Equilibrium Effects Research Articles

On the Pair-instability Supernova Origin of J1010+2358* * Based on observations made with the Very Large Telescope (VLT) of the ESO at the La Silla Paranal Observatory under the program ID 112.26WJ.001

The first (Population III) stars formed only out of H and He and were likely more massive than present-day stars. Massive Population III stars in the range 140–260 M ⊙ are predicted to end their lives as pair-instability supernovae (PISNe), enriching the environment with a unique abundance pattern, with high ratios of odd to even elements. Recently, the most promising candidate for a pure descendant of a zero-metallicity massive PISN (260 M ⊙) was discovered by the LAMOST survey, the star J1010+2358. However, key elements to verify the high PISN contribution, C and Al, were missing from the analysis. To rectify this, we obtained and analyzed a high-resolution Very Large Telescope/UVES spectrum, correcting for 3D and/or non-local thermodynamic equilibrium effects. Our measurements of both C and Al give much higher values (∼1 dex) than expected from a 260 M ⊙ PISN. Furthermore, we find significant discrepancies with the previous analysis and therefore a much less pronounced odd–even pattern. Our results show that J1010+2358 cannot be a pure descendant of a 260 M ⊙ PISN. Instead, we find that the best-fit model consists of a 13 M ⊙ Population II core-collapse supernova combined with a Population III supernova. Alternative, less favored solutions ( χ2/χbest2≈2.3 ) include a 50% contribution from a 260 M ⊙ PISN or a 40% contribution from a Population III Type Ia supernova. Ultimately, J1010+2358 is certainly a unique star giving insights into the earliest chemical enrichment; however, this star is not a pure PISN descendant.

Factor reallocation path for low-carbon transformation: A perspective of manufacturing industry ecosystem

The incomplete production factor market induces more factors flowing to industries with lower carbon productivity, highlighting the need for effective factor reallocation to promote low-carbon transformation. Current research is constrained by the dimension of factor endowments, with insufficient attention given to the problem of diminishing marginal benefit of factor input in factor reallocation. By combining the factor flow effect induced by productivity difference with the factor allocation equilibrium effect under diminishing marginal benefit, the factor reallocation path for low-carbon transformation is analyzed using random forest algorithm within a high-dimensional data environment from the perspective of manufacturing industry ecosystem. The results indicate that effective factor reallocation for low-carbon transformation depends on breaking the dual segmentation of factors between regions and industries to facilitate flow of factors from shrub layer industries to canopy layer industries. Adjusting key factor combinations to fall within the optimal equilibrium interval of S-shaped or anti S-shaped partial dependence curves maximizes the marginal benefits of low-carbon transformation. Industries must upgrade their factor endowment structure to accumulate essential carrying capacities that support advanced manufacturing, leveraging the low-carbon transformation dividends of advanced factors inflow and technology spillover. Otherwise, aligning with regional factor comparative advantage to cultivate differentiated characteristic manufacturing industries offers a promising alternative, capitalizing on the low-carbon efficiency premium derived from specialized division of labor.

Crowding in Private Quality: The Equilibrium Effects of Public Spending in Education

Abstract We estimate the equilibrium effects of a public school grant program administered through school councils in Pakistani villages with multiple public and private schools and clearly defined catchment boundaries. The program was randomized at the village level, allowing us to estimate its causal impact on the market. Four years after the start of the program, test scores were 0.2 standard deviations higher in public schools. We find evidence of an education multiplier: test scores in private schools were also 0.2 standard deviations higher in treated markets. Consistent with standard models of product differentiation, the education multiplier is greater for those private schools that faced a greater threat to their market power. Accounting for private sector responses increases the program’s cost-effectiveness by 85% and affects how a policy maker would target spending. Given that markets with several public and private schools are now pervasive in low- and middle-income countries, prudent policy requires us to account for private sector responses to public policy, both in policies’ design and evaluation.

