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The Cygnus Allscale Survey of Chemistry and Dynamical Environments: CASCADE
No full textContext. Filamentary gas flows are an important process for funneling gas from cloud scales onto star-forming cores.
Aims. We investigate the role of filaments in high-mass star formation, whether gas flows from large to small scales along them, and what their properties might reveal about the region they are found in.
Methods. The Max Planck IRAM Observatory Program (MIOP), the Cygnus Allscale Survey of Chemistry and Dynamical Environments (CASCADE), includes high spatial resolution (~3″) data of HCO+(1–0) and H13CO+(1–0) emission in the star-forming region DR20 in the Cygnus X complex. In this data we identify filaments with the structure identification algorithm DisPerSE. We further analyze these filaments using Gaussian fits to the spectra to determine the line peak velocity and full width half maximum along them. The Python package FilChaP was used to determine filament widths.
Results. We find projected velocity gradients inside several filaments between 0.4 and 2.4 km s−1 over projected length-scales of 0.1 pc toward star-forming cores. This can be interpreted as a sign of gas flowing along the filaments toward the cores. The filament width distributions exhibit median values between 0.06 and 0.14 pc depending on the core, the tracer, and the method. Standard deviations are approximately 0.02 to 0.06 pc. These values are roughly in agreement with the filament width of 0.1 pc typically found in nearby low-mass star-forming regions.
Conclusions. This first analysis of filamentary properties within the Cygnus X CASCADE program reveals potential signatures of gas flows along filaments onto star-forming cores. Furthermore, the characteristics of the filaments in this high-mass star-forming region can be compared to those of filaments in low-mass star-forming regions typically studied before. Extending such studies to the entire CASCADE survey will enhance our knowledge of high-mass filament properties on solid statistical grounds
The Arizona-Montréal Spectroscopic Survey of hot subluminous stars
No full textContext. Hot subdwarf B (sdB) and O (sdO) type stars are evolved helium-burning objects that lost their hydrogen envelope before the helium flash when their progenitors were close to the tip of the red giant branch (RGB). They populate the extreme horizontal branch (EHB) in the Hertzsprung-Russell diagram (HRD). The mass distribution of canonical hot subdwarfs is expected to peak at the core mass required for helium ignition under degenerate conditions in the 0.45-0.5 M⊙ range. However, non-degenerate helium ignition from intermediate-mass progenitors and non-canonical pathways, such as the merger of helium white dwarfs and delayed helium flashes, are also expected to contribute to the hot subdwarf population.
Aims. Using high-quality, homogeneous spectra of 335 hot subluminous star candidates from the Arizona-Montréal Spectroscopic Survey, we aim to improve our understanding of the atmospheric and stellar properties of hot subdwarf stars. Our focus is on the mass distribution of the different types of hot subdwarfs and their connections to the various formation scenarios.
Methods. We used large grids of model atmospheres to fit the observed spectra and derived their atmospheric parameters: effective temperature (Teff), surface gravity, and helium abundance. The model grids were further utilized to fit the spectral energy distribution of each star and the Gaia parallax was used to compute the stellar parameters radius, luminosity, and mass.
Results. Our spectroscopic sample mostly consists of H-rich sdBs and sdOs, but also contains 41 He-rich sdOs. Additionally, the sample includes 11 intermediate-helium stars and 19 horizontal branch objects with Teff > 14 kK. We detected the presence of helium stratification in six sdB stars with Teff around 30 kK, making them good candidates for also showing 3He enrichment in their atmospheres. Our sdB distribution along the EHB shows a gap near 33 kK, visible in both the Kiel (logg-Teff) diagram and HRD, corroborating previous observations and predictions. The mass distributions of H-rich sdBs and sdOs are similar and centered around 0.47 M⊙, consistent with the canonical formation scenario of helium ignition under degenerate conditions. Among the H-rich hot subdwarfs, we found no difference between the mass distributions of close binaries and apparently single stars. The He-sdOs have a significantly wider mass distribution than their H-rich counterparts, with an average mass of about 0.78 M⊙. In the HRD, the He-sdOs lie on the theoretical helium main sequence for masses between 0.6 and 1 M⊙. This strongly favors a merger origin for these He-rich objects. We identified a small number of candidate low-mass (<0.45 M⊙) sdBs located below the EHB that might have originated from more massive progenitors. These low-mass sdBs preferentially show low helium abundances. Finally, we identified more than 80 pulsating stars in our sample and found that they fall into well-defined p- and g-mode instability regions
Regulation Mechanism of p-Akt and lncRNA H19 in Colorectal Cancer
No full textColorectal cancer (CRC) has been a widespread kind of malignant neoplasm worldwide. It has been one of the major contributing reasons for cancer-related deaths globally, with high incidence and mortality; colorectal liver metastases (CRLM) are the main causes of death in CRC patients, and signaling pathway dysregulation-driven abnormal cell proliferation is the core driver of CRC progression. Clarifying the regulatory mechanisms of key molecules in proliferative pathways is critical for developing therapeutic strategies. This study focuses on investigating the abnormal activation of phosphorylated Akt (p-Akt) in the PI3K/Akt pathway during CRC proliferation and the regulatory function of long non-coding RNA (lncRNA) H19. These results show that p-Akt activation in CRC is driven by multiple mechanisms, including overactivation of upstream oncogenic pathways (e.g., HGF/c-Met), abnormal expression of phosphatases (e.g., PRL-3), inactivation of negative regulators (e.g., PTEN), and tumor microenvironment factors (e.g., exosomes). LncRNA H19 is obviously overexpressed in CRC tissues, promoting cell proliferation via ceRNA-mediated mechanisms (e.g., adsorbing miR-200a to upregulate ß -catenin). Notably, H19 regulates p-Akt activation through ceRNA mechanisms to target PI3K/Akt pathway mRNA and protein interactions (e.g., binding to hnRNPA2B1), forming a regulatory network that drives CRC progression. This paper systematically integrates the regulatory relationship between H19 and p-Akt, providing a comprehensive theoretical basis for developing combination-targeted therapies (e.g., H19 siRNA combined with PI3K inhibitors) for CRC
