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ADF22-WEB: ALMA and JWST (Sub)kiloparsec-scale Views of Dusty Star-forming Galaxies in a z ≈ 3 Protocluster
Get PDFWe present a morphological analysis of Atacama Large Millimeter/submillimeter Array (ALMA) and James Webb Space Telescope (JWST) NIRCam images of nine dusty star-forming galaxies (DSFGs) at zspec ≈ 3.09, all embedded within the cosmic web filaments at the SSA22 protocluster core. The ALMA 870 μm and 1.1 mm images are obtained at spatial resolutions ranging from 0.5″ to 0.05″ (350 pc at z = 3.09). The high-resolution images enable us to resolve inner structures traced by dust continuum, identifying compact dusty cores, clumps, and offset ridges within bars. Sérsic profile fitting was performed for both ALMA 870 μm and NIRCam F444W images at comparable resolutions (∼0.15″). The Sérsic index measured for 870 μm, masking bright regions, indicates values close to unity, suggesting that dust emission arises from disks with superimposed compact core components. For the JWST F444W images (restframe ∼1 μm), the Sérsic indices range between nF444W ∼ 1–3, pointing to the coexistence of bulges and stellar disks in these DSFGs. A comparison of dust mass surface density, nF444W, and F200W–F444W color (restframe ∼0.5–1μm) reveals diversity among the DSFGs, likely reflecting different evolutionary stages, including some DSFGs with red cores, indicating ongoing rapid bulge growth phases heavily obscured by dust. The predominantly disklike morphologies observed in most DSFGs in the protocluster core contrast sharply with early-type morphologies that dominate the highest density environment in the local Universe. This suggests that we are witnessing the early formation of the morphology-density relation, as massive galaxies undergo rapid growth as late-type galaxies fueled by cosmic web gas filaments
Friendships are more group-oriented in the United Kingdom than in Japan
Get PDFFriendship is a common and complex social bond. Among friendship practices yet to be fully understood are group- versus dyadic-oriented friendship styles, or whether people socialize with one versus multiple friends at a time. We report two studies comparing friendship styles and relational mobility among 1674 young adults (18?35?years old) in Japan and the United Kingdom. Respondents from both countries completed the Friendship Habits Questionnaire, a new measure of dyadic- versus group-oriented friendship styles. Participants also estimated their friendship group size and time spent in friendship groups versus dyads, and completed a scale of relational mobility. Participants' group-oriented friendship style, assessed with the Friendship Habits Questionnaire, was associated with larger friendship groups and more time spent in groups, rather than dyads of friends. Compared to Japanese, participants from the United Kingdom had more group-oriented friendship styles and were more relationally mobile. Moreover, group-oriented friendship styles were associated with higher relational mobility. These findings provide insights into models of friendship and social relationships promoted across diverse cultural settings
The Ford Foundation and the development of international relations in China
No full textCurrent explanations of Sino-American relations are dominated by realist and liberal understandings of world politics, neglecting crucial transnational actors that complexify Sino-American relations. In contrast and drawing from internationally-informed Gramscian hegemony theory, and on extensive archival work, we offer an alternative complex multidimensional transnational account. By researching the Ford Foundation’s activities in China and the United States, specifically its contribution to the development of the International Relations (IR) discipline in China, we break new ground and show that Ford was key in profoundly shaping Sino-American relations especially by developing transnational knowledge networks. These transnational elite networks simultaneously integrated China into the LIO and had unintended consequences, particularly in encouraging Chinese counter-hegemonic dynamics that challenge the LIO from within. Our approach indicates the richer complexity of Sino-US relations than extant theories, suggesting that the future trajectories of this strategic relationship are uncertain and do not fall neatly into an inevitable war or peaceful interdependence binary
Measurement invariance and differential item functioning of the Functionality Appreciation Scale (FAS) in five latin american nations
