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We present a multiphase study of the star-formation-driven outflow in the Virgo galaxy NGC 4383, combining ALMA CO(2–1) data with deep MeerKAT Hi imaging and MUSE spectroscopy obtained as part of the Multiphase Astrophysics to Unveil the Virgo Environment (MAUVE) program. Our previous work revealed a spectacular ionised outflow, but the effect of the outflow on the cold phase remained unclear. Our analysis shows that potentially outflowing molecular gas is detected only within the inner ∼1 kpc above the disc, where CO clouds exhibit disturbed kinematics and spatial correspondence with the ionisation cone. At larger heights, the CO surface brightness rapidly drops, indicating that the molecular phase contributes little to the mass of outflowing gas. In contrast, the Hi distribution shows plumes a few kiloparsecs above the disc that are aligned with the ionised cone, and complex kinematics suggestive of parts of the atomic phase being entrained in the outflow. However, the extended and warped Hi disc associated with NGC 4383 complicates the unambiguous identification of outflowing atomic gas and, most importantly, the quantification of outflowing mass and loading factor. Independent support for a cold component in the outflow comes from dust extinction features associated with the outflow and coincident with Hi plumes. Despite significant uncertainties in the estimate of the mass of cold gas associated with the outflow, these results suggest that the atomic phase likely dominates the cold outflow above ∼1 kpc. The observed cold gas velocities remain below the velocities of the ionised phase, suggesting that NGC 4383 does not host a large-scale escaping wind but more likely a galactic fountain, in which feedback redistributes material within the halo and regulates ongoing and future star formation.
The Niagara Escarpment in Hamilton, Ontario, presents significant geohazards, such as block failure, threatening human safety and infrastructure. Despite thorough documentation of the stratigraphy exposed along the escarpment, there remains a lack of quantitative assessment of the rock mass characteristics. This study addresses this gap and offers practical approaches to documenting rock mass characteristics by investigating rock strength properties. The Schmidt hammer (SH), a non-destructive tool widely used in geotechnical and geomorphological research, was used to compare the strength values of rock units exposed along the Niagara Escarpment in Hamilton. Systematic field investigations across selected sites used scanline surveys to measure weathering, fracture continuity, groundwater presence and SH values. The SH rebound values were qualitatively compared with those reported in previous literature and align with lithological expectations. Findings indicate that SH values are significantly influenced by both geographic location and geological formation, with a significant interaction effect. Comparative analysis of rock units in the Ancaster Member of the Goat Island Formation, the Gasport Formation and the Irondequoit Formation showed significant differences (p < 0.005) in rock hardness, with mean SH values of 32.8, 42.2 and 49.1, respectively. These findings demonstrate the necessity of integrating stratigraphic and site-specific geological data into hazard mitigation strategies, as rock hardness influences the stability of the escarpment face. The data reported here demonstrate rock strength variation along the Niagara Escarpment and contribute to the modelling and prediction of geohazards, thereby enhancing geohazard management strategies in similar regions.
At scales larger than the forcing scale, some out-of-equilibrium turbulent systems (such as hydrodynamic turbulence, wave turbulence and nonlinear optics) exhibit a state of statistical equilibrium where energy is equipartitioned among large-scale modes, in line with the Rayleigh–Jeans spectrum. Key open questions now pertain to either the emergence, decay, collapse or other non-stationary evolutions from this state. Here, we experimentally investigate the free decay of large-scale hydroelastic turbulent waves, initially in a regime of statistical equilibrium. Using space- and time-resolved measurements, we show that the total energy of these large-scale tensional waves decays as a power law in time. We derive an energy decay law from the theoretical initial equilibrium spectrum and the linear viscous damping, as no net energy flux is carried. Our prediction then shows a good agreement with experimental data over nearly two decades in time, for various initial effective temperatures of the statistical equilibrium state. We further identify the dissipation mechanism and confirm it experimentally. Our approach could be applied to other decaying turbulence systems, with the large scales initially in statistical equilibrium.
The death of chess Grandmaster and content creator Daniel Naroditsky sparked heated debate on the impact of cyberbullying on his mental health in the last 2 years of his life. Cyberbullying remains a widespread public health problem, with strong associations to mental disorders and significant relevance to psychiatric practice worldwide.
