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<i>Euclid</i>:An emulator for baryonic effects on the matter bispectrum
No full textThe Euclid mission and other next-generation large-scale structure surveys will enable high-precision measurements of the cosmic matter distribution. Understanding the impact of baryonic processes such as star formation and active galactic nuclei (AGN) feedback on matter clustering is crucial to ensure precise and unbiased cosmological inference. Most theoretical models of baryonic effects to date focus on two-point statistics, neglecting higher-order contributions. This work develops a fast and accurate emulator for baryonic effects on the matter bispectrum, a key non-Gaussian statistic in the nonlinear regime. We employ high-resolution N-body simulations from the BACCO suite and apply a combination of cutting-edge techniques such as cosmology scaling and baryonification to efficiently span a large cosmological and astrophysical parameter space. A deep neural network is trained to emulate baryonic effects on the matter bispectrum measured in simulations, capturing modifications across various scales and redshifts relevant to Euclid. We validate the emulator accuracy and robustness using an analysis of Euclid mock data, employing predictions from the state-of-the-art FLAMINGO hydrodynamical simulations. The emulator reproduces baryonic suppression in the bispectrum to better than 2% for the 68% percentile across most triangle configurations for k ∈ [0.01, 20] h Mpc−1 and ensures consistency between cosmological posteriors inferred from second- and third-order weak lensing statistics. These results demonstrate that our emulator meets the high-precision requirements of the Euclid mission for at least the first data release and provides reliable forecasts of the cosmological information contained in the small-scale matter bispectrum. This underscores the potential of emulation techniques to bridge the gap between complex baryonic physics and observational data, maximising the scientific output of Euclid
The social and environmental impacts on local residents from tourist accommodation near protected areas
No full textTourism is often promoted as a strategy for offsetting the social impacts on the lives and livelihoods of people in nearby host communities from conservation actions and the establishment of protected areas and national parks. However, the presence of tourists also creates significant negative social and environmental impacts on local people and communities. We examine the impacts created by rural tourism operators (specifically boutique rural hotels and bed-and-breakfast enterprises) on the residents of Longweiba village in the Wulingyuan Historic and Scenic Area, Hunan Province, China. The management arrangements for this World Heritage Site mean that residents are regulated by different management regimes depending on whether they are inside or outside the high conservation zone, which has created inequity and conflict. Using an ethnographic approach and interviews with 30 local residents and one government official, our results reveal that, while tourism has contributed to local economic development and improved the living environment, it has also led to a range of concerns about: protected area management; various environmental issues; inequitable regulations; inconsistent governance policies; unfair building restrictions; sewage; odor pollution; water shortages; and a fear of involuntary resettlement. The poor planning of tourism, inequitable policies, and inconsistent enforcement of regulations have exacerbated these issues. We conclude that, while tourism has some benefits for host communities, better governance and environmental management, more inclusive community engagement, and clear consistent policies are needed to ensure that tourism development within or near protected areas is sustainable and equitable.</p
Media influences on ethnic majority attitudes toward ethnic minorities:A systematic review and meta-analysis
No full textThe media are widely regarded as critical in shaping ethnic majority attitudes toward ethnic minorities. Yet despite this presumed influence, the mechanisms underlying this influence remain insufficiently understood. This systematic review and meta-analysis synthesizes existing research, identifying three key empirical pathways through which media are thought to operate: salience (prominence of information about ethnic minorities), valence (ranging from negative to positive evaluations of ethnic minorities), and consumption (the overall volume of media exposure). We further examine moderators specific to valence, namely sign (positive versus negative) and source (evaluation by ethnic majority ingroup or ethnic minority outgroup), as well moderators applying across all three pathways: media type (traditional versus social/online) and format (viewing versus reading). Our meta-analysis encompasses 1587 effect sizes from 155 articles published between 2010 and 2022, representing approximately 350,000 respondents. We find that media salience has a weak positive relationship with negative ethnic majority attitudes toward immigration, but not with attitudes toward ethnic minorities themselves. Media valence shows a weak positive relationship with attitudes, with smaller effects for positive valence on positive attitudes and larger effects for negative valence on negative attitudes. Moreover, valence shows a positive relationship with attitudes when the evaluation originates from ethnic out-groups, but no relationship when it originates from ethnic in-groups. Finally, we find no evidence of a significant relationship between media consumption and attitudes. We conclude by identifying critical gaps in the literature and by advocating for an integrative approach that considers how salience, valence, and consumption interrelate in shaping ethnic majority attitudes toward ethnic minorities.</p