Application of poly(L-lactic acid)-based films for equilibrium modified atmosphere packaging of “Kyoho” grapes and its favorable protection for anthocyanins

Grapes were packaged by different Poly (L-lactic acid)-based packaging films (PLTL-PLEL) and stored at 5 °C for 35 days to investigate the effects of equilibrium modified atmosphere packaging on the quality of “Kyoho” grapes during storage. Changes in physiochemical quality, antioxidant content and senescence of grapes were studied. Furthermore, UPLC-Q-TOF-MS/MS was used to observe and identify key factors influencing the variation of grape anthocyanins under different atmosphere conditions. Alterations in gas components and enzyme activities significantly impacted anthocyanin levels, highlighting oxygen concentration as the primary influence on total anthocyanin levels. The PLTL-PLEL50 packaging resulted in an approximate 5.7% lower weight loss and increased soluble solids by approximately 14.4%, vitamin C, total phenols and flavonoids reaching 60.2 mg/100 g, 8.4 mg/100 g and 7.2 mg/100 g, respectively. This packaging also preserved higher anthocyanin levels, with malvidin-3-glucoside and peonidin-3-glucoside at 0.55 μg/mL and 1.62 μg/mL, respectively, on the 35th day of storage.

Accommodating the Rise in Urbanisation: Are New Towns a Good Solution?

Abstract This paper studies the performance of New Towns, that is, planned large urban sub-centres, as a central tool to accommodate the global rise in urbanisation. A spatial quantifiable general equilibrium framework suitable to study large-scale urban master plans is presented. The framework is then used to investigate the equilibrium effects of five New Towns developed in the 1970s in Paris’s metropolitan area. By 2015, the development of New Towns appears to have increased metropolitan population ($+$18%), metropolitan gross domestic product ($+$11%) and reduced average commuting times (−6.9%). The results obtained for Paris’s metropolitan area are externally validated using a difference-in-differences approach on all 314 New Towns developed worldwide between 1992 and 2012.

Construction of a Spatial Equalization Assessment System for Medical Facilities

The spatial equalization of medical facilities can alleviate the wastage of medical resources and improve the efficiency of medical services. Therefore, it is necessary to carry out spatially balanced planning and assessment of medical facilities in cities. Existing studies on the balanced planning, design, and evaluation of medical facilities have been conducted from the perspective of hospital buildings in terms of spatial utilization efficiency, service satisfaction, and their physical environment on one hand, and from the perspective of regional planning of medical facilities in terms of spatial accessibility to medical facilities and the suitability of medical facilities to the social environment on the other hand. This study hopes to break down the boundaries of each perspective and effectively integrate the architecture, planning, and social well-being of medical facilities, taking spatial equilibrium as the core, in order to establish a spatial equilibrium system for medical facilities and achieve a spatial equilibrium-based assessment of the current state of medical facilities. First, the factors influencing the spatial equilibrium of hospital buildings with the support of the system and environment of hospital buildings are determined. Second, the indicators of the spatial equilibrium of hospital buildings are extracted through the consideration of influencing factors, and the indicator weights are determined by discussing the degree to which they contribute to the influence of the operation of hospital building spatial equilibrium systems, thus forming a system of equilibrium indicators for hospital buildings. Finally, a spatial equilibrium evaluation model for hospital buildings is established to assess the effects of equilibrium. The results obtained in this study provide insights into the regional planning of medical facilities and the design of hospital buildings.

One-dimensional, geometrically stratified semi-empirical models of the quiet-Sun photosphere and lower chromosphere

One-dimensional, semi-empirical models of the solar atmosphere are widely employed in numerous contexts within solar physics, ranging from the determination of element abundances and atomic parameters to studies of the solar irradiance and from Stokes inversions to coronal extrapolations. These models provide the physical parameters (i.e. temperature, gas pressure, etc.) in the solar atmosphere as a function of the continuum optical depth $ c $. The transformation to the geometrical $z$ scale (i.e. vertical coordinate) is provided via vertical hydrostatic equilibrium. Our aim is to provide updated, one-dimensional, semi-empirical models of the solar atmosphere as a function of $z,$ but employing the more general case of three-dimensional magneto-hydrostatic equilibrium (MHS) instead of vertical hydrostatic equilibrium (HE). We employed a recently developed Stokes inversion code that, along with non-local thermodynamic equilibrium effects, considers MHS instead of HE. This code is applied to spatially and temporally resolved spectropolarimetric observations of the quiet Sun obtained with the CRISP instrument attached to the Swedish Solar Telescope. We provide average models for granules, intergranules, dark magnetic elements, and overall quiet-Sun as a function of both $ c $ and $z$ from the photosphere to the lower chromosphere. We demonstrate that, in these quiet-Sun models, the effect of considering MHS instead of HE is negligible. However, employing MHS increases the consistency of the inversion results before averaging. We surmise that in regions with stronger magnetic fields (i.e. pores, sunspots, network) the benefits of employing the magneto-hydrostatic approximation will be much more palpable.

