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Stabilization of blue phases by solvent effect using n-octadecane with a simple linear molecular structure
No full textWe investigated how mixing a n-octadecane with a simple linear molecular structure affects the stability of a liquid-crystalline blue phase (BP). It was found that the addition of the solvent reduces the appearance temperature of the BPs and expands the temperature range over which the BPs are seen. From our measurement, we confirmed that the solvent molecules were dispersed uniformly throughout the liquid-crystal phase. Also, we found that the solvent molecules reduce the splay and bend elastic constants K1 and K3, as well as the ratio K3/K1. We propose that the reduction of K3/K1 by mixing solvent molecules contributes to the stabilization of the BPs, in agreement with existing theoretical predictions
Metal-loaded outflows in sub-Milky Way galaxies in the CIELO simulations
No full textContext. Supernova (SN) feedback-driven galactic outflows are a key physical process that contributes to the baryon cycle by regulating star formation activity, reducing the amount of metals in low-mass galaxies and enriching the circumgalactic (CGM) and intergalactic media (IGM).
Aims. We aim to understand the chemical loop of sub-Milky Way (MW) galaxies and their nearby regions.
Methods. We studied 15 simulated central sub-MW galaxies (M∗ ≤ 1010 M⊙) and intermediate-mass galaxies (M* ∼ 1010 M⊙) from the CIELO-P7 high-resolution simulations. We followed the evolution of the progenitor galaxies, their properties, and the characteristics of the outflows within the redshift range z = [0, 7]. We used two dynamically motivated outflow definitions, unbound outflows, and expelled mass rates to quantify the impact of SN feedback.
Results. At z ∼ 0, sub-MW galaxies have a larger fraction of their current oxygen mass in the gas phase but have expelled a greater portion beyond the virial radius, compared to their higher-mass counterparts. Galaxies with M∗ < ∼ 109 M⊙ have 10–40 percent of their total oxygen mass within R200 in the CGM and an equivalent to 10–60 percent expelled into the IGM. In contrast, more massive galaxies have most of their oxygen mass locked by the stellar populations. The CGM of low-mass galaxies predominantly contains oxygen low-temperature gas, which acts as a metal reservoir. We find that the outflows are more oxygen-rich for sub-MW galaxies, Zout/ZISM ∼ 1.5, than for higher-mass galaxies, Zout/ZISM ≤ 0.5, particularly for z < 2. Mass-loading factors of ηout ∼ 0 − 6 are detected, in agreement with observations. While a weak dependence of η on mass and circular velocity is found at z ∼ 0, a stronger anti-correlation appears for higher redshift.
Conclusions. Our results suggest that sub-MW galaxies may store a significant fraction of metals in their CGM and that the anti-correlation between η and stellar mass (or circular velocity) is stronger at z ∼ 2, which is likely due to a combination of more intense star formation, a higher merger rate, and shallower potential wells
Three-equation turbulent convection models in classical variables
No full textContext. Turbulent convection models in nonlinear radial stellar pulsation models rely on an extra equation for turbulent kinetic energy and fail to adequately explain mode-selection problems. Since multidimensional calculations are computationally expensive, it is reasonable to search for generalizations of physically grounded 1D models that approximate multidimensional results with sufficient accuracy, at least in a given parameter range. A natural way of progressing from one-equation models is to use additional nonlocal equations. While these types of models also exist in the literature, they have not been adopted for this type of object.
Aims. We aim to adapt the three-equation turbulent convection model from Kuhfuss to radial stellar pulsation modeling.
Methods. We use a Reynolds-stress one-point closure approach to derive our extensions alongside the model, while using additional models from the literature to close the anisotropy and dissipation terms.