Get PDFThe Functionality Appreciation Scale (FAS) is increasingly used within diverse national and linguistic contexts, but assessments of its functioning across groups remains limited. To extend knowledge, we examined measurement invariance of the FAS across five Latin American nations (Argentina, Chile, Colombia, Mexico, Uruguay), with 1861 respondents. We also assessed differential item functioning (DIF) across respondent characteristics, as well as associations between functionality appreciation and life satisfaction. Confirmatory factor analysis supported a unidimensional structure of the FAS in all national groups, but constraints on a small number of intercepts and uniquenesses had to be relaxed to achieve partial invariance. Likewise, respondent gender, age, and body mass index (BMI) differentially affected some item functioning across national groups, but relaxing constraints on non-invariant paths allowed us to achieve partial DIF. There were no differences in latent functionality appreciation across nations, while men, older participants, and those with lower BMIs had higher functionality appreciation in all national groups. Finally, greater functionality appreciation was robustly associated with higher life satisfaction, with the association being invariant across nations. Further research should assess reasons for non-invariance of some items of the FAS in Latin America, ideally through the use of follow-up qualitative research
Mercury treatment in late medieval European leprosaria? New data from human dental calculus
Get PDFThis study investigates the potential use of mercury-based treatments for leprosy during the late medieval period through the analysis of mercury concentrations in human dental calculus. Calculus samples were obtained from individuals buried at St Leonard's (Peterborough, England) and St Thomas's (Aizier, France) leprosaria, with comparative samples collected from non-leprosaria burial sites where individuals showed no osteological evidence of leprosy. Mercury levels were measured in soil (N = 45) from the burial grounds using atomic absorption spectrometry and in dental calculus (N = 76) using cold vapour fluorescence adsorption spectroscopy. The findings reveal significant variability in mercury concentrations within and between sites, with the dental calculus values ranging from 0.11 to 9.7 mg kg−1. Notably, individuals from leprosaria cemeteries exhibited significantly higher mercury concentrations in their calculus than those from non-leprosaria cemeteries (t(70) = 3.22, p = 0.002). Although mercury levels in the burial soils associated with the individuals sampled in leprosaria cemeteries were elevated compared to the natural geochemical background, the analysis suggests that contamination is probably due to mercury accumulated in soft tissues during life, which could substantially increase the surrounding soil's mercury content during decomposition. Thus, contamination from the surrounding soil was ruled out as the source of mercury in the dental calculus. Integrated with historical and archaeological evidence, these findings may suggest the intentional use of mercury-based treatments for leprosy. This study highlights the role of bioarchaeology in uncovering medieval therapeutic practices and provides the first evidence of mercury linked to medical treatment detected in dental calculus
Hierarchical Multi-Agent Deep Reinforcement Learning for Cooperative Exploration of UAV Swarms
No full textAutonomous exploration of unknown, cluttered environments using unmanned aerial vehicle swarms is critical for applications like search and rescue, yet poses significant challenges in coordination, scalability, and adaptability. Classical methods often struggle with dynamic conditions and large swarm sizes, while standard Multi-Agent Reinforcement Learning (MARL) faces issues like state-space explosion and non-stationarity. This work proposes a novel hierarchical MARL framework to address these limitations. This approach integrates hierarchical grid decomposition for high-level strategic task allocation with multi-agent soft actor-critic for low-level reactive control, enabling efficient navigation and collision avoidance. Training employs a centralised training decentralised execution paradigm to foster cooperation while maintaining decentralised operation suitable for real-world constraints. Results demonstrate that the hierarchical learning approach significantly outperforms a non-learning heuristic baseline in exploration efficiency and exhibits robust scalability with increasing agent numbers
Rewired gene interactions during evolution of the analia and genitalia in Drosophila