We prove under certain conditions that any stable unfolding of a quasi-homogeneous map-germ with finite singularity type is substantial. We then prove that if an equidimensional map-germ is finitely determined, of corank 1, and either it admits a minimal stable unfolding or it is of multiplicity 3, then it admits a substantial unfolding if and only if it is quasi-homogeneous in some coordinate system. Based on this, we pose the following conjecture: a finitely determined map-germ is quasi-homogeneous in some coordinate system if and only if it admits a substantial unfolding.
Newton famously rejected the use of hypotheses in natural philosophy, in stark contrast to many of his contemporaries, such as Descartes, Huygens, and Leibniz, who employed hypothetical methods. This disagreement is often framed as one concerning the Hypothetico-Deductive (HD) method, but I argue that this is mistaken. The relevant hypothesis-based methods at issue were what I call inference to the best hypothesis and its stronger version, inference to the only plausible hypothesis. These methods were far more nuanced and plausible than HD, and they enjoyed widespread popularity among early modern thinkers, even among prominent experimental philosophers. Newton rejected them nonetheless.
The ability of multirotor unmanned aerial vehicles (UAVs) to perform accurately in windy environments is crucial for extended use in outdoor applications. To design UAVs to operate in these environments, most studies have focused on static performance metrics such as thrust-to-weight ratio and endurance, without directly considering closed-loop control performance. This work develops a simplified metric that serves as a predictor for achievable disturbance rejection performance, enabling efficient UAV design selection without requiring full-scale nonlinear simulations. A reduced-order model is introduced to capture key aerodynamic and actuation characteristics, allowing for rapid evaluation of UAV configurations. The metric is validated against high-fidelity nonlinear simulations, demonstrating strong correlation with actual control performance. By bridging the gap between UAV structural optimization and closed-loop control behavior, this approach provides a practical tool for integrating disturbance rejection capabilities into UAV design processes. The practical utility of this metric is supported by experimental findings from related wind tunnel studies of fully-actuated UAVs, which demonstrate that actual disturbance rejection performance aligns with the trends predicted by the simplified correlation function.
The linear instability of liquid film with insoluble surfactants on a quasiperiodic oscillating plane for disturbances with arbitrary wavenumbers is investigated. The combined effects of insoluble surfactants and quasiperiodic oscillation on the instability are described using Floquet theory. For long-wavelength instability, the solution in the limit of long wave perturbations is obtained by the asymptotic expansion method. The results show that a new stable region emerges in the low-frequency domain of the neutral stability curve in the absence of gravity. As the imposed frequency increases, this newly formed stable region is progressively absorbed into a broader stable zone. The U-shaped neutral curves with separation bandwidth appear in the presence of gravity, and the presence of the surfactants will decrease the unstable frequency bandwidth and increase the critical Reynolds number. The finite-wavelength instability is solved numerically based on the Chebyshev spectral collocation method. Both travelling-wave and standing-wave modes are found due to the existence of surface surfactants. As the surfactant concentration increases, the finite-wavelength instability region expands significantly, and the intersection point marking the transition from travelling waves to standing waves shifts progressively towards lower frequencies. The physical mechanisms underlying perturbation growth are further elucidated through an energy budget analysis. Energy budget analysis demonstrates that long-wavelength instability is dominated mainly by surface shear stress, whereas finite-wavelength instability is primarily governed by the combined effects of Reynolds stress and surface shear stress.
Research syntheses have demonstrated that pronunciation instruction works, which means that whether instruction is effective is no longer an open question. Instead, contemporary intervention research has shifted to investigating how instruction can be further optimized, asking targeted questions about the instructional features that catalyze learning. In this paper, I examine the concept of instructional optimization, focusing on anticipated effect sizes (gains). I outline a four-pronged empirical approach to provide robust data for designing optimal pronunciation interventions. First, I describe the need for replication studies, which provide insight into the precision and stability of effects across distinct research samples and contexts. Second, I advocate for a systematic approach to study design. In such an approach, which is closely tied to the principles of replication, one or two variables are manipulated at a time, leading to a set of maximally comparable studies that lend insight into the impact of specific variables. Third, I explain the need to situate instruction within a longitudinal perspective to examine how robust and durable instructional gains are. Finally, I turn to adaptive approaches, where the surface format that instruction takes is highly variable and responsive to learner needs while the adaptive decision tree that generates the form is fixed and replicable.
