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We present real-space dynamical mean-field theory calculations for attractively interacting fermions in three-dimensional lattices with elongated traps. The critical polarization is found to be 0.8, regardless of the trap elongation. Below the critical polarization, we find unconventional superfluid structures where the polarized superfluid and Fulde-Ferrell-Larkin-Ovchinnikov-type states emerge across the entire core region.

This study examines the impact of oil price uncertainty on mergers and acquisition (M&A) activity in the oil and gas sector. Analyzing this industry enables us to construct a natural forward-looking measure of oil price uncertainty, namely the implied crude oil volatility. Using a sample of U.S. firms in the oil and gas sector from 1994–2018 containing 4,323 announced transactions, we document that oil price uncertainty is negatively related to future M&A activity. Uncertainty is mainly a driver of horizontal and vertical M&A activity, where upstream firms are more affected by this uncertainty than downstream firms. Our results lend support to a real options explanation of investment under uncertainty where firms choose to defer investments as a response to increased uncertainty.

Experimental research of photocatalytical oxidation (PCO) of aqueous solutions of de‐icing agents (ethylene glycol and ethylene glycol monoethyl ether) and methyl tert‐butyl ether (MTBE) was undertaken. These chemicals are water‐soluble components of jet and motor fuels accidentally disposed to the environment. Titanium dioxide (Degussa P25) under near‐UV irradiation was selected as a photocatalyst. A slightly acidic medium was preferable for the process efficiency for MTBE, whereas a neutral medium was beneficial for de‐icing agents and jet fuel aqueous extracts. TiO2 suspension fractional composition was found to be dependent on pH and the presence of organic admixtures: the minimum size of TiO2 particles at their maximum uniformity was established in an acidic medium, where the efficiency of PCO of de‐icing agents was the poorest. On the other hand, neutral and slightly acidic media, beneficial for PCO efficiency, were favourable for particle agglomeration, which indicates a minimal role for photocatalyst particle size in PCO efficiency. PCO efficiency increased with increasing MTBE and icing inhibitor concentration. The biodegradability of aqueous solutions of oxygenated additives increased as PCO proceeded. The influence of mineral additives—sulphate, calcium, ferric and manganese ions—on the process efficiency was found to be complex. Special attention was paid to energy‐saving PCO with a photocatalyst attached to buoyant glass micro‐spheres and reduced intensity of stirring of the slurry.

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A model for pressurised steam/O2-blown fluidised-bed gasification of biomass with catalytic reforming of hydrocarbons and tars was developed using Aspen Plus simulation software. Seven main blocks were used to model the fluidised-bed gasifier and two for the catalytic reformer. Modelling blocks were complemented with FORTRAN subroutines to simulate the observed non-equilibrium behaviour of the process. The model was fitted with experimental data derived from a 0.5 MW scale test rig operated with crushed wood pellets and forest residues and was shown to be capable of predicting product gas composition from gasification of clean wood. A parametric analysis indicated that a significant improvement in the syngas efficiency could be achieved by rising the filtration temperature and reformer conversions. Other improvement possibilities include fuel drying and lower reforming temperature.

Abstract Longer term monitoring of soil water content at a catchment scale is a key to understanding its dynamics, which can assist stakeholders in decision making processes, such as land use change or irrigation programs. Soil water monitoring in agriculturally dominated catchments can help in developing soil water retention measurements, for assessment of land use change, or adaptation of specific land management systems to climate change. The present study was carried out in the Pannonian region (Upper-Balaton, Hungary) on Cambisols and Calcisols between 2015 and 2021. Soil water content (SWC) dynamics were investigated under different land use types (vineyard, grassland, and forest) at three depths (15, 40, and 70 cm). The meteorological data show a continuous decrease in cumulative precipitation over time during the study with an average of 26% decrease observed between 2016 and 2020, while average air temperatures were similar for all the studied years. Corresponding to the lower precipitation amounts, a clear decrease in the average SWC was observed at all the land use sites, with 13.4%, 37.7%, and 29.3% lower average SWC for the grassland, forest, and vineyard sites, respectively, from 2016 to 2020 (measured at the 15 cm depth of the soil). Significant differences in SWC were observed between the annual and seasonal numbers within a given land use (p < 0.05). The lowest average SWC was observed at the grassland (11.7%) and the highest at the vineyard (28.3%). The data showed an increasing average soil temperature, with an average 6.3% higher value in 2020 compared to 2016. The grassland showed the highest (11.3 °C) and the forest soil the lowest (9.7 °C) average soil temperatures during the monitoring period. The grassland had the highest number of days with the SWC below the wilting point, while the forest had the highest number of days with the SWC optimal for the plants.

1. Marine Heat Waves (MHWs) are episodes of anomalous warming in the ocean that can last from a few days to months. MHWs have different characteristics in terms of intensity, duration, and frequency and generate thermal stress on marine ecosystems. In reef ecosystems, they are one of the main causes of decreased presence and abundance of corals, invertebrates, and fish. The deleterious capacity of thermal stress often depends upon biotic factors such as resource availability (bottom-up control on predators) and predation (top-down control on prey). Despite the evidence of thermal stress and biotic factors affecting individual species, the combined effects of both stressors on the entire reef ecosystems are far less studied. 2. Here, using a food-web modeling approach, we estimated the rate of change in species’ biomass due to different MHW scenarios based on their physical characteristics. Specifically, we modeled the mechanistic link between species’ consumption rate and seawater temperature (thermal stressor), simulating species’ biomass dynamics for different MHW scenarios under different trophic control assumptions (biotic factor). 3. We find that total reef ecosystem biomass declined by 10% ± 5% under MHWs with severe intensity and top-down control assumption. The bottom-up control assumption moderates the total ecosystem biomass reduction by 5% ± 5%. Irrespective of the MHW scenario and the trophic control assumption, the most substantial biomass changes occur among top, meso-predators, and corals (5% to 20% ± 10%).4. Since habitat degradation may lead to reef ecosystems governed by top-down control on prey, our findings point to the critical importance of protecting reef ecosystems as a pivotal strategy to alleviate the impacts of thermal stress induced by MHWs. Overall, our results provide a unified understanding of the interplay between abiotic stressors and biotic factors in reef ecosystems under extreme thermal events, offering insights into present baselines and future ecological states for reef ecosystems.