Royal Society Open Science最新文献

We report the sequential hydroformylation of (R)-limonene followed by Morita-Baylis-Hillman (MBH) coupling to give two new MBH adducts derived from methyl acrylate (adduct 1, 32% isolated yield) and acrylonitrile (adduct 2, 95% isolated yield). The compounds were characterized by ¹H- and ¹³C-NMR, IR spectroscopy and elemental analysis. Biological screening against protozoa, bacteria, fungi and human cell lines revealed modest antiprotozoal and antimicrobial activity, and the ester adduct (adduct 1) showed the most promising antiproliferative activity (CC₅₀ values: HT-29 = 211.4 ± 49.1 μg ml^-1; PC-3 = 48.0 ± 2.6 μg ml^-1; HeLa = 37.9 ± 6.7 μg ml^-1; HACAT = 53.3 ± 3.1 μg ml^-1). These results introduce a new set of terpene-derived MBH adducts with preliminary antitumoural potential and encourage further optimization and mechanistic studies.

Fledging represents a key life-history transition involving a rapid increase in workload associated with a rapid transition from sedentary nestling to volant, active fledgling. Here, we tested the idea that chicks might prepare for fledging through increased voluntary activity ('exercise') and whether this would impact somatic and physiological development. European starling (Sturnus vulgaris) chicks, in cavity nests, increased levels of putative exercise (wing flapping), and more general active behaviours (e.g. perching, standing) in the five days up to fledging. However, facultative mass loss and wing growth between days 15 and 20 were independent of time spent wing flapping, standing or perching and, counterintuitively, we found a weak negative relationship between haematocrit (a measure of aerobic capacity) and time spent wing flapping or standing. Thus, although exercise is commonly associated with an increase in haematocrit in other species, this does not appear to be a mechanism for increasing pre-fledging haematocrit in chicks. Despite widespread anecdotal observations of flight preparation (e.g. wing flapping) in larger seabirds and raptors, our data suggest that exercise, or increased activity in general, does not contribute to improved development just prior to fledging: starling chicks do not 'exercise' enough to show somatic or physiological effects.

The impact of human behaviour evolution poses a major challenge in the control of COVID-19. The key to overcoming this problem is incorporating behavioural factors into disease interventions. This paper proposes a novel behavioural modulation means based on network intervention strategies, aiming to achieve disease prevention at the population level through behavioural modulation of seed nodes. Taking individual decision-making behaviour as a representative example, we explore the efficacy of the proposed behavioural modulation method within a coupled behaviour-disease model. Using epidemic threshold and infection density as indicators, the results demonstrate that behavioural modulation under various network intervention strategies can effectively control disease transmission within populations. On this basis, the intervention costs incurred by implementing behavioural modulation are also noteworthy. Further analysis reveals an optimal interval of intervention proportions capable of simultaneously achieving epidemic control and cost savings, which can guide the practical implementation of such control measures. The above conclusions are validated through simulation with representative real-world contact network data. Our work has led to new advances in realizing disease control from a behavioural perspective, which is of great value as a guide for the public health sector in the development of epidemic prevention policies.

During the COVID-19 pandemic, the World Health Organization updated guidelines for travel measure implementation to recommend consideration of a region's specific epidemiological, health system and socioeconomic context. As such, travel measure implementation decisions require region-specific data, analysis and models to support risk assessment frameworks. From May 2020 to May 2021, the Canadian province of Newfoundland and Labrador (NL) implemented travel measures that required self-isolation and testing of individuals returning from out-of-province travel. We found that during the pandemic travel to NL decreased by 82%. Our best model was 135 times more likely to explain reported travel-related cases arriving in NL than a model where travel volume and infection data did not consider the Canadian jurisdiction of origin. To test an approach used in other studies, we formulated a model without considering the travel-related case data and found that this model performed very poorly. We conclude that importation models need to be supported with data describing the daily number of travel-related cases arriving in Canadian jurisdictions and daily travel volumes originating from each country and each Canadian province and territory. While there was some reporting of this information during the COVID-19 pandemic, these data were not consistently reported or easily accessible.

This work focuses on the nature of visibility in societies where the behaviours of humans and algorithms influence each other-termed algorithmically infused societies. We propose a quantitative measure of visibility, with implications and applications to an array of disciplines including communication studies, political science, marketing, technology design and social media analytics. The measure captures the basic attributes of the visibility of a given topic in algorithm-mediated communication settings associated, for example, with social media. These attributes are: (i) the amount of time a topic spends at different ranks and (ii) the different ranks the topic attains. In addition, the proposed measure incorporates a tunable parameter, termed the discrimination level, whose value determines the relative weights of the two attributes that contribute to visibility. The proposed measure is applied to the Hot Search List of the Chinese microblog Sina Weibo. Analysis of a large-scale, real-time dataset of topics of this list demonstrates that the proposed measure can explain a large share of the variability of the accumulated views of a topic.

