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A multiwavelength evaluation of AGN in the post-starburst phase
No full textThe quenching of star formation is a crucial phase in galaxy evolution. Although feedback from active galactic nuclei (AGN) has been proposed as a key driver of this transition, the lack of strong AGN in nearby quenching galaxies raises questions about its effectiveness. In this study, we investigate AGN activity in post-starburst galaxies (PSBs), star-forming galaxies (SFGs), and quiescent galaxies (QGs) at z < 0.2, using multiwavelength data from eROSITA Final Equatorial Depth Survey (X-ray), Wide-field Infrared Survey Explorer (mid-infrared), and Faint Images of the Radio Sky at Twenty cm (radio). We assess AGN incidence and strength across different stages and apply stacking techniques to undetected galaxies to recover average AGN properties. Comparisons between observed luminosity and that expected from star formation (Lobs/LSF) show that PSBs are consistent with star formation dominating their radio and X-ray emission. Although PSBs exhibit a mid-infrared (MIR) AGN incidence rate twice that of SFGs, their estimated AGN luminosities are small compared to those of MIR AGN in the literature. PSBs overall do not display significantly enhanced AGN emission relative to mass- and redshift-matched SFGs and QGs. While the presence of obscured, low-luminosity AGN in PSBs cannot be excluded, such AGN, if present, could be fueled by residual gas from the preceding starburst and may not play a dominant role in quenching. Our findings suggest that the role of AGN in quenching at low redshift is more subtle than violently removing the gas—the feedback is likely more “preventive” than “ejective.
Swapped and non-swapped TRAAK states co-exist in membranes at a ratio influenced by temperature
No full textThe potassium two-pore domain (K2P) ion channel TRAAK is expressed in the nervous system and regulates the fast action potential in membranes. Like all K2P channels, TRAAK possesses a distinct extracellular cap, which adopts a swapped and a non-swapped conformation1,2. However, the proportional representation of these two species within native membranes – and the trigger or stimulus associated with this conformational transition – are unknown. Here, we utilise Pulse Dipolar EPR Spectroscopy combined with heterologous single-subunit spin-labelling and monitor the complete conformational ensemble of TRAAK’s cap domain in membranes. We demonstrate the coexistence of the swapped and non-swapped states, quantify their populations within the TRAAK ensemble, and show that the swapped conformation dominates, with the ratio being influenced by temperature. Native lipid analysis shows that TRAAK selectively associates with and is activated by signalling lipids to the exclusion of membrane-dominant phosphatidylcholine lipids from its vicinity, forming a distinct microdomain. Our approach can identify the immediate lipid environment, detect and quantify cap state populations in homo-/hetero-K2P channels and link domain swapping to specific triggers
The role of English seabed sediments in carbon storage, impact of human activities, environmental pressures and potential management options: Evidence review
No full textThe evidence surrounding organic carbon (hereby referred to as “OC”) storage in subtidal seabed sediments and the potential impact from human activities, and climate itself, is growing at pace. This technical briefing assesses the current evidence base, providing confidence levels and options for how this might direct potential next steps. It will inform the direction of Defra’s work in the UK and internationally to identify and fill key evidence gaps collaboratively through existing and future programmes. This briefing also identifies a range of measures which could be taken to protect subtidal seabed sediment OC as a nature-based solution to climate change and highlights potential trade-offs
Large Language Models Persuade Without Planning Theory of Mind
