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Catastrophic collapses of top predators have revealed trophic cascades and community structuring by top-down control. When populations fail to recover after a collapse, this may indicate alternative stable states in the system. Overfishing has caused several of the most compelling cases of these dynamics, and in particular Atlantic cod stocks exemplify such lack of recovery. Often, competition between prey species and juvenile predators is hypothesized to explain the lack of recovery of predator populations. The predator is then considered to compete with its prey for one resource when small and to subsequently shift to piscivory. Yet predator life history is often more complex than that, including multiple ontogenetic diet shifts. Here we show that no alternative stable states occur when predators in an intermediate life stage feed on an additional resource (exclusive to the predator) before switching to piscivory, because predation and competition between prey and predator do not simultaneously structure community dynamics. We find top-down control by the predator only when there is no feedback from predator foraging on the additional resource. Otherwise, the predator population dynamics are governed by a bottleneck in individual growth occurring in the intermediate life stage. Therefore, additional resources for predators may be beneficial or detrimental for predator population growth and strongly influence the potential for top-down community control.
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http://dx.doi.org/10.1086/670614 | DOI Listing |
Mem Cognit
September 2025
Department of Psychology, University of York, York, YO10 5DD, UK.
Language control has been argued to adapt dynamically to the language context bilinguals are communicating in (Green & Abutalebi, 2013). Previous research has suggested that the demands of the task and current context itself can influence a bilingual's language behaviour and potentially also their language control. Here, we examined how the preceding context, specifically the switching patterns of another bilingual in that context, can influence a bilingual's own language control during production.
View Article and Find Full Text PDFJ Neurosci
September 2025
Lendület Laboratory of Thalamus Research, HUN-REN Institute of Experimental Medicine; Budapest, Hungary
The paraventricular thalamic nucleus (PVT) integrates subcortical signals related to arousal, stress, addiction, and anxiety with top-down cortical influences. Increases or decreases in PVT activity exert profound, long-lasting effects on behavior related to motivation, addiction and homeostasis. Yet the sources of its subcortical excitatory and inhibitory afferents, their distribution within the PVT, and their integration with layer-specific cortical inputs remain unclear.
View Article and Find Full Text PDFACS Nano
September 2025
Frontiers Science Center for Transformative Molecules, State Key Laboratory of Synergistic Chem-Bio Synthesis, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai 200240, P. R. China.
Dynamic micro/nano-structured surfaces play pivotal roles in biological systems and engineering applications. Despite considerable progress has been made in fabricating precisely ordered architectures, achieving controlled motion in top-down fabricated structures remain a formidable challenge. Here, we introduce an advanced dynamic micron-nano optical platform featuring hierarchical microscale wrinkles integrated with ordered nanoscale arrays.
View Article and Find Full Text PDFOpen Access J Contracept
September 2025
Coordinator for Centre for SET-SRHR Lira University, Lira, Uganda.
Background: Conventional top-down health interventions often exclude adolescents and community stakeholders from service design and implementation, resulting in low uptake and a mismatch with young people's needs. The CAFFP-PAC initiative in Northern Uganda sought to explore how a community-led, adolescent-centered inception process could support integration of adolescent-friendly family planning and post-abortion care into primary healthcare services.
Methods: A participatory qualitative design was employed during an inception meeting in Lira City on April 1, 2025, guided by principles of community-based participatory research and citizen science.
PLoS One
September 2025
CIRAD, UMR ASTRE, Montpellier, France.
Since the 2013-2014 Ebola virus disease outbreak, Guinea has faced recurrent epidemics of viral hemorrhagic fevers. Although the country has learned from these epidemics by improving its disease surveillance and investigation capacities, local authorities and stakeholders, including community actors, are not sufficiently involved in the disease-emergence response. As a result, measures are not fully understood and have failed to engage local stakeholders.
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