Search

Using the regionally refined mesh (RRM) configuration of the US Department of Energy's Simple Cloud-Resolving Energy Exascale Earth System Model (E3SM) Atmosphere Model (SCREAM), we simulate and evaluate four meteorologically distinct atmospheric river events over California. We test five different RRM configurations, each differing in terms of the areal extent of the refined mesh and the resolution (ranging from 800 m to 3.25 km). We find that SCREAM RRM generally has a good representation of the AR-generated precipitation in CA, even for the control simulation which has a very small 3 km refined patch, and is able to capture the fine-scale regional distributions that are controlled largely by the fine-scale topography of the state. It is found that SCREAM generally has a wet bias over topography, most prominently over the Sierra Nevada mountain range, with a corresponding dry bias on the lee side. We find that refining the resolution beyond 3 km (specifically 1.6 km and 800 m) has virtually no benefit towards reducing systematic precipitation biases but that improvements can be found when increasing the areal extent of the upstream refined mesh. However, these improvements are relatively modest and only realized if the size of the refined mesh is expanded to the scale where employing RRM no longer achieves the substantial cost benefit it was intended for. [ABSTRACT FROM AUTHOR]

The spatial heterogeneity related to complex topography in California demands high-resolution (< 5 km) modeling, but global convection-permitting climate models are computationally too expensive to run multi-decadal simulations. We developed a 3.25 km California climate modeling framework by leveraging regional mesh refinement (CARRM) using the U.S. Department of Energy (DOE)'s global Simple Cloud-Resolving E3SM Atmosphere Model (SCREAM) version 0. Four 5-year time periods (2015–2020, 2029–2034, 2044–2049, and 2094–2099) were simulated by nudging CARRM outside California to 1° coupled simulation of E3SMv1 under the Shared Socioeconomic Pathways (SSP)5-8.5 future scenario. The 3.25 km grid spacing adds considerable value to the prediction of the California climate changes, including more realistic high temperatures in the Central Valley and much improved spatial distributions of precipitation and snowpack in the Sierra Nevada and coastal stratocumulus. Under the SSP5-8.5 scenario, CARRM simulation predicts widespread warming of 6–10 °C over most of California, a 38 % increase in statewide average 30 d winter–spring precipitation, a near-complete loss of the alpine snowpack, and a sharp reduction in shortwave cloud radiative forcing associated with marine stratocumulus by the end of the 21st century. We note a climatological wet precipitation bias for the CARRM and discuss possible reasons. We conclude that SCREAM RRM is a technically feasible and scientifically valid tool for climate simulations in regions of interest, providing an excellent bridge to global convection-permitting simulations. [ABSTRACT FROM AUTHOR]

Exploring the intensive planting scheme to improve the agricultural productivity of coastal salinized farmland, the field positioning trial conducted in Kenli district, Shandong province was carried out since 2015, and 4 treatments were set up by considering fertilizer application amount, fertilizer application period, planting density, soil amendment and other measures including farmer's practice (FP), improved soil management (ISM), improved crops management (ICM), integrated soil crop management (ISCM). Track the population dynamic changes in the key growth period of wheat, analyzed the dry matter accumulation and nitrogen, phosphorus and potassium nutrient absorption of wheat and maize during harvest, investigated the changes of wheat and maize yield and yield components, and compared the net income of crop production, soil sodium removal rate and sodium adsorption ratio in the 0--20 cm soil layer after harvest. The results showed that compared with FP treatment, ISM significantly increased the number of ears during wheat and maize harvest, resulting in a 25.2% and 10.0% increase in yield, and a 7.8% increase in net income, respectively. In addition, the soil sodium removal rate of ISM treatment reached 78.6%. The ICM treatment significantly increased the dry matter accumulation of wheat and maize, with a yield increase of 17.8% and 10.7%, respectively, compared to the FP treatment, and the net income increase of 19.3% . The ISCM treatment obtained the highest wheat yield of 11.96 and 10.83 t · hm-2, respectively, the net income increased by 20.8% compared to the FP treatment, and the soil sodium removal rate reached 82.9%. The ISM treatment could significantly reduce the sodium ion content of salinized soil, improve the nutrient absorption capacity of wheat and maize, and increase yield. Although the yield increase effect of ICM treatment was lower than that of ISM treatment, lower input cost could obtain higher net benefit. On the whole, the ISCM treatment could simultaneously achieve soil quality improvement, crop yield increase and economic benefits, which was the optimal management practice scheme under the conditions of this study. This research result could provide technical and theoretical support and demonstration models for improving the production capacity of medium to low yield fields in the region. [ABSTRACT FROM AUTHOR]

Dark fermentation (DF) is prone to low hydrogen (H 2 ) yield. In this work, magnesium aluminum-layered double hydroxide and carbonized humic acid (MgAl-LDH/CHA) was synthesized by co-precipitation to reveal the mechanism in rising bioH 2 generation. The results indicated that MgAl-LDH released Mg and Al ions slowly in DF system, improving the activity of H 2 -producing microbes (HPM) for more H 2 . The H 2 yield increased from 169.3 mL/g glucose to 244.9 mL/g glucose, which was 44.7 % higher than that for the control yield. MgAl-LDH/CHA increased Proteobacteria content from 30.9 % to 43.7 %, making it form a complex microbial community and participate in DF metabolism with Firmicutes and other microbes together. Besides, MgAl-LDH/CHA could serve as an electron shuttle that likely effectively promotes electron transfer in DF, significantly reduced the energy requirements of HPM, thus raising metabolic activity. It provides direction for the multi-element composite applied in DF system., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Background: In the past, some observational studies have highlighted the correlation between gut microbiota and irritable bowel syndrome (IBS). However, it is still unknown if the composition of gut microbiota shows a causal effect on the risk of IBS., Aim: To conduct Mendelian randomization (MR) analysis of the samples to study the probable causal relationship between the gut microbiota, their taxonomic groups, and the risk of IBS., Materials and Methods: In this study, the summarized data regarding 211 gut microbiota and their IBS genome-wide association studies (GWAS) were collected from public databases. The causal estimates were determined using five MR techniques, where Inverse Variance Weighted (IVW) regression was employed as the major MR technique. Herein, MR-PRESSO and MR-Egger intercept tests were conducted to prevent horizontal pleiotropy. Cochran's Q test was used to evaluate heterogeneity using the IVW and MR-Egger techniques., Results: IVW results showed that gut microbes, belonging to Class Gammaproteobacteria ( P = 0.04; OR = 1.45), Family XIII ( P = 0.03; OR = 1.34), Family Prevotellaceae ( P = 0.003; OR =1.24), and Lachnospiraceae UCG004 ( P = 0.049; OR = 1.19) increased the risk of IBS, while Alcaligenaceae ( P = 0.03; OR = 0.83, 95% CI: 0.69-0.98) and Coprobacter ( P = 0.02; OR = 0.86, 95% CI: 0.76-0.98) decreased the risk of IBS., Conclusions: This study presented novel insights that highlighted the causal relationship between gut microbiota and IBS, and offered new treatment strategies for preventing or treating IBS.