No full textDrosophila ventral appendages are considered to be serially homologous structures derived from a ventral appendage ‘ground state’ and shaped by different Hox inputs. The male and female terminalia (analia and genitalia) are highly derived ventral structures defined by Abdominal- B and the sex-determination pathway. In the legs and antennae, a combination of the transcription factors (TFs) C15, LIM1 homeobox 1 (Lim1) and Aristaless (Al) is required for tarsal claw and arista development, respectively. However, the roles of these TFs in terminalia development remained unexplored. We investigated the expression and function of C15, Lim1 and Al during male and female terminalia development. We found that C15 plays distinct roles in males and females, repressing male clasper bristles while promoting bristles on the female epiproct. Contrasting with antennae and legs, C15, Lim1 and Al are not all simultaneously co-expressed in any terminal structure in either sex, indicating interactions among these factors differ across these appendages. Nevertheless, we inferred interactions between C15 and other factors reflecting similarities between leg and male clasper development. Finally, we identified a male-specific C15 enhancer active in male claspers but not in the female epiproct, legs or antennae. This C15 enhancer modularity may underpin tissue- and sex-specific regulatorylogic
Petrologic reconstruction of sulfur transfer processes during mafic magma recharge: Insight from anhydrite-bearing mafic microgranular enclaves
Get PDFIn arc settings, substantial amounts of S are released during volcanic eruptions or sequestered in magmatic–hydrothermal ore deposits, yet the associated silicic melts generally appear S poor. Although mafic magma recharge is considered a major additional S source, the mechanisms by which S is efficiently transferred from recharging mafic magmas into overlying silicic systems remain poorly understood. To address this mechanistic gap, we conducted a detailed petrographic study of anhydrite-bearing mafic microgranular enclaves (MMEs) from the subduction-related Yangxin pluton in the Middle-Lower Yangtze River Metallogenic Belt, China. Two types of plagioclase and amphibole crystals in the MMEs are identified based on textural and compositional characteristics, respectively. PlA and AmpA exhibit reverse core–mantle–rim zonings (An = 24–50 to 61–81 to 20–46 and Al2O3 = 6.8–7.4 wt% to 8.7–9.6 wt% to 6.7–7.8 wt%, respectively) with patchy cores in both crystals and sieve textures in PlA, whereas PlB and AmpB display normal core–rim zonings (An = 60–79 to 28–43 and Al2O3 = 9.3–12.0 wt% to 6.0–8.7 wt%, respectively). Integrating mineral disequilibrium textures, geochemical data, and inferred amphibole equilibrium melt compositions, we propose that the MMEs originated through mingling between the host Yangxin granodioritic magma (characterized by sodic PlA cores and low-Al AmpA cores) and a recharging, oxidized mafic magma (entraining high-Al AmpB cores). This mingling occurred within a hybrid boundary layer along the mafic–silicic interface and proceeded in two stages: (1) in the early-stage, mixed melts with more affinity to the recharging magma crystallized calcic PlA mantles, calcic PlB cores, and medium-Al AmpA mantles; (2) in the late-stage, progressive mingling with the overlying granodioritic magma increased the silicic affinity of the mixed melt, resulting in the development of sodic rims of PlA and PlB, and low-Al rims of AmpA and AmpB.Apatite inclusion S–F–Cl and inferred OH variations in the early‐stage assemblage probably record crystallization‐induced melt S enrichment under fluid‐undersaturated conditions. The exclusive occurrence of primary anhydrite inclusions in the late-stage assemblage indicates that anhydrite saturation was achieved during this interval. Late-stage apatite inclusions likely document a transition from fluid-undersaturated to fluid-saturated conditions, with anhydrite saturation preceding fluid saturation. During aqueous fluid exsolution, crystallized anhydrite would decompose to buffer melt S at anhydrite solubility value for the given melt composition and temperature. Accordingly, the S would continuously be transferred from crystallized anhydrite into the exsolving aqueous fluids without altering melt S contents, and the interstitial anhydrite observed in the MMEs may represent the residual phases after partial decomposition. Although these processes most likely occurred near the mafic–silicic interface, crystallization-driven anhydrite and H2O saturation, together with anhydrite–fluid interactions are expected to operate throughout the recharging magma. This fluid-mediated S transfer mechanism during oxidized mafic magma recharge holds potential for addressing the “excess S problem” in arc magmatic systems
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