Rescattering-induced
No full textWe investigate two-body non-leptonic weak decays, where S denotes a light scalar meson such as or Short-distance topologies from W-boson emission and annihilation (exchange) are found to be negligible, while long-distance final-state interactions provide the dominant contributions. In particular, triangle rescattering processes, and mediated by pion exchange in and scatterings, respectively, are identified as the leading mechanisms. Our calculations yield branching fractions and For the Cabibbo-allowed decay mode the near-threshold condition limits the phase space, suppressing the branching fraction to These results highlight rescattering-induced decays as promising channels for experimental studies at BESIII, Belle(-II), and LHCb
Domestication and Behavioural Evolution: Convergent and Divergent Outcomes in Dogs and Cats
No full textThe domestication of cats and dogs through symbiotic pathways has introduced them into human space to reduce their fear and reactive attacks, providing them with opportunities to acquire human resources and social connections. For thousands of years, choices in these environments have resulted in convergent and divergent behavioral outcomes. This article combines evidence from behavior, neuroendocrine and genetic mechanisms, development, and contemporary ecology to explain why cats and dogs have similar adaptability to humans but different social motivations. Existing research demonstrates that dogs exhibit significant human centered social cognition, such as using pointing and gaze, as well as seeking help, which is supported by oxytocin related pathways and early socialization. Cats can also form stable attachments, follow human cues, recognize their own names, but they exhibit more context dependent seeking behavior and focus more on reward and fear regulation circuits. The developmental time and contemporary ecological environment further shape the adult phenotype through gene environment interactions. This evidence suggests that attachment ability and sensitivity to human cues are similar, but there are differences in cooperation and group organization. This article reveals how urbanization and management practices utilize the social motivations of specific species to improve welfare, conservation outcomes, and public health
Transient analysis method of aerothermoelasticity based on ARMA model
No full textA novel time-domain method is introduced to address the challenges of aerothermoelastic analysis in the rapidly changing transient thermal environments for hypersonic vehicles. The present method strikes a balance between the computational accuracy and the efficiency. Firstly, the autoregressive moving average (ARMA) model is used to replace the aerodynamic simulations. Subsequently, a time-domain method for aeroelastic analysis is established by coupling the ARMA model and the modal superposition method. Thereafter, the aerodynamic heating is calculated by using the numerical method based on Euler equations in conjunction with the established engineering techniques. The transient thermal field is simulated by using the bidirectional coupling of aerodynamic heating, heat conduction and heat radiation. Finally, based on the hierarchical coupling strategy, an efficient and accurate time-domain method for aerothermoelastic analysis in the transient thermal environment is presented. This method utilizes the structural mode as a connecting hub between aeroelastic analysis and transient thermal field simulation. The performance of the present method for aerothermoelastic analysis is evaluated by using the hypersonic wing. Results indicate that computational efficiency is improved by about 3.5 times comparing with the aerothermoelastic analysis method that directly employs the RANS method for aerodynamic calculations. Meanwhile, the relative error in the thermal flutter boundary is below 12%
Review: key technologies for wide-body aircraft
No full textWide-body aircraft is the key technical product in the field of civil aviation. The development of wide-body aircraft is the important reflection of national comprehensive strength, as well as the inevitable course to achieve technological autonomy. This paper provides systematic review on the current status and future trend of key technologies for wide-body aircraft in the field of aerodynamics, structure, strength, power plant and main airborne systems, based on the analysis on global wide-body aircraft development. Key technological breakthroughs for wide-body aircraft will primarily focus on areas such as aerodynamic design of high aspect ratio wing with variable camber, nonlinear static aeroelastic design with large deformation, fly-by-wire control law design with more advanced functions, large-scale application of advanced composite structure, structural health monitoring, cockpit integrated warning systems, multi-mode and multi-orbit satellite communication and closed-loop attitude control in flight control systems, etc
Exomoon search with VLTI/GRAVITY around the substellar companion HD 206893 B
No full textContext. This study presents the first application of high-precision astrometry to search for exomoons around substellar companions, as this field remains largely unexplored.
