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Distance measurements from the internal dynamics of globular clusters: Application to the Sombrero galaxy (M 104)
Get PDFGlobular clusters (GCs) are dense star clusters found in all massive galaxies. Recent work has established that they follow a tight relation between their internal stellar velocity dispersion and luminosity, enabling accurate distance measurements. In this work, we aim to apply this GC velocity dispersion (GCVD) distance method to measure the distance to M104 (NGC 4594, the Sombrero galaxy). We have measured internal stellar velocity dispersions for 85 globular clusters (GCs) and one ultra-compact dwarf galaxy around M104 using high-resolution multi-object integrated-light spectroscopy with FLAMES/GIRAFFE on the Very Large Telescope. The measured velocity dispersions range from km s , with a mean uncertainty of km s . For a subset of 77 GCs with -band magnitudes and reliable velocity dispersion measurements above km s , we constructed the - relation to measure the distance to M104, finding (stat.)~ (sys.) Mpc. The GCs follow the Milky Way and M31 relation closely, with the exception of the luminous ultra-compact dwarf SUCD1, which is nearly one magnitude brighter than the mean relation. 29 GCs in the sample have sizes determined from Hubble Space Telescope imaging which allowed us to determine their masses and -band dynamical mass-to-light ratios (M/L ). We find a mean for the luminous ( mag) M 104 GCs, which is higher than the Milky Way GCs, but is reminiscent of the brightest GCs in Centaurus A. With the exception of SUCD1, the GCs of M104 follow the GCVD relation irrespective of their mass-to-light ratio
Fixed and Fluid: The Two Faces of Gender Roles—A Combined Study of Activity Patterns and Burial Practices in the European Neolithic
Get PDFObjectives: This study investigates gender roles in the European Neolithic by analyzing activity‐related skeletal changes (ARSCs) and burial practices at two Polgár microregion sites in Hungary: Polgár‐Ferenci‐hát (5300–5070 cal. bce) and Polgár‐Csőszhalom (4800–4650 cal. bce). Materials and Methods: A total of 125 well‐preserved adult skeletons were included in the study. Types of ARSCs examined include spondylolysis (overall workload), humeral enthesopathies (unilateral upper‐limb overuse), and metatarsal facets (habitual postures). Burial positions and grave goods were analyzed to assess sex‐based differences in burial practices. Results: Polgár‐Ferenci‐hát exhibited no clear differences in burial treatment between the sexes, while Polgár‐Csőszhalom displayed marked sex‐related distinctions in burial practices. Individuals at Polgár‐Csőszhalom bore greater physical workloads than those at Polgár‐Ferenci‐hát, though no consistent sex‐based differences in lesions emerged. Males at both sites demonstrated recurrent right upper limb overuse, aligning with broader prehistoric European trends. At Polgár‐Csőszhalom, nine males and one female buried with male‐associated items also exhibited metatarsal facets, linking sex‐associated activity, posture, and social identity. Discussion: The findings suggest that society at Csőszhalom was structured around gendered roles, yet allowed for individual variation. While the limited number of individuals and the inherent uncertainty in interpreting activity markers call for caution, this study enhances our understanding of prehistoric social organization by revealing both recurring sex‐related patterns of behavior and local flexibility in the expression of gender roles
On the moduli space of multi-fractional instantons on the twisted T 4
Get PDFThe moduli space of self-dual SU(N) Yang-Mills instantons on T4 of topological charge Q = r/N, 1 ≤ r ≤ N − 1, is of current interest, yet is not fully understood. In this paper, starting from ’t Hooft’s constant field strength (F) instantons, the only known exact solutions on T4, we explore the moduli space via analytical and lattice tools. These solutions are characterized by two positive integers k, ℓ, k + ℓ = N, and are self-dual for T4 sides Lμ tuned to kL1L2 = rℓL3L4. For gcd(k, r) = r, we show, analytically and numerically (for N = 3) that the constant-F solutions are the only self-dual solutions on the tuned T4, with 4r holonomy moduli. In contrast, when gcd(k, r) ≠ r, we argue that the self-dual constant-F solutions acquire, in addition to the 4gcd(k, r) holonomies, 4r − 4gcd(k, r) extra moduli, whose turning on makes the field strength nonabelian and non-constant. Thus, for gcd(k, r) ≠ r, ’t Hooft’s constant-F solutions are a measure-zero subset of the moduli space on the tuned T4, a fact explaining a puzzle encountered in [1]. We also show that, for r = k = 2, N = 3, the agreement between the approximate analytic solutions on the slightly detuned T4 and the Q = 2/3 self-dual configurations obtained by minimizing the lattice action is remarkable
Boundary Vector Cells Encode a Future-Biased Spectrum of Positions in the Rat.
