Abstract We present the first detailed multiband ($BVR_cI_c$ and TESS) photometric analysis of the short-period binary EZ Oct. This study combines ground-based observations conducted at a Southern Hemisphere observatory in Argentina with data from the TESS mission. Investigating the orbital period variations of EZ Oct reveals a steadily increasing period consistent with a quadratic trend. We present a new ephemeris and estimate the mass transfer rate as $\dot{M}=1.353\times 10^{-8}$ $M_{\odot}$/year, indicating ongoing conservative mass transfer from the less massive to the more massive star. Light curve modeling was performed using the PHOEBE Python code in conjunction with the MCMC approach, and the inclusion of a cold starspot was required to achieve an adequate fit. Absolute parameters were estimated using Gaia DR3 parallax and astrophysical equations. Our analysis shows that EZ Oct is a total-eclipse contact binary with a mass ratio of 1.969, a fillout factor of 0.106, and an inclination of $82.13^\circ$. Based on the stellar masses and temperatures of the components, the target system belongs to the W-subtype of contact binaries. The positions of the component stars were displayed on the mass–luminosity and mass–radius diagrams to illustrate their evolutionary status. Moreover, we investigated the relationship between orbital period and stellar luminosity in contact binary stars using a sample of 461 systems with $P < 0.5$ days. We highlight the position of EZ Oct in the mass ratio–inclination parameter space, showing that it lies within the densely populated region of contact binaries.

We study the equilibrium phases of a generalized Lotka-Volterra model characterized by a species interaction matrix which is random, sparse, and symmetric. Dynamical fluctuations are modeled by a demographic noise with amplitude proportional to the effective temperature T . The equilibrium distribution of species abundances is obtained by means of the cavity method and the Belief Propagation equations, which allow for an exact solution on sparse networks. Our results reveal a rich and nontrivial phenomenology that deviates significantly from the predictions of fully connected models. Consistently with data from real ecosystems, which are characterized by sparse rather than dense interaction networks, we find strong deviations from Gaussianity in the distribution of abundances. In addition to the study of these deviations from Gaussianity, which are not related to multiple equilibria, we also identified a novel topological multiple-attractor phase, present at both finite temperature, as shown here and at T = 0 , as previously suggested in the literature. The peculiarity of this phase, which differs from the multiple-equilibria phase of fully connected networks, is its strong dependence on the presence of extinctions. These findings provide new insights into how network topology and disorder influence ecological networks, particularly emphasizing that sparsity is a crucial feature for accurately modeling real-world ecological phenomena.

Lateral charge transport of a two-dimensional (2D) electronic system can be much influenced by feeding a current into another closely spaced 2D conductor, known as the Coulomb drag phenomenon - a powerful probe of electron-electron interactions and collective excitations. Here, we show that Coulomb drag in a deliberately asymmetric van der Waals bilayer can serve as a layer-selective probe of electronic compressibility that remains invisible to standard transport. We devise a MoS2/graphene double layer with large disparity in effective mass and Fermi temperature between them, separated by a~ 3 nm hexagonal boron nitride spacer, and operate in the degenerate Fermi liquid regime. The MoS2 drag channel exhibits constant electronic compressibility and acts as a sensitive transducer of graphene's Landau-level physics at finite magnetic fields. At elevated temperatures and moderate magnetic fields, clear Shubnikov-de Haas-like behaviour in the drag signal tracks the quantum oscillation in compressibility of graphene even when its own magnetotransport remains essentially featureless under the same conditions. Our results establish asymmetric Coulomb drag as a compressibility spectroscopy for 2D systems, enabling access to quantum phenomena that may leave only weak, or even negligible, fingerprints in transport.