Unlike specialist browsers and grazers, the diets of mixed-feeding megaherbivores are broad and complex, comprising numerous plant species of variable nutritional quality. Understanding key axes of nutritional variation in the diets of mixed-feeding megaherbivores is challenging but is crucial to understand their impacts on vegetation. Here, we revisit a long-standing debate on whether browse is more nutritious than grasses for elephants, as browse is thought to contain higher crude protein (CP). We quantified diet composition using carbon isotope analyses and analysed forage quality in 102 Asian elephant faecal samples from southern India, and found that high-browsing and low-browsing diets had similar forage quality, as indexed by nitrogen and carbon-to-nitrogen ratio. To explore the generality of this finding, we analysed nutritional differences between browse and grass across 141 plant species consumed by Asian elephants across their distribution range. We show that woody tissues and non-legume plants, which dominate elephant browse, do not have higher forage quality or CP than grasses, a trend which may be common in Asia's mixed-feeding large herbivores. Finally, based on the observed habitat-wide variation in browsing, we provide a new framework to assess the impacts of Asian elephants on woody vegetation, with important implications for carbon cycling.

Sleep is an important but overlooked component of animal behaviour, especially its social and conservation facets. Here, we use 15 years of data to comprehensively describe the roosting behaviour of cooperatively breeding birds and test hypotheses about its ecological and social determinants. We show that wild Arabian babbler groups in the Arava Desert of Israel preferred roosting in live plants with dense canopies (mostly Acacia tree spp. and reed clusters). Roosting sites were located in the inner areas of territories regardless of territorial conflicts. Groups almost always roosted in intimate huddles but tended to separate into sub-groups that roost in nearby trees as group size increased. Despite the abundance of suitable sites for roosting, each group only used an average of 2.4 main roosting sites within its territory. Social groups thus exhibited strong, non-random fidelity to specific roosting sites that extended over ≥4 group generations and ≥15 years. To the best of our knowledge, this is the longest roosting site fidelity shown for cooperatively breeding birds and mammals. This study stresses the importance of conserving roosting sites of species with strong site fidelity and lays the foundations for advanced sleep research in a highly cooperative species.

Moral behaviour varies across contexts, yet the influence of the recipient's social status-the person towards whom the behaviour is directed-remains largely underexplored. The strategies used to achieve status can vary substantially and play a crucial role in shaping social perception and behaviour. For instance, dominance-based status triggers negative evaluations, whereas people who attain status through competence or virtue often gain respect and admiration. This preregistered study (n = 151) investigated how an opponent's social status (high, middle or low) and the strategies used to achieve it (dominance, competence or virtue) influenced participants' tendency to lie for self-gain during a card game. Results indicate that participants were significantly less likely to lie for self-gain to virtuous high-status opponents compared to dominant or competent ones. Dominance-based high-status opponents elicited negative emotions (e.g. anger, disgust), while virtuous and competent opponents inspired admiration and respect. These findings highlight that moral behaviour is shaped by both the status of the recipient and the means by which it was acquired, with honesty more likely directed towards virtuous high-status individuals. This research has implications for education and leadership, suggesting that strategies involving virtuous and prosocial behaviours can protect leaders from being deceived by their followership.

Cognitive development can be considered a future-oriented investment that involves life-history (LH) trade-offs, which may be compromised in adverse environments. This study examined how cognitive functioning is related to individual-level environmental deprivation and threat, and the moderating role of demographic LH traits (indexed as adolescent fertility rate, AFR). Using data from the Multiple Indicator Cluster Survey and Global Burden of Disease database, a multi-level structural equation model tested cross-level moderation of AFR on the impacts of deprivation and threat on cognitive functioning (n = 63 861 children and adolescents across 38 countries). Deprivation, rather than threat, was negatively associated with cognitive functioning after adjusting for age, sex, education, maternal/carer's education and gross domestic product. High AFR amplified the negative association between deprivation and cognitive functioning. The findings support that cognitive development may respond to environmental cues of deprivation, and the observed association was further modified by social-level fast LH traits.

Nasonia is a species complex of four parasitoid wasps. N. vitripennis is cosmopolitan, while the other three species are micro-sympatric with it. This distribution can select distinct species-specific mate recognition capabilities. However, whether Nasonia males can distinguish between hosts with conspecific females and those with heterospecific females is not known. Therefore, we test this hypothesis in a cafeteria-based choice assay and show that N. vitripennis males can distinguish hosts with conspecific wasps against those parasitized by N. giraulti and N. oneida, exhibiting longer search time and distance traversed with faster search speed. We also found that N. longicornis males can distinguish hosts with conspecific wasps, but only against the hosts parasitized by N. oneida. We further investigated the pairwise differences in the cuticular hydrocarbon (CHC) profiles of the parasitized hosts and adult female wasps. The results reveal that males show this ability only when the compounds responsible for differences in adult female CHC profiles are also the key differentiators of the host CHC profiles. The comparative mate searching behaviour of males of all reported species within a genus has rarely been studied. Therefore, this study makes a significant contribution to our understanding of interspecific variation of conspecific-mate searching behaviour.