Get PDFSpatial tuning is a hallmark property of neural firing in the hippocampal formation. Yet, that tuning is often less well correlated with the instantaneous current position of an animal than it is with an integrated version of the past or future state of the animal. Whether that encoding is biased towards past or future states and the extent to which it shows fixed versus multi-scale encoding varies across circuits and cell types. The temporal encoding properties of boundary vector cells of the subiculum are not well established. To address this here, we re-analyzed recordings of BVCs described previously by Lever et al. (2009) with multiple approaches. In the first, we asked if adding a temporal offset between the rat position and the spiking of a BVC increased the apparent spatial tuning in the firing rate map. We found that aligning BVC spiking with future states maximized the rate map spatial tuning. These results were mirrored in a second analysis that, instead of optimizing rate map spatial tuning, optimized how well the firing rate map predicted the BVC spiking. The second analysis also allowed us to ask whether that encoding is focused on a particular temporal horizon or whether the encoding captures behavior at multiple scales. To this end, for a given recording, we asked "How much time-integration of the behavioral state is the observed spiking most consistent with?" We observed a wide spectrum of time-constants of integration across cells, indicating that BVCs form a multiscale encoding of future states. The distribution of both offsets and integration rates observed across BVCs did not differ significantly from other, non-BVC, subiculum neurons. Taken together, these findings indicate that BVCs, along with other subiculum neurons, form a multi-scale encoding of future states
Dancer conversion driven by affective atmospheres: Identity mediation in square dancers’ extreme practices
Get PDFDespite multidisciplinary interest in collective leisure, the formation of intensely dedicated participation remains underexplored. Prevailing studies predominantly attribute leisure devotion to individual motivations or collective functionalities, overlooking the relational mechanism between affective atmospheres and identity transformation in driving compulsive participation. Investigating China's Yaohuoche square dance via theories-in-use, we conceptualize extreme commitment as dancer conversion: a behavioral complex characterized by extraordinary participation, ritualistic attachment, and quasi-religious devotion. We demonstrate that atmospheres (co-produced by bodies, objects, space, technologies, and events) can catalyze dancer conversion through the mediation of triple identity reinvention (self/group/place). By theorizing this “atmosphere-identity-conversion” mechanism, this study advances a relational framework for understanding behavioral extremes in contemporary leisure practices, with implications for understanding identity transformation through ritualized practice, the assemblage of affective spatiality, and micro-politics in everyday life
Centralization, Risk, and Innovation: A Two-Axis Framework for China’s Generative AI Governance in Comparative Perspective
No full textThis article analyses China’s emerging framework for the governance of generative artificial intelligence (AI), placing it in comparative perspective with the United States (U.S.) and the European Union (EU). Drawing on original two-year data of 801 algorithm and generative AI filings (August 2023 to August 2025), it demonstrates how China has developed a centralized, state-first model, built on mandatory national filings supplemented by derivative local registrations. This arrangement enables the state to mobilize resources, counter local protectionism, and endorse national champions such as Baidu, Tencent and DeepSeek. Yet the expansive definition of “high-risk” systems—anchored in “public opinion attributes” and “social mobilization capabilities”—produces an absence of effective risk differentiation, subjecting nearly all public-facing AI services to stringent filing and content moderation. By contrast, the U.S. relies on a decentralized, innovation-first model rooted in federalism and market dynamism, while the EU adopts a hybrid but risk-first approach under the 2024 AI Act. The comparative analysis shows that China’s centralized system has proved effective in the short term for industrial policy and global competitiveness, but risks long-term constraints on innovation. The article reconceptualizes AI governance as a two-axis design space—centralization versus decentralization, and innovation promotion versus risk prevention—and argues that proportionate, transparent, and differentiated regulation is essential for sustainable governance of generative AI