ReMKiT1D - A framework for building reactive multi-fluid models of the tokamak scrape-off layer with coupled electron kinetics in 1D

In this manuscript we present the recently developed flexible framework for building both fluid and electron kinetic models of the tokamak Scrape-Off Layer in 1D - ReMKiT1D (Reactive Multi-fluid and Kinetic Transport in 1D). The framework can handle systems of non-linear ODEs, various 1D PDEs arising in fluid modelling, as well as PDEs arising from the treatment of the electron kinetic equation. As such, the framework allows for flexibility in fluid models of the Scrape-Off Layer while allowing the easy addition of kinetic electron effects. We focus on presenting both the high-level design decisions that allow for model flexibility, as well as the most important implementation aspects. A significant number of verification and performance tests are presented, as well as a step-by-step walkthrough of a simple example for setting up models using the Python interface. Program summaryProgram title: ReMKiT1DCPC Library link to program files:https://doi.org/10.17632/j47ym66xzj.1Developer's repository link:https://github.com/ukaea/ReMKiT1D and https://github.com/ukaea/ReMKiT1D-PythonLicensing provisions: GPLv3Programming language: Fortran, PythonSupplementary material:https://doi.org/10.14468/fdq7-z869Nature of problem: The flexible generation and modification of 1D models pertaining to multi-fluid simulations of the tokamak Scrape-Off Layer (SOL) with electron kinetics and reaction support. This would then allow both for rapid iteration on reduced models as well as the evaluation of kinetic electron effects in equilibria and during transients, following the formalism previously developed for SOL-KiT [1]. The framework was not only envisioned as the successor to SOL-KiT, but a tool that would allow users to construct their own models coupled with electron kinetics capabilities.Solution method: The framework is written heavily utilizing Object-Oriented design principles, in particular using an extended version of the puppeteer pattern as presented by Rouson et al. [2], as well as the heavy use of the strategy pattern/dependency injection. The Fortran code is MPI parallel and utilizes the PETSc library for implicit time-stepping. MPI parallelization is extended to distribution function Legendre harmonics, allowing for improved strong scaling. Initialization of the Fortran framework is done using JSON configuration files generated by an accompanying Python interface, and data analysis is standardized using widely used data formats such as HDF5.Additional comments including restrictions and unusual features: The present manuscript focuses on the design and high-level implementation of the framework, as well as the demonstration of the workflow and various verification and performance benchmarking tests. Some details are avoided for the sake of brevity at various points, and these are meant to be available as part of the general code documentation or tutorials offered on the main repositories.

Surface functionalization of calcium magnesium phosphate cements with alginate sodium for enhanced bone regeneration via TRPM7/PI3K/Akt signaling pathway

Although calcium‑magnesium phosphate cements (CMPCs) have been widely applied to treating critical-size bone defects, their repair efficiency is unsatisfactory owing to their weak surface bioactivity and uncontrolled ion release. In this study, we lyophilized alginate sodium (AS) as a coating onto HAp/K-struvite (H@KSv) to develop AS/HAp/K-struvite (AH@KSv), which promotes bone regeneration. The compressive strength and hydrophilicity of AH@KSv significantly improved, leading to enhanced cell adhesion in vitro. Importantly, the SA coating enables continuous ions release of Mg2+ and Ca2+, finally leading to enhanced osteogenesis in vitro/vivo and different patterns of new bone ingrowth in vivo. Furthermore, these composites increased the expression levels of biomarkers of the TRPM7/PI3K/Akt signaling pathway via an equilibrium effect of Mg2+ to Ca2+. In conclusion, our study provides novel insights into the mechanisms of Mg-based biomaterials for bone regeneration.