Abstract The metallicity of the star-forming environment is a fundamental parameter shaping the evolution of protoplanetary disks and the formation of planetary systems, yet its influence remains poorly constrained. We present a spectroscopic study of low-mass pre-main-sequence (PMS) stars ( M < 1 M ⊙ ) in the exceptionally metal-poor cluster Dolidze 25 ( Z ≈ 0.2 Z ⊙ ), using Very Large Telescope/MUSE observations to probe accretion processes and disk evolution in a subsolar environment. We identify 132 cluster members using a combination of Gaia astrometry and spectroscopic youth indicators, including lithium absorption and Balmer emission. The stellar parameters are derived using low-metallicity BT-Settl models yielding effective temperatures, extinctions, and luminosities enabling robust estimates of stellar masses and ages. Mass accretion rates ( M ̇ acc ) derived from H α emission span 10 −10 –10 −8 M ⊙ yr −1 with a median value of 8 × 10 −10 M ⊙ yr −1 . These rates are comparable to those in solar-metallicity regions of a similar age, such as Lupus and Orion, indicating minimal metallicity dependence in accretion processes. Our analysis shows that using solar-metallicity templates to fit low-metallicity stars leads to systematic overestimations of T eff (by approximately 300 K) and A V (by around 0.5 mag), underscoring the importance of employing metallicity-matched models for reliable characterization in low- Z environments. We present flux-calibrated, extinction-corrected spectra of these metal-poor PMS stars as a valuable resource for future investigations of disk evolution in subsolar regimes.

Abstract In addition to comprehensive surveys of the Milky Way (MW) bulge, disk, and halo, the Apache Point Galactic Evolution Experiment (APOGEE) project observed seven dwarf spheroidal satellites (dSphs) of the MW: Carina, Sextans, Sculptor, Draco, Ursa Minor, Bootes 1, and Fornax. APOGEE radial velocities, stellar parameters, and Gaia EDR3 proper motions are used to identify member stars from the targets in the vicinity of each dwarf; for seven dwarfs, new member stars are identified. To properly analyze the abundance patterns of these galaxies, a novel procedure was developed to determine the measurable upper limits of the APOGEE chemical abundances as a function of the effective temperature and the spectral signal-to-noise ratio. In general, the APOGEE abundance patterns of these galaxies (limited to [Fe/H] > −2.5) agree with those found in high-resolution optical studies in the literature after abundance offsets are applied. Most of the galaxies studied here have abundance patterns that are distinctly different from the majority of stars found in the MW halo, suggesting that these galaxies contributed little to the MW halo above [Fe/H] > −2.0. From these abundance patterns, we also find that these dSphs tend to follow two types of chemical evolution paths: episodic and continuous star formation, a result that is broadly consistent with previous photometric studies of the star formation histories (SFHs) of these galaxies. We explore whether mass and/or environment have an impact on whether a galaxy has an episodic or continuous SFH, finding tentative evidence that, in addition to the galaxy’s mass, proximity to a larger galaxy and the cessation of star formation may drive the overall shape of the chemical evolution.

Abstract We have obtained a high-resolution, JWST NIRSpec 2.87–5.14 μ m spectrum of the debris disk around HD 131488. We discover CO fundamental emission indicating the presence of warm fluorescent gas within ∼10 au of the star. The large discrepancy in CO’s vibrational and rotational temperature indicates that CO is out of thermal equilibrium and is excited with UV fluorescence. Our UV fluorescence model gives a best fit of 1150 K with an effective temperature of 450, 332, and 125 K for the warm CO gas kinetic temperature within 0.5, 1, and 10 au to the star and a gas vibrational temperature of 8800 K. The newly discovered warm CO gas population likely resides between sub–astronomical unit scales and ∼10 au, interior to the cold CO reservoir detected beyond 35 au with the Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph and Atacama Large Millimeter/submillimeter Array (ALMA). The discovery of warm, fluorescent gas in a debris disk is the first such detection ever made. The detection of warm CO raises the possibility of unseen molecules (H 2 O, H 2 , etc.) as collisional partners to excite the warm gas. We estimated a lower mass limit for CO of 1.25 × 10 −7 M ⊕ , which is 10 −5 of the cold CO mass detected with ALMA and HST. We demonstrate that UV fluorescence emerges as a promising avenue for detecting tenuous gas at 10 −7 Earth-mass level in debris disks with JWST.