From Fraught Politics to Influencer Ethics:Patriotism, Spirituality, and Survival in Nigerian Creator Cultures
No full textPositive imaginative potential is crucially deficient among Nigerian youth, yet creators commonly perform optimism, confidence, and enjoyment online. The chapter examines the negotiations of this fraught equilibrium, drawing on a year-long in-person ethnography of the Lagos entertainment industry, supplemented by digital ethnography. It shows that Nigerian creator cultures tend to emphasise the achievability of personal success and wilfully ignore social structure – an approach with roots in Pentecostal religion and popularly cast as “spiritual”. The chapter argues that widespread perceptions of the state as incurably passive and predatory frame entrepreneurship and performativity as moral imperatives for psychological and economic survival. Content creators commonly circulate a discourse that postulates the enterprising, commodified, and branded self as a force that can transform its circumstances and contribute to changing Nigeria’s place-in-the-world, even if the benefits often accrue only to a few individuals. The chapter shows that in a context where less than five percent of the population believes that the country is moving in the right direction, Nigerian creator cultures sustain optimism faith in the market and the power of algorithms alongside forms of conscious emotional labour
Integrating Co-Created and Theory-Driven Insights: A Worked Example Using an Equitable and Power Sharing Approach
No full textCo-creation with citizens has emerged as an integral component in tackling a plethora of healthcare inequities. At the stage of scientific conceptualization, processes of integrating co-created insights as legitimate forms of knowledge lack transparent methods, risking disempowerment for citizens who have been positioned as influencing research processes and outcomes. We detail an approach to integrating co-created insights into a scientific model using an equitable and power-sharing approach (EPSA) method, exampled during the study design phase of the AFFIRM Relationships project. The EPSA method consists of three phases: a preparatory phase (researcher reflexivity, topic formulation and sensitization); a co-creation phase (knowledge production, analytic phases, summarizing and ethics work) and an insight integration phase. Applying the EPSA method highlighted the important role of researcher reflexivity in preparing to foster a safe environment for open dialogue during co-creation. Transforming scientific research stages into activities that can engage co-researchers (including conducting analysis, critical thinking, and producing overarching themes) underscored an equitable partnership. While the final phase enabled identification of how resulting knowledge was derived (i.e., via co-creation or existing theory), further consideration of how refinement processes can be grounded in lived experience is necessary, particularly during final stages as decision-making becomes increasingly led by academic team members
Individualized Prediction of Platelet Transfusion Outcomes in Preterm Infants With Severe Thrombocytopenia
No full textIMPORTANCE: Preterm infants with severe thrombocytopenia (platelet count <50 × 109/L) frequently receive platelet transfusions. However, it is unclear in what cases prophylactic transfusion truly reduces bleeding risk or whether it does more harm than good.OBJECTIVE: To develop and validate a dynamic prediction model for major bleeding or mortality if prophylactic platelet transfusion were or were not to be given to infants with severe thrombocytopenia.DESIGN, SETTING, AND PARTICIPANTS: The dynamic prediction model was developed in an international multicenter cohort (2017-2021) comprising 14 neonatal intensive care units in the Netherlands, Sweden, and Germany. Model evaluation was performed in a national multicenter cohort (2010-2014) including 7 Dutch neonatal intensive care units. The study population consisted of infants with severe thrombocytopenia less than 34 weeks' gestation.EXPOSURE: Two transfusion strategies were contrasted at each prediction point: receiving a platelet transfusion within 6 hours (prophylaxis) vs no platelet transfusion for 3 days (no prophylaxis).MAIN OUTCOMES AND MEASURES: The primary outcome was the 3-day risk of major bleeding or mortality, reestimated every 2 hours during the first week after severe thrombocytopenia onset. Predictors included gestational and postnatal age, small-for-gestational-age infant, necrotizing enterocolitis, sepsis, mechanical ventilation, vasoactive agents, platelet count, and prior platelet transfusion(s). Landmarking combined with the clone-censor-weight approach enabled dynamic prediction under the 2 transfusion strategies, accounting for time-varying confounding. Model performance was evaluated in the external validation cohort.RESULTS: In both the development (n = 1042) and validation (n = 637) cohorts, the median gestational age was 28 weeks and median birth weight was 900 g; there were 613 (59%) and 370 (58%) males, respectively. Major bleeding or death occurred in 235 infants (23%) in the development cohort and 135 (21%) in the validation cohort. In the validation cohort, the time-dependent area under the receiver operating characteristic curve was 0.69 (95% CI, 0.60-0.76) for the prophylaxis strategy and 0.85 (95% CI, 0.76-0.92) for the no prophylaxis strategy, with calibration plots showing good calibration. Estimated risks under both strategies varied considerably depending on the infant's clinical condition at the time of prediction.CONCLUSIONS AND RELEVANCE: Among preterm infants with severe thrombocytopenia, this modeling study found substantial variation among individuals in predicted benefits and harms of prophylactic platelet transfusion based on their current clinical characteristics. The dynamic prediction model performed well in a validation cohort, and its value to support individualized decisions warrants evaluation in future studies..</p