A Theory of Small Campaign Contributions

Abstract Popular and academic discussions have mostly concentrated on large donors, even though small donors are a major source of financing for political campaigns. We propose a theory of small donors with a key novelty: it centres on the interactions between small donors and the parties’ fundraising strategy. In equilibrium, parties micro-target donors with a higher contribution potential (that is, richer and with more intense preferences) and increase their total fundraising effort in close races. The parties’ strategic fundraising amplifies the effect of income on contributions, and leads to closeness, underdog and bandwagon effects. We then study the welfare effects of a number of common campaign finance laws. We find that, due to equilibrium effects, those tools may produce outcomes opposite to intended objectives. Finally, we identify a tax-and-subsidy scheme that mutes the effect of income while still allowing donors to voice the intensity of their support.

Migration and the environment: A look across perspectives

The decisions related to migration – where to live, when to move, and where to move – have a long history in economics. Different fields, within economics and outside economics, have developed different empirical methods to study migration and its consequences. However, these literatures rarely cite each other and there is little crossover between them. The purpose of this paper is twofold. First, to provide a simple theoretical framework for understanding general equilibrium effects in migration models that can help researchers think through the specific contexts in which these will be a problem for reduced form estimation. Second, to examine the different literatures in economics that have addressed the question of the effects of environmental amenities on migration with an eye to the differences across them and the way they can complement each other.

Microcredit: equilibrium effects

Abstract Changes to access to credit can potentially cause changes to the returns to various factors—general equilibrium (GE) effects. This paper considers changes in wages, prices of goods and services, interest rates, and in the returns to forming or maintaining social ties. Such GE effects can lead to positive and/or negative indirect effects on economic agents, including those who are not directly affected by a given credit policy. Thus such effects matter for the average level and distribution of impacts resulting from credit access. In addition, GE effects have implications for research design, in that those who are indirectly affected via GE channels are generally not a valid counterfactual for those who are directly affected.

Searching for NLTE effects in the high-resolution transmission spectrum of WASP-121 b with cloudy for exoplanets

ABSTRACT Ultrahot Jupiters (UHJs) undergo intense irradiation by their host stars and are expected to experience non-local thermodynamic equilibrium (NLTE) effects in their atmospheres. Such effects are computationally intensive to model but, at the low pressures probed by high-resolution cross-correlation spectroscopy (HRCCS), can significantly impact the formation of spectral lines. The UHJ WASP-121 b exhibits a highly inflated atmosphere, making it ideal for investigating the impact of NLTE effects on its transmission spectrum. Here, we formally introduce cloudy for exoplanets, a cloudy-based modelling code, and use it to generate 1D LTE and NLTE atmospheric models and spectra to analyse archival HARPS WASP-121 b transmission spectra. We assessed the models using two HRCCS methods: (i) Pearson cross-correlation, and (ii) a method that aims to match the average observed line depth for given atmospheric species. All models result in strong detections of Fe i (7.5 < S/N < 10.5). However, the highest S/N model (LTE) does not agree with the best-matching model of the average line depth (NLTE). We also find degeneracy, such that increasing the isothermal temperature and metallicity of the LTE models can produce average line depths similar to cooler, less metal rich NLTE models. Thus, we are unable to conclusively remark on the presence of NLTE effects in the atmosphere of WASP-121 b. We instead highlight the need for standardized metrics in HRCCS that enable robust statistical assessment of complex physical models, e.g. NLTE or 3D effects, that are currently too computationally intensive to include in HRCCS atmospheric retrievals.

Effect of equilibrium and non-equilibrium sediment transport flows on the shear velocity in an open channel.

Equilibrium and non-equilibrium sediment transport flow in natural rivers and artificial channels can result in degradation or aggradation of the river bed, which will affect many hydraulic parameters, one of which is shear velocity. This study evaluates the influence of sediment transport on shear velocity in open channels. In this study, laboratory experiments were carried out using a sediment-recirculating flume, and measurements of the velocity and Reynolds shear stress distributions were measured using a Sontek-acoustic Doppler velocimeter (ADV). This experimental study measured 120 velocity distributions, and Reynolds stress profiles, consisting of 12 different sets of measurements involving flow with sediment transport and movable sand bed. The results showed an average shear velocity, u*, difference between sediment feeding and without sediment feeding by 9.41%. For the integration constant Br value, the average difference between sediment feeding and without sediment feeding was 5.58%.