To enhance the wide-temperature-range magnetocaloric performance of (Mn,Fe)2(P,Si) alloys, the effects of Mg-Co co-doping on their structural and magnetocaloric properties were systematically investigated. Mn1.05−yCoyFe0.9P0.5Si0.48Mg0.02 alloys were prepared by the arc melting method. The results show that Mg-Co co-doping can tune the lattice parameters and ferromagnetic coupling between Mn and Fe atoms. The Mn1.03Co0.02Fe0.9P0.5Si0.48Mg0.02 alloy exhibited an effective refrigeration capacity of 425.4 J·kg−1 and an effective working temperature span of 52 K. During the temperature-induced ferromagnetic transition, coupling between the magnetic moment of Fe-Si layers and the crystal lattice drives a magnetoelastic transition, leading to a giant magnetocaloric effect. The Mg-Co co-doping strategy effectively tunes the crystal structure and local electron density distribution of the Fe-Si layer, thereby influencing the total magnetic moment and magnetothermal properties of the alloys.

Effective temperature control of a battery thermal management system with a backup thermoelectric cooling source

Abstract Gadolinium (Gd) is the benchmark magnetocaloric material, yet its performance requires optimization in working temperature range, refrigeration capacity (RC) and heat exchange capacity. Here, we address this by a synergistic strategy combining Co alloying (to create an in-situ dual-phase magnetocaloric system) and the melt-extraction technique (to directly shape the alloy into microwires). This approach fabricates Gd 87.5 Co 12.5 (at.%) crystalline/crystalline composite microwires. The resulting microstructure comprises a Gd-rich matrix embedded with magnetocaloric Gd 3 Co phase, both of which are crystalline. This dual-phase architecture yields a remarkable magnetic entropy change (-Δ S m ) profile, which delivers an ultra-broad effective temperature span ( δT ) of 218.5 K (defined between the outer half-maximum points of the dual-peak magnetic entropy change vs temperature curve, 107.6–326.1 K) and a high RC of 658.7 J/kg under 5 T. To our knowledge, this work represents the first investigation of the magnetocaloric effect (MCE) in Gd-based crystalline/crystalline composite microwires. More importantly, it validates a dual-route design paradigm: phase-composition engineering for broadened δT and RC, coupled with morphology engineering via melt-extraction for enhanced heat exchange. This work establishes a new paradigm for designing next-generation magnetocaloric materials with integrated performance enhancements, particularly for efficient magnetic refrigeration in applications like gas liquefaction.

In this work, we present a proof‐of‐concept demonstration of inkjet‐printed resistive temperature sensors based on nanoparticle platinum ink on flexible polyimide substrates. The resistive temperature sensors are designed as meander structures with a target nominal resistance of 100 and 1000 Ω to be compared to conventional bulk Pt100 and Pt1000 resistors. Thermogravimetric analysis and in situ resistance measurements identified 250°C as the optimal sintering temperature, enabling sufficient solvent removal for conductive structure formation while avoiding Pt surface oxidation and polyimide substrate degradation. Electrical characterization in the 20°C–80°C range revealed a linear relationship between resistance and temperature with effective temperature coefficients of resistance (~48%/57%) and sensitivities (~72%/87%) compared to Pt100/Pt1000 standards, respectively. Mechanical testing over 400 bending cycles showed less than 1% change in electrical resistance, confirming robust flexibility. This study demonstrates the feasibility of translating nanoparticle Pt‐based resistive temperature sensors into flexible and automotive sensing applications, offering low‐temperature processability, stable temperature coefficients of resistance, linear sensitivity, mechanical robustness, and chemical stability across 20°C–80°C range.

Reliable measurement of multiphase flow is fundamental to production evaluation in complex oil and gas wells. However, conventional sensors often suffer from low integration, limited measurement capability, and potential environmental impact. To address these challenges, a photoelectric composite three-phase flow sensor is developed, integrating multiple electrode rings for water holdup and liquid-phase velocity measurement, with dual optical-fiber probes for gas holdup and gas-phase velocity detection. A slip model is further applied to quantify the dependence of slip velocity on liquid holdup based on measured phase rates. Experimental results demonstrate high sensitivity to bubble-flow structures, accurate extraction of gas holdup and phase velocities, and stable full-range water holdup calibration from 0% to 100% at 5 V and 15 V with effective temperature and salinity compensation. And compared with existing technologies, the sensor designed in this paper has the advantages of high integration, a simple structure, multiple measurement parameters, and higher water-holding capacity resolution in low-saturation areas, providing more advanced technical means for conventional profile three-phase flow logging.

