This study investigates the behavioural and operational dynamics of a night-time demand-responsive transport (DRT) system in the alpine resort of Hakuba, Japan, within a digitally mediated service environment, with particular attention to the temporal and spatial patterns of seasonal tourism. Using a dataset of 5,232 completed trips, the analysis identifies the key drivers of demand intensity in a low-density mountainous context. The findings reveal a dispersed hub configuration, defined here as notable demand concentration at a limited number of functional stops combined with low geographic clustering and scattered local hotspots. This pattern reflects the role of DRT in connecting physically fragmented activity nodes. Moreover, the results highlight a distinct seasonal tourism rhythm: demand is shaped by month-to-month variation within the winter season and short-term temporal persistence, rather than conventional weekday–weekend cycles. The scale of passenger-carrying service delivery provides a baseline for understanding the operational demands of night-time DRT in rural, seasonally intensive tourism settings. The findings from the study suggest that DRT planning in such contexts should move beyond rigid, calendar-based approaches towards seasonally adaptive strategies that account for temporal persistence and spatial fragmentation in tourism-driven mobility systems.
The James Webb Space Telescope has ushered in an era of abundant high-redshift observations of young stellar populations characterized by strong emission lines, motivating us to integrate nebular emission into the new Maraston stellar population model which incorporates the latest Geneva stellar evolutionary tracks for massive stars with rotation. We use the photoionization code CLOUDY to obtain the emergent nebular continuum and line emission for a range of modelling parameters, then compare our results to observations on various emission line diagnostic diagrams. We carry out a detailed comparison with several other models in the literature assuming different input physics, including modified prescriptions for stellar evolution and the inclusion of binary stars, and find close agreement in the H beta, H alpha, [N II]lambda 6583, and [S II]lambda 6716, 6731 luminosities between the models. However, we find significant differences in lines with high ionization energies, such as He II lambda 1640 and [OIII]lambda 5007, due to large variations in the hard ionizing photon production rates. The models differ by a maximum of Delta Q([OIII]lambda 5007) approximate to 10(44) s(-1) M-circle dot(-1) ,where these differences are mostly caused by the assumed stellar rotation and effective temperatures for the Wolf Rayet phase. Interestingly, rotation and uncorrected effective temperatures in our single star population models alone generate [O III ] ionizing photon production rates higher than models including binary stars with ages between 1 to 6 Myr. These differences highlight the dependence of derived properties from SED fitting on the assumed model, as well as the sensitivity of predictions from cosmological simulations.
Recent observations by the James Webb Space Telescope (JWST) have revealed a puzzling population of optically red and compact galaxies with peculiar 'V'-shaped spectra at high redshift, known as 'Little Red Dots' (LRDs). Until now, most spectroscopically confirmed LRDs are found at z>4 and it has been speculated that LRDs are tracing the early stages of black hole evolution. We report an independent rediscovery of a broad-line active galactic nucleus (AGN), SDSS J102530.29+140207.3, at z=0.1, which shows spectral features matching those of LRDs seen in the early Universe, including the V-shaped spectrum, broad Balmer lines (with widths of 1000-2000 km-1), and deep Balmer absorption. We present a new GTC observation of this LRD, which reveals an optical continuum similar to those of G-to-K giant stars including an unambiguous G-band absorption originating from the CH molecule. In addition, this local LRD shows a series of absorption lines potentially related to low-ionization ions or atoms but are deeper than what is observed in empirical stellar templates. We further identify a series of [Fe ii] emission lines indicative of low-ionization gas, which we find also present in a JWST-selected LRD at $z=2.26$. We find small but statistically significant variability in the H alpha of SDSS J102530.29+140207.3 consistent with previous findings. Finally, we report new observations with NuSTAR. We confirm the extreme X-ray weakness of this LRD, which might imply Compton-thick gas obscuration with N-H >10(24 )cm(-2). All evidence suggests SDSS J102530.29+140207.3 has a complex gaseous environment and the strong ionic, atomic, and molecular absorptions are hard to explain with typical stellar and AGN models.
Measuring galaxy rotation curves is critical for inferring the properties of dark-matter haloes in the Lambda cold dark matter (Lambda CDM) paradigm. We present HI rotation curves and mass models for 20 galaxies from the MIGHTEE survey. Using extended H I kinematics, we construct resolved mass models that include stellar, gaseous, and dark-matter components. Stellar masses are derived using 3.6 mu m imaging under fixed mass-to-light ratio (Upsilon(*) = M/L) assumptions and are complemented, for the first time for a H I-selected sample, by spatially resolved M/L, obtained from multiwavelength spectral energy distribution fitting. We examine the ratio of baryonic to observed rotation velocity (V-bar/V-obs) at the characteristic radius R-2.2. Adopting a fixed Upsilon(*) = 0.5M((R))/L-(R) yields a clear dependence of V-2.2 /V-obs on galaxy luminosity, while adopting Upsilon(*) = 0.2M((R))/L-(R) substantially weakens this trend. In contrast, the resolved M/L analysis preserves the luminosity dependence while modifying the stellar contribution on a galaxy-by-galaxy basis, providing a more accurate representation of the underlying relation. We model the dark-matter haloes using Navarro-Frenk-White profiles and find that the different assumptions for a fixed a M/L systematically shift galaxies relative to the theoretical stellar-to-halo mass and baryonic-to-halo mass relations, while the spatially varying M/L yields the closest agreement with theoretical benchmarks within Lambda CDM. We therefore demonstrate that future investigations of the dark matter properties of galaxies using rotation curves need to account for varying M/L across individual galaxy profiles and between galaxies in order to obtain accurate measurements of the dark matter, and therefore test Lambda CDM.
The sound horizon scale rs is a key source of information for measurements of H0 from early-time data, and is therefore a common target of new physics proposed to solve the Hubble tension. We present a sub-2% measurement of the Hubble constant that is independent of this scale, using data from the first data release of the Dark Energy Spectroscopic Instrument (DESI DR1). Building on previous work, we remove dependency on the sound horizon size using a heuristic rescaling procedure at the power spectrum level. A key innovation is the inclusion of uncalibrated (agnostic to rs) post-reconstruction BAO measurements from DESI DR1, as well as using the CMB acoustic scale theta & lowast; as a high-redshift anchor. Uncalibrated type-Ia supernovae are often included as an independent source of ohm m information; here we demonstrate the robustness of our results by additionally considering two supernova-independent alternative datasets. We find somewhat higher values of H0 relative to our previous work: 69.2+1.3-1.4, 70.3+1.4-1.2, and 69.6+1.3-1.8 km s-1 Mpc-1 respectively when including measurements from i) Planck/ACT CMB lensing & times; unWISE galaxies, ii) the DES Year 3 6 & times;2pt analysis, and iii) Planck/ACT CMB lensing + the DES Year 5 supernova analysis. These remarkably consistent constraints achieve better than 2% precision; they are among the most stringent sound horizon-independent measurements from LSS to date, and provide a powerful avenue for probing the origin of the Hubble tension.