A celatus method for the efficient solution of linear elastic problems with re-entrant corner singularities
No full textThis paper presents an enrichment method for the case of re-entrant corner singularities in linear elastic problems but with no enrichment of the finite element solution space. Instead an a posteriori error estimator, with gradient descent, is used to determine the approximate solution of the coefficients for the enrichment functions about each re-entrant corner. The method then approximately removes the singularities from the problem, increasing its regularity. As a result is that exponential convergence of the error can be achieved with uniform refinement in polynomial order. Almost no improvement in the error is expected or observed if uniform refinement in p is used. The approach is termed the Celatus method as the singularities are hidden from view. As problems are made regular it is shown that exponential convergence rates are observed when the Celatus method is combined with hp-adaptivity (hp-Celatus), requiring far fewer degrees of freedom compared, by orders of magnitude, to traditional finite element analysis with hp-adaptivity. Furthermore each term for the enrichment functions for every re-entrant corner can be evaluated independently. Therefore the method can be implemented in an inherently parallel way. The proposed approach offers an ~10 times reduction in computation time for the same accuracy compared to standard finite element analysis with hp-adaptivity. Additionally, since the solution space is not enriched and is always polynomial, the issue of having near singular matrices does not exist for the Celatus method. The discontinuous Galerkin finite element method is used here, but all equations and methodology are equally applicable to the continuous Galerkin method
Women Are Slightly More Sexually Satisfied in Their Romantic Relationships Than Men: An Integrative Data Analytic Approach.
No full textSexual satisfaction is a common goal within romantic relationships that contributes to individual and relational well-being. Yet, theoretical perspectives, and even popular assumptions, suggest that women may be less sexually satisfied than men. We tested this possibility among people in romantic relationships with two high-powered Integrative Data Analyses (one cross-sectional, n = 11,841, k = 28; one daily-experience, n = 1,827, k = 8, daily reports = 18,321). Contrary to theoretical and lay perspectives, partnered women reported slightly greater sexual satisfaction than did partnered men (r = .08).. To further explore why partnered women reported greater sexual satisfaction than did partnered men, we conducted supplemental analyses that revealed that women's greater sexual satisfaction was not a result of engaging in less frequent sexual behavior, their broader satisfaction with their relationship, or considering partners' sexual enjoyment. In sum, although women may face obstacles that hinder their sexual experiences, these findings suggest that partnered women do not report being less satisfied and instead report being slightly more satisfied with their sex lives than do partnered men. Nevertheless, it is still unknown whether these slight differences in sexual satisfaction have practical implications for couples' relationships or well-being. [Abstract copyright: © 2026. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.
Distinct Crustal Structure Across the Alpine Fault, New Zealand: Seismic Imaging of a Through‐Going Vertical Fault Beneath Its Central Section
Get PDFPlain Language Summary: Constraining fault geometry is key for understanding fault motion and better constraining future rupture scenarios. The Alpine Fault in Aotearoa New Zealand is a major plate boundary strike‐slip fault, that has hosted great earthquakes in the past and is forecast to have a high chance of hosting an earthquake of magnitude 7 or greater in the next 50 years. In this work, we use data from an array of seismometers deployed along the Alpine Fault. We use distant earthquakes recorded at our seismometers to image the subsurface structure around the fault, with a technique called receiver function analysis. We focus on an area where the fault is thought to transition between a vertical geometry to a dipping geometry, which has been a rupture boundary in past earthquakes. Our results indicate that the southern vertical fault section continues to the north past the segment boundary, and that both a vertical and dipping fault may co‐exist beyond the segment boundary
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