This is a study of how opposing cultural values influence support for minorities’ civil liberties. We build on a rich body of work, which establishes that culturally liberal Europeans are more likely to value diversity and favor minority rights than are cultural conservatives. Our contribution is to bring attention to how a second dimension of value conflict upends this established pattern. If a religious minority, in this case Muslims, wants to use their religious freedom to call on Muslims to adhere to conservative Islamic values – to preach them – support for their civil liberties plunges. We report substantively large and remarkably consistent results from seven classical tolerance experiments conducted in three European countries. In each trial, we observe the tendency of non-Muslims to deny Muslims their right to freedom of religion. We consistently observe that culturally liberal citizens join cultural conservatives in turning against Muslims’ right to hold a public rally when Muslims intend to exercise their right to freedom of expression to preach (the speech-act dimension) culturally conservative ideas in Islam (the substantive dimension). Preaching is a performative utterance, an instance of when saying something is doing something. What is being done, in addition to what is being said, is to call for compliance. This study finds that conflicts with religiously grounded values in contemporary European liberal democracies often have an additional order of intensity, because stating religious beliefs in the form of performative utterances is an integral part of religious practice.
This paper reports analytical solutions for steadily travelling two-dimensional water waves on deep water, without gravity or surface tension, carrying a cotravelling periodic row of hollow vortices. The solutions are hollow-vortex regularisations of the exact solutions of Crowdy & Roenby (Fluid Dyn. Res., vol. 46, 2014, 031424) for the analogous waves carrying a submerged point-vortex row, the free-surface shapes of which coincide with those for pure capillary waves and, like those, exhibit steady pinchoff at a critical wave amplitude. The same pinchoff phenomenon is shown to occur for the hollow-vortex regularisations. The new wave solutions are likely to provide a useful basis for perturbative, asymptotic or numerical studies when additional effects such as gravity, capillarity or compressibility are incorporated.
Cardiac hydatidosis accounts for less than 2% of Echinococcus granulosus infections. Despite Syria’s high endemicity, paediatric cardiac involvement remains exceptionally rare and underreported. We report two Syrian children (aged 5.5 and 9 years) with giant interventricular septal hydatid cysts. Case 1 presented with significant hemodynamic obstruction, while Case 2 exhibited malignant ventricular arrhythmias. Both underwent successful cardiopulmonary bypass-assisted cystectomy with capitonnage repair and adjuvant albendazole therapy. These cases underscore (1) the life-threatening nature of advanced paediatric cardiac hydatidosis and (2) the critical role of early surgical intervention in endemic regions. Written informed consent for publication was obtained.
To test the ‘Investigate Exposure’ step of the WHO’s CLICK framework, and to investigate 12–16-year-old children’s exposure to paid-for digital food advertising in Finland.
Design:
The DIGITUTKA pilot study was carried out as part of the EU Joint Action Best-ReMap project. Data on paid-for digital food advertising that children were exposed to via their phones over a two-weeks period were captured using the RealityMeter-application, following the ‘Investigate Exposure’ step of the CLICK framework. Data were collected between April and June 2022 and analyzed in Excel, following a protocol outlined by WHO Europe. The WHO Europe Nutrient Profile Model (v1, 2015) was used to determine marketing permission.
Setting:
Four schools in Finland
Participants:
6th-9th grade students (n=34)
Results:
Out of the 17 820 captured advertisements, 2316 (13%) were identified as food or beverage brands and products. The most commonly advertised products were convenience foods, composite dishes (16%, N=372), and energy drinks (9%, N=202). The majority of the food and beverage advertisements (N=1291, 56%) were not permitted to be marketed to children, with only one in ten (N=222, 9%) was permitted to be marketed to children. A third (35%) of the food and beverage advertisements could not be identified due to missing information.
Conclusions:
Children were exposed to a large number of food and beverage advertisements, most of which were not permitted to be marketed to children. To protect children’s health and prevent obesity, marketing restrictions should be combined with broader changes to the food environment and taxation.