Intrinsic correlation between the generalized phase equilibrium condition and mechanical behaviors in hydrate-bearing sediments

The phase equilibrium and mechanical behaviors of natural gas hydrate-bearing sediment are essential for gas recovery from hydrate reservoirs. In heating closed systems, the temperature-pressure path of hydrate-bearing sediment deviates from that of pure bulk hydrate, reflecting the porous media effect in phase equilibrium. A generalized phase equilibrium equation was established for hydrate-bearing sediments, which indicates that both capillary and osmotic pressures cause the phase equilibrium curve to shift leftward on the temperature-pressure plane. In contrast to bulk hydrate, hydrate-bearing sediment always contains a certain amount of unhydrated water, which keeps phase equilibrium with the hydrate within the hydrate stability field. With changes in temperature and pressure, a portion of pore hydrate and unhydrated water may transform into each other, affecting the shear strength of hydrate-bearing sediment. A shear strength model is proposed to consider not only hydrate saturation but also the change in temperature and pressure of hydrate-bearing sediment. The model is validated by experimental data with various hydrate saturation, temperature and pressure conditions. The deformation induced by partial dissociation was studied through depressurization tests under constant effective stress. The reduction in gas pressure within the hydrate stability field indeed caused sediment deformation. The dissociation-induced deformation can be reasonably estimated as the difference in volume between hydrate-bearing and hydrate-free sediments from the compression curves.

Dynamic control of DNA condensation

Artificial biomolecular condensates are emerging as a versatile approach to organize molecular targets and reactions without the need for lipid membranes. Here we ask whether the temporal response of artificial condensates can be controlled via designed chemical reactions. We address this general question by considering a model problem in which a phase separating component participates in reactions that dynamically activate or deactivate its ability to self-attract. Through a theoretical model we illustrate the transient and equilibrium effects of reactions, linking condensate response and reaction parameters. We experimentally realize our model problem using star-shaped DNA motifs known as nanostars to generate condensates, and we take advantage of strand invasion and displacement reactions to kinetically control the capacity of nanostars to interact. We demonstrate reversible dissolution and growth of DNA condensates in the presence of specific DNA inputs, and we characterize the role of toehold domains, nanostar size, and nanostar valency. Our results will support the development of artificial biomolecular condensates that can adapt to environmental changes with prescribed temporal dynamics.

Physicochemical and emulsification properties of okara-derived soluble dietary fiber modified by steam explosion

The effective utilization of by-products still poses a challenge in the food industry. In this work, soluble dietary fiber (SDF) extracted from okara was modified by steam explosion (SE) via adjusting steam pressure (1.0, 1.5, and 2.0 MPa) and SE duration (60 and 120 s). The structural and emulsification properties of modified SDF were studied. The untreated SDF exhibited a low yield (5.17%) and poor emulsification properties due to its large molecular weight (162.67 kDa), compact structure, and high interfacial tension (14.27 mN/m). SE increased SDF content by a maximum of 30.31%, 4.86 times higher than that of untreated SDF. Under mild SE conditions (1.0 MPa for 60 s), SDF displayed a loose structure with abundant side chains and a higher glyoxylate content (26.77%). Its near-neutral contact angle (82.0°) and lower interfacial tension (12.69 mN/m) endowed it with higher emulsification capacity, smaller emulsion droplet size, and enhanced emulsifying stability. The molecular weight of SDF decreased and the specific surface area enlarged with increasing SE intensity. Notably, SDF exhibited the best interfacial adsorption characteristics under SE of 2.0 MPa for 120 s, attributed to its low molecular weight (46.99 kDa) and higher protein content (7.58%). Overall, the improved emulsification properties of SDF were attributed to the synergistic effects of amphiphilic equilibrium, electrostatic repulsion, spatial resistance, and enhanced droplet-to-droplet interactions.