Results. We provide five extensions to the original model. These include an enhanced dissipation correction to the mixing length, a local anisotropy model replacing eddy viscosity, a second-order correction for turbulent ion transport in the atmosphere (alongside opacity effects), and turbulent damping of entropy fluctuations and convective flux
The bulk metal content of WASP-80 b from joint interior-atmosphere retrievals
No full textThe atmospheres of warm gas giants can be readily characterized through transmission and emission spectroscopy. WASP-80 b is one such exoplanet, with an unusually low density that is in tension with the metal-rich composition expected for a planet of this mass. The aim of this work to derive precise constraints on WASP-80 b's bulk metal mass fraction, atmospheric composition, and thermal structure. We conducted a suite of retrievals using three approaches: traditional interior-only, atmosphere-only, and joint interior-atmosphere retrievals. We coupled the open-source model GASTLI to describe the planetary structure and thermal evolution and petitRADTRANS to describe the atmospheric chemistry and clouds. Our retrievals combined the mass and age with panchromatic spectra from JWST and HST in both transmission (0.5−4 μm) and emission (1–12 μm) as observational constraints. We identified two fiducial scenarios. In the first, WASP-80 b has an internal temperature consistent with its age in the absence of external heating sources; in addition, its atmosphere is in chemical equilibrium, with an atmospheric metallicity of M/H = 2.75−0.56+0.88× solar, a bulk metal mass fraction Zplanet = 0.12 ± 0.02, and a core mass Mcore = 3.49−1.59+3.49 M⊕. In the second scenario, WASP-80 b would be inflated by an additional heat source, possibly induced by magnetic fields, with an atmospheric metallicity of M/H = 10.00−4.75+8.20× solar, Zplanet = 0.28 ± 0 .11, and Mcore = 31.8−17.5+21.3 M⊕. The super-solar M/H and sub-solar C/O ratios in both scenarios suggest late pebble or planetesimal accretion, while additional heating is required to reconcile the data with the more massive core predicted by the core accretion paradigm. In general, joint retrievals are inherently affected by a degeneracy between atmospheric chemistry and internal structure. Taken together with flexible cloud treatment and an unweighted likelihood, this leads to larger uncertainties in bulk and atmospheric compositions than had previously been claimed
CHEX-MATE: New detections and properties of the radio diffuse emission in massive clusters with MeerKAT
No full textModern radio telescopes are revolutionising our understanding of non-thermal phenomena in galaxy clusters, collecting large samples of extended sources with unprecedented sensitivity and angular resolution. In this work, we present novel MeerKAT observations for a sample of 21 galaxy clusters that are part of the CHEX-MATE project. These systems were selected based on their high mass and displaying signs of dynamical activity. Thanks to the high-quality data at hand, we were able to detect extended radio emission in every target considered. We report two new halos, one new relic, and two new candidate relics. We also confirm a previous candidate halo and two candidate relics. After investigating the scaling relations with the cluster properties, we confirmed the presence of a radio halo power-mass correlation and relate it to a higher radio halo emissivity in more massive clusters. For radio relics, we highlight the MeerKAT capabilities to significantly extend the depth of radio observations to a new, unexplored field of low-radio power sources (łesssim 10^ 23 ̊m W Hz^ -1 at 1.28 GHz). Thanks to such high-sensitivity data, we have found that the radio relic power can be characterised by a wide range of values for a given cluster mass and relic size. Ultimately, we discuss how current radio observations, in combination with large radio surveys, are increasingly capable of testing numerical simulation predictions and coming close to performing direct comparisons with their data, enabling new insights on the evolution of radio relics
Acupuncture vs usual care for chronic low back pain: a systematic review and meta-analysis of immediate and intermediate effects
No full textIntroduction: Chronic low back pain (CLBP) is a leading global cause of disability. Acupuncture is increasingly integrated into its management, yet its standalone effectiveness compared to usual care remains uncertain. This review aimed to assess the immediate (≤2 weeks) and intermediate (2 weeks–6 months) effects of acupuncture versus usual care on pain and disability in adults with CLBP. Methods: A systematic review and meta-analysis of randomized controlled trials was conducted, searching MEDLINE, CENTRAL, Scopus, and PEDro through November 2024. Eligible studies compared acupuncture (body, electroacupuncture, scalp) to usual care (physiotherapy, education, medication, and exercise) in adults with CLBP. Outcomes included pain and disability at immediate and intermediate follow-up. Data were pooled using a random-effects model. Risk of bias was assessed with the PEDro scale, and GRADE was used to evaluate evidence certainty. Sensitivity and subgroup analyses were conducted to explore clinical and methodological heterogeneity and test the reliability of findings. Results: A total of 2.956 records were identified, and 8 RCTs (n = 1,123 participants) were included in this study. Acupuncture significantly reduced pain at both immediate (SMD = –0.73, 95% CI –1.04 to –0.42) and intermediate (SMD = –1.13, 95% CI –1.82 to –0.43) timepoints. Disability also improved at both follow-ups (immediate: SMD = –0.49, 95% CI –0.68 to –0.30 and intermediate: SMD = –0.79, 95% CI –1.18 to –0.41). Sensitivity analyses confirmed effect robustness, especially in electroacupuncture subgroups. Certainty of evidence ranged from low to very low due to risk of bias, inconsistency, and suspected publication bias. Discussion: Acupuncture appears more effective than usual care for reducing pain and disability in adults with CLBP, but the certainty of evidence is low, warranting cautious interpretation
