Royal Society Open Science最新文献

Cues related to financial scarcity are commonly present in the daily environment shaping people's mental lives. However, prior findings are mixed on whether such scarcity-related cues disproportionately deteriorate the cognitive performance of poorer versus richer individuals. In our registered report, we collected a large study sample (N = 4280) using targeted sampling strategies to reach a diverse group of people along education and financial status. We focused on attentional performance to-compared to prior studies-more sensitively assess the effect of even brief lapses of attention. Using words related to absolute scarcity (poverty) and relative scarcity (abundance) as cues, we found strong evidence against the existence of a different effect on the sustained attentional performance between poorer and richer participants. The utilized cues facilitated scarcity-related thoughts but not financial worries, which may explain the absence of the effect. The findings were robust across various analytical choices, including the used outcome variable, exclusion criteria, outlier treatment and used socioeconomic indicators. Our results suggest that, in online contexts, exposure to scarcity-related words does not differentially impact sustained attentional performance across socioeconomic groups, highlighting important boundaries to the generalizability of scarcity theory.

Pineapple (Ananas comosus) peel, an abundant agro-industrial by-product, offers significant potential as a sustainable natural dye for textile applications. This study optimized colourant extraction using an alkaline-water system and evaluated dyeing performance on cotton fabrics. Statistical optimization through four-factor linear regression identified optimal conditions: mass-to-liquid ratio of 1 : 10, 12% NaOH, 80°C and 2 h extraction time, yielding 35-40% colourant, significantly outperforming organic solvents (<1%). High-performance liquid chromatography analysis revealed distinctive polyphenolic profiles between alkaline and water extraction methods, demonstrating altered compound distribution and enhanced extraction efficiency under alkaline conditions. Thermogravimetric analysis revealed dye stability up to 160°C, while particle size analysis showed a mean size of 266 nm, enabling effective fibre penetration. Quantitative dyeing evaluation demonstrated 43.05% exhaustion, 27.76% total fixation efficiency and 0.64 fixation ratio. Colorimetric analysis revealed significant mordant-dependent variations, with tannic acid achieving superior colour strength (K/S = 21.4) compared to metallic mordants: zinc sulfate, alum and ammonium ferrous sulfate. CIELab coordinates confirmed successful dye uptake (L* = -6.92 to -12.83). Post-mordanting with zinc sulfate achieved excellent fastness properties: wash (4-5), light (4) and rubbing (4) fastness. Cationization minimized electrostatic repulsion between cotton and anionic dye molecules, enhancing dye absorption. The findings demonstrate pineapple peel waste viability as a cost-effective natural dye with quantified performance metrics supporting commercial feasibility and circular economy principles in sustainable textile manufacturing.

According to current theory and experiments, cooperation is more likely to evolve when organisms can choose to replace uncooperative partners with cooperative ones. However, there is a downside to this partner choice: when partners can be easily replaced, organisms have less stake in their partners' welfare and will therefore be less likely to help keep those partners alive and well enough to reciprocate. Here, I present a mathematical model showing that when a third party is present, organisms will provide more observable help to their partners (reciprocity/signalling-based helping), but less anonymous help that would keep that partner in good condition (stake-based helping). The net effect of partner choice depends on the relative strength of these two factors: partner choice has a more positive effect if interactions are short (i.e. less stake), when observers judge based on observed helping (i.e. reputation matters), and when one can have multiple cooperative partners at the same time. These results show the importance of differentiating between helping that relies on observation (e.g. reciprocity and signalling), helping that requires no observation (e.g. kinship and stake), and how the two types interact.

Social media platforms like YouTube and Twitter play a key role in disseminating both reliable and unreliable information about climate change. This study analyses the topology of interactions in Twitter and their relation to cross-platform sharing, content discussions and emotional responses. We examined climate change discussions across four topics: the 27th United Nations Climate Change Conference, the Sixth Assessment Report of the United Nations Intergovernmental Panel on Climate Change, Climate Refugees and Doñana Natural Park. While retweets reinforce in-group cohesion in the form of echo chambers, inter-group exposure is significant through mentions, suggesting that exposure to opposing views intensifies polarization, rather than mitigates it. Ideological divides feature content differences accompanied by steeper negative sentiments, especially from right-leaning communities prone to share low-reliability information. We identified a topological and thematic alignment between platforms, indicating that ideological communities are interconnected across them. Our findings show that climate change polarization is multifaceted, involving ideological divides, structural isolation and emotional engagement. These results suggest that effective climate policy discussions must address the emotional and identity-driven nature of public discourse and seek strategies to bridge ideological divides.

Annually, 14-41 per 100 000 infants get mildly to lethally injured or severely disabled through violent shaking. The incidence and mortality of inflicted head injury by shaking trauma (IHI-ST) are highest in the early months and decrease with age. This may partly be due to the age-related physical characteristics of infants. Younger, smaller infants are more vulnerable owing to their size and material properties. In addition, from basic biomechanics, it is expected that larger or heavier infants may be more difficult to fiercely shake and will exhibit different motion patterns when being shaken violently. Therefore, the aim of this study was to compare the kinematics of shaking a smaller versus a larger infant dummy. We recorded the kinematics of two dummies, representing a 6-week-old and a 1-year-old, while they were violently shaken by volunteers. We found that participants induced higher head and torso accelerations when shaking the 6-week-old, than with the 1-year-old dummy. Moreover, higher peak sagittal angular accelerations coincide with smaller radii of rotation in the 6-week-old than in the 1-year-old. Because it has been suggested in the literature that sagittal angular acceleration of the head is an important mechanism in inducing the injuries associated with IHI-ST; the results of this study show that shaking a smaller/younger infant is more likely to cause the kinematics possibly responsible for IHI-ST.