Detection of Tidally Excited Oscillations in Kepler Heartbeat Stars

Heartbeat stars (HBSs) with tidally excited oscillations (TEOs) are ideal laboratories for studying the effect of equilibrium and dynamical tides. However, studies of TEOs in Kepler HBSs are rare due to the need for better modeling of the equilibrium tide in light curves. We revisit the HBSs in our previous work and study the TEOs in these HBSs based on the derived orbital parameters that could express the equilibrium tide. We also compile a set of analytic procedures to examine the harmonic and anharmonic TEOs in their Fourier spectra. The TEOs of 21 HBSs have been newly analyzed and presented. Twelve of these HBSs show prominent TEOs (signal-to-noise ratio of the harmonics S/N ≥ 10). The relation between the orbital eccentricities and the harmonic number of the TEOs shows a positive correlation. The relation between the orbital periods and the harmonic number also shows a positive correlation. Furthermore, the distribution of HBSs with TEOs in the Hertzsprung–Russell diagram shows that TEOs are more visible in hot stars with surface effective temperatures T ≳ 6500 K. These samples may also be valuable targets for future studies of the effect of tidal action in eccentric orbits.

Episodic hydrothermal alteration on Middle Permian carbonate reservoirs and its geological significance in southwestern Sichuan Basin, SW China

To analyze the episodic alteration of Middle Permian carbonate reservoirs by complex hydrothermal fluid in southwestern Sichuan Basin, petrology, geochemistry, fluid inclusion and U-Pb dating researches are conducted. The fractures and vugs of Middle Permian Qixia–Maokou formations are filled with multi-stage medium−coarse saddle dolomites and associated hydrothermal minerals, which indicates that the early limestone/dolomite episodic alteration was caused by the large-scale, high-temperature, deep magnesium-rich brine along flowing channels such as basement faults or associated fractures under the tectonic compression and napping during the Indosinian. The time of magnesium-rich hydrothermal activity was from the Middle Triassic to the Late Triassic. The siliceous and calcite fillings were triggered by hydrothermal alteration in the Middle and Late Yanshanian Movement and Himalayan Movement. Hydrothermal dolomitization is controlled by fault, hydrothermal property, flowing channel and surrounding rock lithology, which occur as equilibrium effect of porosity and permeability. The thick massive grainstone/dolomites were mainly altered by modification such as hydrothermal dolomitization/recrystallization, brecciation and fracture-vugs filling. Early thin–medium packstones were mainly altered by dissolution and infilling of fracturing, bedding dolomitization, dissolution and associated mineral fillings. The dissolved vugs and fractures are the main reservoir space under hydrothermal conditions, and the connection of dissolved vugs and network fractures is favorable for forming high-quality dolomite reservoir. Hydrothermal dolomite reservoirs are developed within a range of 1 km near faults, with a thickness of 30–60 m. Hydrothermal dolomite reservoirs with local connected pore/vugs and fractures have exploration potential.

One-step in-situ fabrication of novel food-grade Janus droplets with zein and alginate: Dual effect of phase separation and interfacial equilibrium

Janus droplets exhibit an asymmetric structure, where one droplet has two compartments with different properties. However, food-grade Janus droplets are rarely reported. In this work, food-grade Janus droplets composed of alcohol-soluble protein and alginate were fabricated for the first time by the one-step in-situ method. Segregative phase separation and interfacial equilibrium of zein and alginate solutions were the prerequisites for the formation of food-grade Janus droplets. Segregative phase separation occurred when the concentration of zein and alginate solutions was increased. The zein in the aqueous phase synergistically reduced the oil-water interfacial tension with polyglycerol polyricinoleate (PGPR), but the alginate weakened the interfacial ability of PGPR, resulting in an increase of oil-water interfacial tension. Therefore, the interfacial tension difference between zein/oil and alginate/oil could be regulated by changing the concentration of zein and alginate solutions, which was beneficial to the interfacial equilibrium. The droplet size of food-grade Janus droplets could be adjusted by the concentrations of zein and alginate solutions. In addition, the Janus droplet structure could be further controlled by the volume ratio of zein and alginate solutions. The destabilization of food-grade Janus droplets was dominated by coalescence and sedimentation. The construction of food-grade Janus droplets is expected to provide a structural basis for the construction of food-grade Janus particles and promote the development of food technology.