Aims. We investigate whether the orbital motion of the companion HD 206893 B exhibits astrometric residuals consistent with the gravitational influence of an exomoon or binary planet.
Methods. Using the VLTI/GRAVITY instrument, we monitored the astrometric positions of HD 206893 B and c on short (days to months) and long (yearly) timescales. This enabled us to isolate potential residual wobbles in the motion of component B attributable to an orbiting moon.
Results. Our analysis reveals tentative astrometric residuals in the HD 206893 B orbit. If interpreted as an exomoon signature, these residuals correspond to a candidate (HD 206893 B I) with an orbital period of approximately 0.76 years and a mass of ~0.4 Jupiter masses. However, the origin of these residuals remains ambiguous and could be due to systematics. Complementing the astrometry, our analysis of GRAVITY R = 4000 spectroscopy for HD 206893 B confirms a clear detection of water, but no CO was found using cross-correlation. We also found that AF Lep b, and β Pic b are the best short-term candidates to look for moons with GRAVITY+.
Conclusions. Our observations demonstrate the transformative potential of high-precision astrometry in the search for exomoons and proves the feasibility of the technique to detect moons with masses lower than Jupiter and potentially down to less than Neptune in optimistic cases. Crucially, further high-precision astrometric observations with VLTI/GRAVITY are essential to verify the reality and nature of this signal and apply this technique to a range of planetary systems
Contrasting dynamics of energy consumption in MENA countries: Between energy transition and fossil fuel dependency
No full textThis article analyzes energy consumption dynamics in the MENA region, highlighting the contrasts between persistent fossil fuel dependence and emerging renewable energy efforts. Drawing on empirical data, it underscores the differentiated trajectories of regional countries in addressing energy transition challenges. The study sheds light on untapped solar and wind energy potential while examining the challenges tied to policy choices, economic constraints, and regional cooperation. Finally, it emphasizes the need for an integrated and equitable approach to achieve a sustainable energy transition in a context marked by climate urgency and resource pressures
On the relations between morphotectonics, seismicity, perennial and sporadic hydrothermalism on the volcanic island complex of Milos (Greece)
No full textThe volcanic island complex of Milos, situated ∼200 km north of the Hellenic subduction zone, records the interplay of volcanic, tectonic, and gravitational processes within multidirectional, polyphased rift systems that developed throughout the Mio–Plio–Quaternary. Its active and seismogenic fault network hosts both perennial and transient hydrothermal venting zones, offering a natural laboratory to examine fluid circulation within a volcanic arc built on stretched continental crust. This study refines the relationships between magmatism, seismicity, and hydrothermal activity, with implications for local geological hazards.
Two new morpho-tectonic sketches are presented. The first places the Milos volcanic center within the structural framework of the Aegean microplate; the second illustrates the spatial organization of the Milos tectono-hydrothermal-volcanic system. These reconstructions integrate detailed physiographic analyses (relief, slope), field observations, and multidisciplinary datasets on seismicity, hydrothermalism, and mineralization. At the scale of the Aegean microplate, (i) NE–SW faults are attributed to extensional deformation along the Mid-Cycladic Lineament; (ii) E–W faults relate to the opening of the Milos, Cretan, and Christiana basins, parallel to the mid-Miocene West Cycladic Detachments; (iii) NW–SE faults correspond to the Myrtoon Basin and Gulf of Milos openings, the latter being closed to the south by the Fyriplaka volcano; and (iv) N–S faults controlling the Zephyria graben and the eastern margin of Milos are continuous with Cretan fault systems and are parallel both to the Eocene trans-Cycladic thrust in the region and to magnetic anomalies in the subducted Tethyan oceanic crust south of the Hellenic subduction zone.
At the archipelago scale, seismicity, hydrothermal venting, alteration zones, and phreatic explosions are concentrated in the hanging wall of the Achivadolimni fault, along or near the intersections of the N–S Zephyria and NW–SE Fyriplaka grabens, directly above the inferred magma chamber. Microearthquake hypocentres, likely linked to fluid-induced fault dilation, occur beneath the Gulf of Milos (∼7 km) and Fyriplaka volcano (∼5 km). Their distribution suggests a genetic link between the intersecting grabens, cooling of isotherms beneath the gulf by descending seawater, surface hydrothermal manifestations, and tectonic earthquakes (e.g., Mw 5.3 Milos, 1992). A shallow hydrothermal convection loop (<3 km) probably overlies a magmatic reservoir where fluids accumulate beneath a self-sealed, low-permeability cap, possibly corresponding to a thermal brittle-ductile transition (370–450 °C). Co-seismic ruptures may locally breach this barrier, inducing “arterial fault” behaviour along the Achivadolimni fault. Pulsating hydrothermal activity and historical phreatic eruptions are interpreted as surface expressions of transient injections of over-pressurized magmatic fluids, leading to decompression, phase transitions, and fluid expulsion during seismic events. These coupled magmatic-hydrothermal-tectonic processes should be integrated into future hazard assessments for Milos