No full textA growing body of work attempts to evaluate the theory of mind (ToM) abilities of humans and large language models (LLMs) using static, non-interactive question-and-answer benchmarks. However, theoretical work in the field suggests that first-personal interaction is a crucial part of ToM and that such predictive, spectatorial tasks may fail to evaluate it. We address this gap with a novel ToM task that requires an agent to persuade a target to choose one of three policy proposals by strategically revealing information. Success depends on a persuader's sensitivity to a given target's knowledge states (what the target knows about the policies) and motivational states (how much the target values different outcomes). We varied whether these states were Revealed to persuaders or Hidden, in which case persuaders had to inquire about or infer them. In Experiment 1, participants persuaded a bot programmed to make only rational inferences. LLMs excelled in the Revealed condition but performed below chance in the Hidden condition, suggesting difficulty with the multi-step planning required to elicit and use mental state information. Humans performed moderately well in both conditions, indicating an ability to engage such planning. In Experiment 2, where a human target role-played the bot, and in Experiment 3, where we measured whether human targets' real beliefs changed, LLMs outperformed human persuaders across all conditions. These results suggest that effective persuasion can occur without explicit ToM reasoning (e.g., through rhetorical strategies) and that LLMs excel at this form of persuasion. Overall, our results caution against attributing human-like ToM to LLMs while highlighting LLMs' potential to influence people's beliefs and behavior
An active matter model captures spatial dynamics of actomyosin oscillations in larval epithelial cells during <i>Drosophila</i> morphogenesis
No full textThe apicomedial actomyosin network is crucial for generating mechanical forces in cells. Oscillatory behavior of this contractile network is commonly observed before or during significant morphogenetic events. For instance, during the development of the Drosophila adult abdominal epidermis, larval epithelial cells (LECs) undergo pulsed contractions before being replaced by histoblasts. These contractions involve the formation of contracted regions of concentrated actin and myosin. The emergence and control of pulsed contractions are not fully understood. Here, we combined in vivo 4D microscopy with numerical simulations of an active elastomer model applied to realistic cell geometries and boundary conditions informed by cell polarity to study in vivo subcellular spatial patterns of LEC actomyosin dynamics. The active elastomer model quantitatively reproduced in vivo observations. When compared to rectangular domains, simulations on realistic cell geometries showed systematically better agreement with experiments. We found that cell shape, cell polarity, and organization of the cell’s actomyosin network codetermine spatiotemporal network dynamics both in vivo and in simulations. Furthermore, the model predicted changes to LEC contractile activity under genetic perturbation of the actomyosin network. Our results show that cell geometry, accompanied by boundary conditions which reflect the cells’ polarity, is important to understanding the dynamics of the apicomedial actomyosin network. Moreover, our findings support the notion that spatiotemporal oscillatory behavior of the actomyosin network is an emergent property of the actomyosin network, rather than driven by upstream signaling
Generation of iterated wreath products constructed from alternating, symmetric and cyclic groups
No full textLet G1, G2, … be a sequence of groups each of which is either an alternating group, a symmetric group or a cyclic group. Let us construct a sequence (Wi) of wreath products via W1 = G1 and, for each i ≥ 1, Wi+1 = Gi+1 wr Wi via the natural permutation action. We determine the minimum number d(Wi) of generators required for each wreath product in this sequence
Transitions in and out of loneliness during the COVID-19 pandemic:a latent class analysis of older adults in England
No full textDisease control measures during the COVID-19 pandemic may have intensified loneliness among older adults, though experiences varied based on individual vulnerabilities and resources. This study examines loneliness trajectories among older adults using the English Longitudinal Study of Ageing, spanning four waves: two pre-pandemic (Wave 8: 2016–2017; Wave 9: 2018–2019) and two COVID-19 substudies (June–July and November–December 2020). The sample included 4492 respondents (17,968 observations). Latent class growth analysis identified four loneliness trajectories: ‘not lonely’ (73.5%), ‘pandemic loneliness’ (12.7%), ‘transitioned out of loneliness’ (6.9%) and ‘enduring loneliness’ (6.8%). Multinomial regression analysis explored predictors of trajectory membership. Younger age (50–74), being female, depression, COVID-related worries and disrupted daily routines increased the likelihood of belonging to ‘pandemic loneliness’ rather than ‘not lonely’. Optimism and strong partner support increased the likelihood of remaining ‘not lonely’ or transitioning out of loneliness. The pandemic's unintended effects, including routine disruptions and financial concerns, heightened loneliness risks, whereas psychosocial resources provided critical resilience. To prepare for future public health crises, policies should strengthen mental health support, promote social and economic stability and enhance social connection and resilience. Addressing psychosocial factors is essential to reducing loneliness and protecting older adults' well-being during and beyond periods of crisis