While dephasing noise often hinders quantum devices, it can become an asset for quantum thermal machines. Here we demonstrate a three-level thermal machine that leverages noise-assisted quantum transport to enable steady-state cooling of microwave modes. The device exploits symmetry-selective couplings between a superconducting artificial molecule and two physical heat baths. Each bath consists of a microwave waveguide populated with synthesized quasithermal radiation. Energy transport is enabled by injecting dephasing noise through a third channel longitudinally coupled to one artificial atom of the molecule. By varying the effective temperatures of the reservoirs and measuring photonic heat currents with sub-attowatt resolution, we demonstrate energy flow dynamics characteristic of a quantum heat engine, thermal accelerator, and refrigerator. Our work constitutes an experimental demonstration of the key operating principles of a noise-assisted three-level quantum refrigerator and opens new avenues for experiments in quantum thermodynamics using superconducting circuits coupled to physical heat baths.

Climate variability necessitates the optimization of sowing dates for vegetable crops to stabilize yields and mitigate abiotic stress risks. This study aimed to evaluate the effect of sowing dates on the productivity of daikon radish (Raphanus sativus L. convar. acanthiformis Sazon.) cultivars Gulliver and Minowase under medium-podzolic, light loamy soil conditions with a pH (pHKCl) of 6.74 during the period 2022–2024. Field experiments were conducted across four sowing dates (ranging from July to early August), accounting for the hydrothermal conditions of the growing season. Effective air temperatures ranged from 428 to 950 °C, with precipitation levels between 36.9 and 252.3 mm. It was established that the sowing date significantly influenced daikon yield (p < 0.001). A significant positive correlation was identified between yield and precipitation (r = 0.76–0.84; p < 0.05), whereas the correlation between yield and the sum of effective temperatures was weak to moderate and predominantly negative (r = −0.62 to −0.10). The highest yields were achieved with sowing in the third ten-day period of July: 54.6 t ha−1 for the Gulliver cultivar and 58.9 t ha−1 for the Minowase cultivar. The Minowase cultivar consistently outperformed Gulliver in terms of yield and exhibited higher ecological plasticity under fluctuating hydrothermal conditions. These findings confirm the feasibility of optimizing sowing dates as an effective adaptive tool for enhancing the stability of daikon production amidst climate change.

Abstract This work provides an analysis of p T spectra for identified hadrons generated during gold–gold collisions at a center-of-mass energy ( s N N ) of 11.5 GeV. The data, recorded by the STAR detector at the Relativistic Heavy Ion Collider, is evaluated using predictions from phenomenological models. Specifically, we compare the outcomes of Monte Carlo simulations from Pythia 8.3 and EPOS (comprising EPOS4 and EPOSLHC) with experimental observations. Our investigation focuses on π ± , K ± , and (anti-)proton spectra measured at mid-rapidity (∣ y ∣ < 0.1) across nine distinct centrality classes. In the case of π ± , EPOS4 model shows good agreement with the data only in the low p T region. However, it successfully reproduces the results across the entire p T range for the last three centrality classes for pions yields. In the case of K ± , EPOS4 exhibit good agreement with the experimental data. For proton and (anti-)proton, this model mostly underestimates in high- p T region, likely due to the reduced interaction volume and lower rescattering probability. In contrast, Pythia 8.3 often overpredicts pion yields and provides consistent representations for kaons and for (anti-)protons, Pythia 8.3 and EPOSLHC fails to describe the data. Pythia 8.3 mostly overestimates the data in the case of proton. EPOS4 demonstrates a good description of pion spectra compared to Pythia 8.3, largely attributable to its inclusion of hadronic rescattering effects. Meanwhile, EPOSLHC shows better alignment with experimental data in the case of kaons and proton for the entire p T range while for pions it also better reproduced the result at higher p T only. At higher p T , EPOSLHC exhibits a suppression relative to the experimental data, indicating limitations of the model description in a momentum region where collective flow effects are expected to be minimal. EPOS4 and EPOSLHC outperform Pythia 8.3, primarily due to their ability to incorporate correlated flow dynamics and hadronic rescattering effects. In contrast, Pythia 8.3 lacks these mechanisms, leading to less precise spectral descriptions. None of the models accurately replicate the experimental data for the (70–80)% centrality class likely due to the absence of collective effects and the increased role of non-equilibrium dynamics in these events. Additionally, the extracted freeze-out parameters indicate a rise in effective temperature and a decrease in the non-extensive parameter with increasing centrality. These trends suggest greater system excitation and more rapid thermal equilibration in highly central collisions.

