Luminous quasars at the redshift frontier z > 7 serve as stringent probes of super-massive black hole (SMBH) formation and they are thought to undergo much of their growth obscured by dense gas and dust in their host galaxies. Fully characterizing the symbiotic evolution of SMBHs and hosts requires rest-frame optical observations that span spatial scales from the broad-line region (BLR) to the interstellar and circumgalactic medium (ISM and CGM). The James Webb Space Telescope (JWST) now provides the necessary spatially resolved spectroscopy to do so. However, the physical conditions that regulate the interplay between SMBHs and their hosts at the highest redshifts, especially the nature of early feedback phases, remain unclear. We present JWST/NIRSpec integral field unit (IFU) observations of J0313-1806 at z = 7.64, the most distant luminous quasar known. From the rest-frame optical spectrum of the unresolved quasar, we derived a black hole mass of M-BH = (1.63 +/- 0.10)& times;10(9) M-circle dot based on H beta lambda 4861 (H beta) and an Eddington rate of lambda = L/L-Edd = 0.80 +/- 0.05, consistent with previous Mg II lambda 2800-based estimates. J0313-1806 exhibits no detectable [O III] lambda lambda 4959, 5007 emission on nuclear scales (3 sigma upper limit equivalent width of [O III] lambda 5007 < 1.42 & Aring;). Most remarkably, we did detect an ionized gas shell extending out to similar to 1.8 kpc traced by H beta emission that also lacks any significant [O III] lambda lambda 4959, 5007, with a 3 sigma upper limit on the [O III] lambda 5007 to H beta flux ratio of log(10)(F([O III])/F(H beta)) = -1.15. Through photoionization modeling, we demonstrate that the extended emission is consistent with a thin, clumpy outflowing shell where [O III] is collisionally de-excited by dense gas. We interpret this structure as a fossil remnant of a recent blowout phase, providing evidence for episodic feedback cycles in one of the earliest quasars. These findings suggest that dense ISM phases may play a crucial role in shaping the spectral properties of quasars across cosmic time.
Ecological traits such as behaviour, physiology and morphology mediate an organism's interaction with its environment, and understanding their joint contribution to reproductive fitness is essential for predicting biological responses to global change. We addressed how urbanization shapes trait-function relationships across natural, suburban or urban areas to advance the functional and mechanistic understanding of ecological processes in changing environments. We investigated how interactions among ecological (urbanization, season) and phenotypic (body mass, personality) traits influence reproductive fitness in female Eurasian red squirrels (Sciurus vulgaris) across a natural-urban gradient in Italy. Using 204 records of 72 female squirrels across 12 sites, we found that body mass, mediating the effect of the spring season, was the main factor affecting the probability to reproduce in female red squirrels. Further, our results suggest a direct effect of urbanization on squirrels' reproduction: The probability of reproducing was higher in natural habitats than in the urban and suburban sites. Female red squirrels in natural sites also engaged more frequently in explorative behaviours than their conspecifics in urban sites, but this did not translate into either direct or significant indirect effects of personality on reproductive success. Finally, body mass of females tended to be slightly higher in urban and suburban than in natural habitats, but this did not result in a higher reproductive rate. While body mass emerged as the dominant predictor of reproduction, its functional role was context-dependent, shaped by seasonality, environmental resource distribution and potentially by altered energetic dynamics in urban environments. In contrast, personality traits varied with habitat but did not mediate reproduction, highlighting how trait expression does not equate to ecological function unless matched with the appropriate environmental context. This work underscores the importance of integrating multiple levels of biological organization, behaviour, body mass, life history and environmental context to understand how global change alters ecological and evolutionary trajectories. As urbanization continues to transform natural habitats, studies that disentangle direct and indirect pathways from phenotype to fitness will be essential not only for predicting wildlife persistence but also for linking individual-level processes to population and community dynamics.Read the free for this article on the Journal blog.
Public markets represent urban places capable of contributing to local economies but also spaces in which tourism sustainability can be compromised by visitor flows. This study explored heterogeneity in resident perceptions of tourism sustainability at the Mercato di Luino, a historic market in Northern Italy, with particular attention to the role of transportation-related issues. Using a sample of 742 residents and market users, we applied latent class analysis to identify distinct groups based on their perceptions of the socio-cultural, economic, and environmental dimensions of the shopping space sustainability. A distinctive feature of the study is the comparison of models in the absence and presence of transportation-related characteristics. Besides finding that residents can be classified into three latent classes segmented in terms of sustainability perceptions, the inclusion of transport-based predictors has strikingly altered class membership probabilities. The results showed that mobility issues experienced in market days can play a crucial role in shaping resident attitudes toward tourism sustainability in public open-air marketplaces, with implications for urban and tourism planning.
Establishing credibility and trustworthiness is essential in Economic Agent-Based Modeling (ABM), where clear epistemic standards cannot be defined a priori. In this paper, we first review the notions of trustworthiness and credibility in modeling. We then introduce a framework that emphasizes the modeler's epistemic responsibility to ensure coherence between modeling purposes, strategies and targets. We examine the challenges in assessing model reliability that arise from the interaction of conceptual, algorithmic and computational constituents, and we propose a meta-analytical approach to enhance model consistency by conceptualizing agent-based simulations as iterated analogies. Our analysis outlines strategies for improving model accessibility and reliability while highlighting the modeler's role in preventing mistargeting and misuse. This research provides a normative basis for justifying the credibility of both idealized and targetless models by promoting transparency and consistency between model design and intended purposes.
Well-differentiated neuroendocrine tumors, grade 3 (NETs G3) of the digestive system are high-grade neuroendocrine neoplasms characterized by well-differentiated neuroendocrine morphology and high proliferative activity. Their molecular identity and therapeutic vulnerabilities remain incompletely defined. We performed a transcriptomic analysis and a comprehensive genomic profiling of 40 cases, including 26 NETs G3, 8 NETs G1/G2, and 6 neuroendocrine carcinomas (NECs). Targeted sequencing assessed alterations at both the DNA and RNA level, and gene expression profiling was conducted using a targeted immune-oncology panel. NETs G3 retained recurrent alterations in chromatin-regulatory genes characteristic of well-differentiated tumors and largely lacked the consistent TP53 and RB1 inactivation typical of NECs. Transcriptomic and genomic analysis demonstrated separation of NECs from NETs, with NETs G3 partially overlapping with NETs G1/G2 supporting a model of molecular relatedness. However, when compared with NETs G1/G2, NETs G3 showed upregulation of extracellular matrix remodeling, metabolic reprogramming, and cytokine signaling pathways. NETs G3 were heterogeneous in terms of number of genomic alterations per case and involved genes. A distinctive genomic feature was the predominance of large-segment copy-number losses, frequently involving chromatin-regulatory regions on chromosomes X and 10. Potentially targetable alterations were detected in up to 25% of NETs G3. Analysis of immune microenvironment supported a poorly inflamed tumor status, with individual cases harboring microsatellite instability or enrichment in tumor-infiltrating lymphocytes potentially amenable to immunotherapy.