The spread of misinformation on social media continues to pose challenges. While prior research has shown some success in reducing susceptibility to misinformation at scale, how individual-level interventions impact the quality of content shared on social networks remains understudied. Across two pre-registered longitudinal studies, we ran two Twitter/X ad campaigns, targeting a total of 967 640 Twitter/X users with either a previously validated 'inoculation' video about emotional manipulation or a control video. We hypothesized that Twitter/X users who saw the inoculation video would engage less with negative-emotional content and share less content from unreliable sources. We do not find evidence for our hypotheses, observing no meaningful changes in posting or retweeting post-intervention. Our findings are most likely compromised by Twitter/X's 'fuzzy matching' policy, which introduced substantial noise in our data (approx. 7.5% of targeted individuals were actually exposed to the intervention). Our findings are thus probably the result of treatment non-compliance rather than 'true' null effects. Importantly, we also demonstrate that different statistical analyses and time windows (looking at the intervention's effects over 1 h versus 6 h or 24 h, etc.) can yield different and even opposite significant effects, highlighting the risk of interpreting noise from field studies as signal.

Gambusia nobilis is a federally endangered species found across a fragmented distribution within the Pecos River Drainage of Texas and New Mexico, USA. Drought, human water usage, and potential hybridization and competition with introduced congeners threaten species persistence. Therefore, a population genomics study was conducted to provide critical information for conservation planning. Unsupervised clustering suggested hierarchical structure, with a primary K = 3, and deep divergences were detected among samples grouped into the Leon Creek watershed, the Toyah Creek watershed, and water bodies within the Bitter Lake National Wildlife Refuge (F' _ST = 0.55-0.76 for putatively neutral data). Phylogenetic analyses showed three distinct clades corresponding to these groups, with divergence times estimated to be in the last 50 000 years. Complimentary morphological analyses detected differences among the three groups, including features of male colour pattern, and the number of caudal-fin rays in both sexes. Taken as a whole, the results indicate that the endangered G. nobilis comprises three species (two of which are named herein as G. pyrros n. sp. and G. echelleorum n. sp.), rather than one, and the study highlights the daunting yet critical task of documenting species diversity during a period of unprecedented diversity loss.

Alarm calls are a common, widely studied antipredator behaviour, with species producing different call types that can have distinct functions. Here, we describe a new type of alarm call in the superb fairy-wren (Malurus cyaneus), the 'seet' danger call. We (i) describe the acoustic characteristics and context of the danger call (in comparison with two other alarm calls); (ii) test its occurrence in relation to predator proximity to nest and nesting stage; and (iii) test the response of birds to experimental broadcast of aerial versus danger calls, given their similar acoustic structure. The danger call is a high-frequency, down-sweep call. Danger calls were produced in all nesting stages, with more calls given when the human threat was closer to the nest. Most danger calls were produced during the feeding phase, and the fewest were produced after fledging. Groups produced more danger calls when responding to experimental broadcasts of danger versus aerial calls. We propose that the 'seet' danger call functions as a warning to conspecifics of a threat approaching immobile or moderately mobile and, hence, vulnerable individuals. The occurrence of a nest-based alarm call that covaries with nest content raises the question of which cues adults use to assess offspring vulnerability.

Three 2'-hydroxychalcone derivatives were synthesized via microwave-assisted organic synthesis using the ionic liquid 1-decyl-3-methylimidazolium bromide ([DMIm]Br) as the medium. The reactions, conducted at 80°C under 300 W microwave power for 10 min, yielded products with yields of 65, 72 and 81%. A computational study using density functional theory with B3LYP and ωB97X functionals examined the reactivity of precursors via Fukui function analysis. Results showed that higher reactivity of benzaldehyde derivatives correlated with increased product yields: o-vanillin > anisaldehyde > salicylaldehyde. The cyclization of 2,2'-dihydroxy-3-methoxychalcone to its flavanone derivative was also simulated, revealing a two-step mechanism with the first step being rate-determining (activation energy: 63.8 kJ mol^-1). Additionally, the formation of [DMIm]Br was found to proceed through an S_N2 mechanism, with an activation energy of 197.3  kJ mol^-1. These experimental and computational findings underscore the predictive power of Fukui-based reactivity in optimizing chalcone synthesis in ionic liquid media.

Heat stress can disrupt acid-base homeostasis in reef-building corals and other tropical cnidarians, often leading to cellular acidosis that can undermine organismal function. Temperate cnidarians experience a high degree of seasonal temperature variability, leading us to hypothesize that temperate taxa have more thermally robust pH homeostasis than their tropical relatives. To test this, we investigated how elevated temperature affects intracellular pH and calcification in the temperate coral Astrangia poculata. Clonal pairs were exposed to elevated (30°C) or control (22°C) temperatures for 17 days. Despite causing damage to host tissues and symbiont cells, elevated temperature did not affect intracellular pH or inhibit calcification in A. poculata. These responses contrast with those of tropical cnidarians, which experience cellular acidification and decreased growth during heat stress. Astrangia poculata therefore appears to have thermally resilient cellular acid-base homeostasis mechanisms, possibly because of adaptation to large seasonal temperature variations. However, we also observed tissue damage and lower egg densities in heat-treated individuals, suggesting that increasingly severe marine heatwaves can still threaten temperate coral fitness. These results provide insight into corals' nuanced adaptive capacity across latitudes and biological scales.