Midcarpal tenodeses versus partial arthrodeses for stage II SLAC/SNAC wrists: Long-term outcomes from a single-surgeon comparative series
No full textBackground: Stage II scapholunate advanced collapse (SLAC) and scaphoid nonunion advanced collapse (SNAC) are commonly treated with partial arthrodeses or motion-preserving techniques such as midcarpal tenodeses. Comparative evidence with long-term follow-up remains limited. Purpose: To compare long-term clinical and functional outcomes of midcarpal tenodeses and partial arthrodeses in patients with stage II SLAC/SNAC, by evaluating grip strength, range of motion, patient-reported outcomes, and reoperation rates. Methods: A retrospective review was performed on 21 patients operated by a single surgeon with a mean follow-up of 103 months. Nine underwent midcarpal tenodeses (FCR or ECRB based), and twelve underwent partial arthrodeses (four-corner fusion or capitolunate fusion). Outcomes included grip strength, range of motion, radiographs, and PROMs (VAS, DASH, PRWE, Mayo Wrist Score). Results: Both procedures produced comparable long-term outcomes. Mean postoperative grip strength was 27.9 kg (~75% of the contralateral side). PROMs were similar between groups (DASH 12.1, PRWE 15.5). Importantly, no complications, non-unions, or conversions to salvage arthrodesis occurred in either group during long-term follow-up. Conclusion: Midcarpal tenodeses and partial arthrodeses yield similarly durable outcomes in stage II SLAC/SNAC wrists. Tenodeses preserve motion and are suitable for patients with preserved cartilage, whereas partial arthrodeses offer predictable stability when midcarpal degeneration is present. Treatment should be individualized according to cartilage status, functional demands, and patient expectations
Experimental and numerical analysis verification of effect of work material in cylindrical deep drawing focusing on material anisotropy and die radius shape
No full textThis paper presents the effect of work material on the formed shape in a cylindrical deep drawing using a die with circumferentially varying die radius dimensions. In the deep drawing, the material anisotropy causes unevenness, called “ears”, on the cup edge. Because of the additional trimming process, the occurrence of earing leads to material loss and additional production processes, resulting in low productivity. The earing suppression has usually been conducted by material development to suppress material anisotropy. It has been shown that a die with different die radius dimensions has been proposed, and that the ear shape can be changed by the die only. However, the effects of material thickness, diameter, and anisotropy on the formed shape have not been reported. In this paper, the effects of forming conditions of mainly the material were investigated by experiments and finite element analysis in cylindrical deep drawing using a die with circumferentially varying die radius dimensions. As the sheet thickness was thicker and the blank diameter was larger, the ear height increased due to the large material inflow. Stainless steel, aluminum alloy, and copper materials can be used to suppress ear height if appropriate forming conditions are set. It has also been clarified that there are conditions of die placement that suppress the ear height in correlation with the in-plane anisotropy of the material
Optimum Asymmetric Spatial and Temporal Distribution of Femtosecond Laser Pulses in Refractive Surgery
No full textFemtosecond laser–assisted refractive correction relies on temporally and spatially separated pulses that generate coalescent cavitation bubbles, forming a cleavage plane for tissue separation. Achieving optimal outcomes requires balancing laser-induced stress, mechanical dissection stress, and surface roughness. This work introduces a nonlinear absorption model and a theoretical framework to identify the optimum spatial and temporal distribution of single pulses. The analysis, based on inequalities involving scaling factors for spot size and track distance, defines a bounded solution space. Within this domain, the most favorable setting corresponds to minimum dose with maximum asymmetry, ensuring energy efficiency while enhancing surface smoothness, whereas the least advantageous of the optimum conditions occurs for higher dose and minimum asymmetry (compatible with optimum conditions) both enabling a theoretical bridge-free dissection. Bubble overlap emerges as a key determinant of cutting efficiency and smoothness, and an optimal window for overlap factors is delineated, minimizing treatment dose while preserving corneal quality through smoother stromal cuts
Luminescent thermal history sensing potential in Pr³⁺-activated YAG matrix
No full textIn this study, it was demonstrated that Pr³⁺-doped YAG powder can record thermal history in the temperature range of template provided by 1100–1600°C. Upon heating, the material undergoes irreversible structural phase transformations (YAM → YAP → single-phase YAG) induced by 2 h of thermal annealing, leading to permanent changes in both the emission intensity and the excited-state lifetime of Pr³⁺ ion. Temperature can be determined using two approaches: by analyzing the intensity ratio of the ³P₀→³H₄ and ¹D₂→³H₄ emission bands, which increases linearly over 1300–1600°C with a sensitivity of 0.001°C⁻¹, and by measuring the luminescence decay time of the ¹D₂→³H₄ transition, which decreases linearly over 1100–1600°C with a sensitivity of 0.38 µs·°C⁻¹. The combination of both methods enables durable and quantitative tracking of the material’s thermal history, confirming the suitability of YAG:Pr³⁺ powders for high-temperature diagnostics, thermal mapping, and monitoring of industrial processes