Geoarchaeological Investigation of Early Neolithic Lagoonal Fringe Landscapes in the Netherlands
No full textCoastal wetlands have historically been portrayed as too marginal for early crop cultivation during the Mesolithic–Neolithic transition due to their dynamic hydrology, low elevation, and poor drainage. However, growing evidence suggests that these environments played a crucial role in the spread of agriculture. We examined buried and submerged channel–levee systems beneath present-day Lake IJssel (the Netherlands) to investigate the spatial and temporal extent to which wetland levees provided suitable grounds for cultivation as rivers functioned while the sea level rose. The study area lies along the lower reaches of the paleo-Vecht River, one of two local rivers crossing the Swifterbant-type area, with key sites located 10–20 km inland. Integrating sedimentary geology, archaeological soil micromorphology, and radiocarbon dating of research cores, we identify buried soil horizons indicating periods of reduced sedimentation and relatively stable, dry conditions conducive to human activity. Micromorphology reveals charred plant material, ceramic fragments, and disturbed soil aggregates comparable to tilled fields at Swifterbant settlements. Radiocarbon dating places these features between ca. 4500 and 4200 BC, coinciding with upstream occupation. These findings add to growing evidence of widespread, sustained land use in these wetland environments and highlight the value of micromorphology in detecting subtle traces of human activity in landscape-scale studies.</p
Physics meets tradition:An ethnophysics study of the Perahu Jong in developing students' science literacy
No full textThe present study investigates the impact of the Perahu Jong cultural festival on students' cultural literacy and their understanding of physics concepts on Rupat Island, Indonesia. Utilizing a convergent mixed-methods approach, the research combined qualitative data from interviews and observations with quantitative data from a validated survey, involving 109 students from six schools. The instrument validation process included an expert panel and reliability analysis to ensure methodological rigor. The findings indicated that students' understanding of physics concepts related to the festival included Newton's Laws, Waves, Equilibrium, Pressure, Static Fluids, and Dynamic Fluids. Despite a generally low level of cultural literacy, Spearman's correlation analysis revealed a statistically significant. However, the correlation was categorized as weakly positive (rs = .266, p = .005) between cultural literacy and physics conceptual literacy, indicating that cultural understanding is related to academic achievement but explains only a limited proportion of the variance in physics literacy.266, p < .001) between cultural literacy and physics conceptual literacy, underscoring the critical role of cultural understanding in academic achievement. This study makes a unique contribution by quantitatively demonstrating the relationship between cultural literacy and physics conceptual literacy, particularly in coastal communities with strong ties to the Perahu Jong tradition, and presents a validated model for culturally responsive pedagogy.</p
Experimental evidence for large carnivore risk cues reducing deer browsing intensity in a temperate forest
No full textIntensive ungulate browsing represents a major challenge for managing temperate forests, and only a clear understanding of the underlying ecological processes can help to mitigate its impact. Predator–prey interactions play a crucial role in shaping browsing patterns; however, the lack of a comprehensive understanding of these dynamics hinders the development of functional policies. Using an experimental approach, we simulated large-carnivore presence using olfactory cues to examine the effects of predation risk on deer behaviour and its consequences for browsing intensity on tree saplings. We conducted this experiment in 11 locations in the Bavarian Forest National Park (Germany), each comprising four plots with olfactory cues of wolf, lynx, cow and water (control). In each plot, we planted 30 saplings representing the five most common tree species in the area, which we regularly monitored to assess browsing intensity and selectivity. In addition, we set a camera trap at each plot to record deer species (red and roe deer), age, sex and behavioural metrics like time spent vigilant, visitation duration and visitation frequency. This experimental design allowed comparisons of the effects of different large carnivore on prey species while measuring browsing intensity. Our results demonstrated that deer modified their behaviour in response to large carnivore scent cues compared to non-risky cues, with more pronounced effects in lynx treatments compared to controls. Red and roe deer spent significantly less time in lynx treatments compared to controls, especially at dawn and dusk. In spring at dusk, we observed similar decreases in visitation duration in wolf treatments. Notably, our findings also show increased vigilance time of adult deer accompanied by juveniles at sites with lynx cues during winter nights. As a consequence of these behavioural changes, we recorded a significant reduction in browsing intensity in lynx treatments compared to controls. However, no signs of tree species selectivity were found in plots with large carnivores scent cues nor differences in visitation frequency. Synthesis and applications. By analysing multiple behavioural responses and considering relationships between different trophic guilds, we provide unique insights into the mechanisms of predator–prey interactions and their indirect impact on forest ecosystems. In particular, our findings highlight the role of large carnivores in mitigating ungulate browsing damages, which is important for managing temperate forests (both natural and commercial) where herbivore browsing is a significant pressure.</p