes. [ABSTRACT FROM AUTHOR]

Although the keystone species concept was conceived of over 50 years ago, contemporary efforts to synthesize related literature have been limited. Our objective was to create a list of keystone animal species identified in the literature and to examine the variation in the traits of species and the ecosystem influences they elicit. We documented 230 species considered keystones. A clustering analysis classified them into five archetypes based on combinations of their taxonomic class, body size, trophic level, and role (consumers, modifiers, or prey). Although conservation and public perception of keystones primarily focuses on large vertebrate consumers, our analysis reveals that researchers have defined a wide diversity of keystone species, with large variation in associated ecosystem processes. Future research may confront ambiguity in the definition of keystone status, as well as clarify the type, abundance, and quality of data required to assign the term. Identifying keystones with increased rigor would not only enrich the literature but also inform intervention to safeguard threatened keystones and their associated influences on ecosystems. [ABSTRACT FROM AUTHOR]

Mediation analysis is widely used to test and inform theory and debate about the mechanism(s) by which causal effects operate, quantitatively operationalized as an indirect effect in a mediation model. Most effects operate through multiple mechanisms simultaneously, and a mediation model is likely to be more realistic when it is specified to capture multiple mechanisms at the same time with the inclusion of more than one mediator in the model. This also allows an investigator to compare indirect effects to each other. After an overview of the mechanics of mediation analysis, we advocate formally comparing indirect effects in models that include more than one mediator, focusing on the important distinction between questions and claims about value (i.e., are two indirect effects the same number?) versus magnitude (i.e., are two indirect effects equidistant from zero or the same in strength?). After discussing the shortcomings of the conventional method for comparing two indirect effects in a multiple mediator model—which only answers a question about magnitude in some circumstances—we introduce several methods that, unlike the conventional approach, always answer questions about difference in magnitude. We illustrate the use of these methods and provide code that implements them in popular software. We end by summarizing simulation findings and recommending which method(s) to prefer when comparing like- and opposite-signed indirect effects. [ABSTRACT FROM AUTHOR]

Microorganisms associated with plant roots significantly impact the quality and quantity of plant defences. However, the bottom-up effects of soil microbes on the aboveground multitrophic interactions remain largely under studied. To address this gap, we investigated the chemically-mediated effects of nitrogen-fixing rhizobia on legume-herbivore-parasitoid multitrophic interactions. To address this, we initially examined the cascading effects of the rhizobia bean association on herbivore caterpillars, their parasitoids, and subsequently investigated how rhizobia influence on plant volatiles and extrafloral nectar. Our goal was to understand how these plant-mediated effects can affect parasitoids. Lima bean plants (Phaseoulus lunatus) inoculated with rhizobia exhibited better growth, and the number of root nodules positively correlated with defensive cyanogenic compounds. Despite increase of these chemical defences, Spodoptera latifascia caterpillars preferred to feed and grew faster on rhizobia-inoculated plants. Moreover, the emission of plant volatiles after leaf damage showed distinct patterns between inoculation treatments, with inoculated plants producing more sesquiterpenes and benzyl nitrile than non-inoculated plants. Despite these differences, Euplectrus platyhypenae parasitoid wasps were similarly attracted to rhizobia- or no rhizobia-treated plants. Yet, the oviposition and offspring development of E. platyhypenae was better on caterpillars fed with rhizobia-inoculated plants. We additionally show that rhizobia-inoculated common bean plants (Phaseolus vulgaris) produced more extrafloral nectar, with higher hydrocarbon concentration, than non-inoculated plants. Consequently, parasitoids performed better when fed with extrafloral nectar from rhizobia-inoculated plants. While the overall effects of bean-rhizobia symbiosis on caterpillars were positive, rhizobia also indirectly benefited parasitoids through the caterpillar host, and directly through the improved production of high quality extrafloral nectar. This study underscores the importance of exploring diverse facets and chemical mechanisms that influence the dynamics between herbivores and predators. This knowledge is crucial for gaining a comprehensive understanding of the ecological implications of rhizobia symbiosis on these interactions.

Abstract Understory assemblages associated with canopy‐forming species such as trees, kelps, and rockweeds should respond strongly to climate stressors due to strong canopy‐understory interactions. Climate change can directly and indirectly modify these assemblages, particularly during more stressful seasons and climate scenarios. However, fully understanding the seasonal impacts of different climate conditions on canopy‐reliant assemblages is difficult due to a continued emphasis on studying single‐species responses to a single future climate scenario during a single season. To examine these emergent effects, we used mesocosm experiments to expose seaweed assemblages associated with the canopy‐forming golden rockweed, Silvetia compressa, to elevated temperature and pCO2 conditions reflecting two projected greenhouse emission scenarios (RCP 2.6 [low] & RCP 4.5 [moderate]). Assemblages were grown in the presence and absence of Silvetia, and in two seasons. Relative to ambient conditions, predicted climate scenarios generally suppressed Silvetia biomass and photosynthetic efficiency. However, these effects varied seasonally—both future scenarios reduced Silvetia biomass in summer, but only the moderate scenario did so in winter. These reductions shifted the assemblage, with more extreme shifts occurring in summer. Contrarily, future scenarios did not shift assemblages within Silvetia Absent treatments, suggesting that climate primarily affected assemblages indirectly through changes in Silvetia. Mesocosm experiments were coupled with a field Silvetia removal experiment to simulate the effects of climate‐mediated Silvetia loss on natural assemblages. Consistent with the mesocosm experiment, Silvetia loss resulted in season‐specific assemblage shifts, with weaker effects observed in winter. Together, our study supports the hypotheses that climate‐mediated changes to canopy‐forming species can indirectly affect the associated assemblage, and that these effects vary seasonally. Such seasonality is important to consider as it may provide periods of recovery when conditions are less stressful, especially if we can reduce the severity of future climate scenarios.

Abstract Introduction This study estimates the annual population-level impact of 13-valent pneumococcal conjugate vaccine (PCV13) infant national immunization programs (NIPs) on vaccine-type and non-vaccine type invasive pneumococcal disease (IPD) incidence across all ages using national surveillance data. Methods We identified countries (Australia, Canada, England and Wales, Israel, and the US) with national IPD active surveillance data that introduced the seven-valent PCV (PCV7) followed by PCV13, which also reported annual serotype- and age group-specific incidence. We extracted IPD incidence by serotype groupings [PCV13 minus PCV7 (PCV13-7) serotypes; PCV13-7 serotypes excluding serotype 3; non-PCV13 serotypes; and the 20-valent (PCV20) minus PCV13 (PCV20-13) serotypes] and by age groups (