Abstract We present high-precision chemical abundances for 20 FGK stars hosting planets observed in JWST Cycle 2 GO programs. Using high-resolution, high-signal-to-noise ratio spectra from the ESO and Keck archives, we perform a strict line-by-line differential analysis relative to the Sun to derive stellar parameters and abundances of 19 elements from C to Zn. The stars span effective temperatures of 4500–6500 K and metallicities from −0.57 to +0.50 dex. The sample includes hosts of both gas giants and terrestrial planets, allowing direct comparison between stellar composition and planetary properties. Several of the giant planets orbit metal-rich stars. The detailed abundance patterns show clear chemical diversity, including carbon-enhanced but mildly metal-poor stars (TOI-824, TOI-561, TOI-1130, GJ 9827) and α -enhanced metal-poor stars (TOI-561, GJ 9827, TOI-824). These variations trace differences in protoplanetary disk composition and may influence planetary interiors and atmospheric chemistry. The planet hosts show a range of [C/O] ratios, and the diverse [Mg/Si] ratios may suggest varied interior compositions for their rocky planets. This homogeneous stellar abundance, together with future uniform JWST planetary atmosphere measurements, provides a foundation for exploring the planet mass–metallicity relation and the connection between stellar chemistry and planetary formation pathways. These results constitute the first step in a larger survey spanning multiple JWST cycles to systematically examine how host star composition shapes exoplanetary systems.

Abstract We report the discovery of LAMOST J0041+3948, the most luminous post-asymptotic giant-branch (AGB) Type II Cepheid known, located in the Andromeda Giant Stellar Stream. Its spectral energy distribution (SED) exhibits a strong near-infrared excess, indicating the presence of a circumbinary dusty disk and hence binarity. SED fitting yields an effective temperature of T eff = 673 8 − 262 + 234 K and a post-AGB luminosity of log ( L / L ⊙ ) = 4.3 2 − 0.08 + 0.07 . Comparison with theoretical evolutionary tracks suggests a ∼2.0–4.0 M ⊙ progenitor when accounting for a possible scattered-light contribution. Zwicky Transient Facility light curves reveal a pulsation period of 89 days that lies close to the period–luminosity relation for long-period RV Tauri stars. Follow-up spectroscopy reveals clear s -process enrichment and signatures consistent with an accretion disk around the companion. The inferred progenitor is significantly younger and more massive than a typical stream member, suggesting that an additional mechanism, such as a stellar merger, is required. We propose a formation channel in which the present post-AGB binary descends from a hierarchical triple system. In this scenario, the inner binary merged after the system was displaced to its current location by the galaxy merger event, and the resulting massive merger remnant subsequently evolved into the extremely luminous post-AGB star observed today.

Proton and charge transfer are two commonly observed reaction mechanisms in the chemical ionisation of neutral analytes in mass spectrometry and ion mobility spectrometry. While those reactions show a strong influence on effective temperature, influenced by the applied electric field strengths, a detailed understanding of the underlying mechanisms under such conditions is still lacking. Using a high kinetic energy ion mobility spectrometer, we examine the reaction dynamics of proton transfer from H3O+(H2O)n and charge transfer from NO+(H2O)m to the model analytes benzene, toluene, and p-xylene experimentally and compare this to quantum chemical modelling of the ionisation processes over a wide range of effective temperatures. Our findings underline that the reduced field strength (E/N) significantly affects the ion-neutral reactions due to its influence on effective temperature, leading to significant changes in reaction rate coefficients. Particularly when ionisation proceeds via H3O+ and NO+, the reaction rate coefficients approach the association rate in most cases. However, hydration of the reactant ions can slow down the reaction since the dynamics of intermediate reaction complexes need to be considered, as these can introduce additional internal barriers. Especially when subjected to high E/N, those reaction complexes can either dissociate back to the reactants or towards the products, with the branching ratio determined by the kinetics of both reaction paths. Particularly when the ionisation energies or proton affinities of the neutral precursor of the reactant ion and the neutral analyte are similar, this product branching can introduce deviations between the experimentally observed reaction rates and the association rates.