Endemic fish promote ecological structure in a tropical biodiversity hotspot
No full textEndemic species enrich biodiversity hotspots, but how do they contribute to biodiversity structure at macroecological scales? Here, we argue that classifying endemic species using a framework defined by the complementary axes of taxonomic and functional diversity is key to revealing how these patterns underpin community convergence and divergence. These processes are known to configure communities to be compositionally more similar or dissimilar, respectively. Using the endemic freshwater fish communities of India’s Western Ghats Escarpment (WGE), one of the 'hottest' spots of global biodiversity, as a test case, we find that geographically widespread, trait-distinct endemics are disproportionately present in the west-flowing basins of the WGE where they promote overall convergence (i.e. both taxonomic and functional). In contrast, among east-flowing basins, a lower-than-expected occurrence of the same category of species supports taxonomic divergence and functional convergence. We attribute this heterogeneity to western-flowing basins having higher (i) ecosystem productivity that supports trait-distinctiveness, and (ii) temporary lateral connectivity that facilitates fish dispersal. Our study demonstrates how different dimensions of diversity interact to produce ecological structure, thereby underlining their role in resilience. Thus, this framework has application in conservation and policy and can guide global efforts to protect endemic biodiversity in hotspots
Local specialists’ experience and skills in animal behaviour studies:insights from wild chimpanzee field assistants
No full textThe study of wild animal behaviour and cognition has greatly benefited from the foundational work of local specialists (LSs), particularly field assistants. In primate research, long-term studies rely on accurate identification and tracking of individuals—a skill often honed by LSs and passed on to international specialists (ISs). Despite growing recognition in publications, LSs’ scientific contributions often remain undervalued. Here, we show that LSs at the Budongo Conservation Field Station (Uganda) reliably extract acoustic information (caller identity, sex and age, call components and production context) from long-distance pant hoot calls produced by wild chimpanzees. Importantly, LSs significantly outperform ISs at identifying individuals (LS accuracy = 50% [95% CI: 45–56%]; IS accuracy = 8% [95% CI: 5–11%]), an important skill for recognising and locating individuals in dense forests. LSs’ performance was positively associated with duration of working experience. Given the limited field time of ISs (typically 1-2 years), LSs’ expertise and longer commitment (mean 16.75 years) represent an essential yet underacknowledged scientific resource. Our study highlights LSs’ critical role in ethological research—not only enhancing skills and data quality, but also potentially helping address both ethical (e.g., community involvement) and environmental (e.g., travel carbon footprint) challenges linked to fieldwork in remote locations
Beware the Toll dodgers:defending the Tollgate Principles for governing solar geoengineering
No full textThe Tollgate Principles (‘TGPs’) aim to represent ‘the price that must be paid’ by anyone claiming to be ethically serious about pursuing solar geoengineering (Gardiner and Fragnière, Ethic Policy Environ 221(2):143–174, 2018). The TGPs are influential but, like other governance principles, have also provoked criticism. This paper clarifies the Tollgate approach by responding to objections and dissolving some perceived tensions. It argues that, while not the final word, the TGPs are an important step in the evolution of geoengineering governance and should continue to be taken seriously at all levels. It concludes that rather than “beware the Toll Keepers” (Briggle, Ethic Policy Environ 21(2):187–189, 2018) we should instead “beware the Toll Dodgers”: those who would brush aside the TGPs and other ethics-centered approaches. As well as defending the Tollgate approach specifically, the discussion provides broader lessons for governing geoengineering and other controversial technological interventions
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