Cities in India experience distinct seasons, including summer, winter and monsoons. the understanding of thermal comfort within modern houses throughout the different seasons is pivotal for determining a passive design strategy for residences, towards carbon neutrality. Long-term investigations were conducted within five typical houses in the warm–humid climate of Kharagpur, India, spanning three seasons from July 2023 to July 2024. These included air temperature (AT), relative humidity (RH), indoor wind speed and globe temperature for calculating standard effective temperature (SET*). The SET* was used in thermal comfort evaluation, focusing on the cooling effects of elevated wind speeds. The results showed that indoor ATs were well stabilized among the houses, ranging from 27 to 32 °C in monsoon, 20 to 23 °C in winter and 30 to 32 °C in summer on average, due to the effects of high thermal mass structure with relatively small openings. Overall, both the house-wise differences (1–2 °C) and diurnal differences (0.5–3 °C) were much smaller than the seasonal differences. It was found that the resultant indoor operative temperatures (OTs) did not fall within the required comfort levels during the summer and monsoons, whereas those of the winter months met the required standard. The current modern Indian houses of high thermal mass structure prevented flexible adaptations to the dynamic seasonal changes as well as changes within a day. The occupants tended to reduce the SET* by increasing the wind speeds with the assistance of mechanical air circulation, thus reducing the perceived AT by 5 °C in summers. Separate design strategies should be adopted seasonally and in different parts of the day, to maintain a thermally comfortable environment for the occupants.

Abstract This study investigates the transverse momentum (pT ) distributions of π∓, K∓, p(¯p), K0s , and Λ in various centrality classes of Pb–Pb collisions at √sN N = 2.76 TeV. The experimental spectra are analyzed using the Tsallis non-extensive distribution, from which the effective temperature (T ), non-extensive parameter (q), and mean transverse momentum (⟨pT ⟩) are extracted for each particle species and centrality bin. To disentangle thermal and collective effects, the mean kinetic freeze-out temperature (⟨T0⟩) is obtained from the intercept of the T versus mass relation, while the average transverse flow velocity (⟨βT ⟩) is extracted from the slope of ⟨pT ⟩ versus mean moving mass for pions, kaons, and protons. The results show that T increases and q decreases with centrality, indicating a hotter and more equilibrated system in central collisions. A clear mass dependence of
T supports the presence of a multi-freeze-out scenario, with heavier particles decoupling earlier. Both ⟨T0⟩ and ⟨βT ⟩ rise from peripheral to mid-central collisions before saturating toward central events, which may suggest the onset of collective behavior or changes in freeze-out dynamics. These observations provide new insights into the thermal and dynamical properties of the medium created in heavy-ion collisions at the LHC.

Ammonium nitrogen (NH4+-N) removal and recovery from wastewater have been critical issues worldwide and key to achieving a sustainable nitrogen cycle and circular economy. In this study, we designed and constructed a pilot-scale air stripping system integrated with a nutrient-capture unit and evaluated the effective pH, temperature, and airflow conditions for maximising NH4+-N removal and recovery from dairy processing wastewater (DPW). Our results demonstrated that increasing pH and temperature substantially enhances NH4+-N removal via air stripping, with higher airflow rates further improving performance. Under these conditions (pH 11, 32 °C, and 300 L min−1), NH4+-N removal from synthetic wastewater reached ≈40% after 6 h air stripping. In comparison, real DPW exhibited slightly lower removal efficiency under the same conditions, achieving ≈34%, likely due to its more complex matrix. Additionally, incorporating a chemical precipitation step followed by filtration prior to air stripping removed NH4+-N from DPW, achieving ≈43%. However, extending the stripping duration under identical conditions significantly improved removal performance, increasing NH4+-N removal in DPW to ≈70%. The downstream capturing system, consisting of acid bath and granulated activated carbon (GAC), consistently recovered 70–95% of the released ammonia (NH3) when even upstream NH4+-N removal via air stripping was moderate. The GAC effectively adsorbed the volatilised NH3, achieving adsorption capacities of up to ≈18 mg/kg. Overall, this integrated system demonstrates strong potential for simultaneous NH4+-N removal and recovery from industrial wastewater streams, offering notable environmental benefits.