Search

This research was designed to ascertain the function of euchromatic histone lysine methyltransferase 2 (EHMT2) in ischemic stroke-induced neuronal damage and inflammatory response and its regulatory mechanism.

Reasonable evaluation of evapotranspiration (ET) is crucial for optimizing agricultural water resource management. In the study, we utilized the Data Mining Sharpener (DMS) model; the Landsat thermal infrared images were sharpened from a spatial resolution of 100 m to 30 m. We then used the Surface Energy Balance System (SEBS) to estimate daily ET during the winter wheat growing season in the People's Victory Irrigation District in Henan, China. It was concluded that the spatiotemporal patterns of land surface temperature and daily evapotranspiration remained consistent before and after sharpening. Results showed that the R2 value between the ET of 30 m spatial resolution and the value by eddy covariance method reached 0.814, with an RMSE of 0.516 mm and an MAE of 0.245 mm. All of these were higher than those of 100 m spatial resolution (R2 was 0.802, the RMSE was 0.534 mm, and the MAE was 0.253 mm). Furthermore, the daily ET image with a 30 m spatial resolution exhibited clear texture and distinct boundaries, without any noticeable mosaic effects. The changes in surface temperature and ET were more consistent in complex subsurface environments. The daily evapotranspiration of winter wheat was significantly higher in areas with intricate drainage systems compared to other regions. During the early growth stage, daily evapotranspiration decreased steadily until the overwintering stage. After the greening and jointing stages, it began to increase and peaked during the sizing period. The correlation between net solar radiation and temperature with ET was significant, while relative humidity and soil moisture were negatively correlated with ET. Throughout the growth period, net solar radiation had the greatest effect on ET. [ABSTRACT FROM AUTHOR]

Wellbores drilled in igneous formation with weak interlayers face significant risk of instabilities. This study aims to investigate the underlying mechanisms of these instabilities by employing a combination of rock mechanics tests and numerical simulation techniques. The mechanical properties of igneous rocks are evaluated to determine core strength parameters and analyze the impact of drilling fluid immersion on core strength. The two-dimensional model of the igneous formation is refined, and theoretical derivations are made, including the linear elasticity principal equation and the extent of the plastic zone within the wellbore. A numerical simulation model is developed using ABAQUS to analyze the wellbore stability of the weak interlayer igneous formation, accounting for drilling fluid immersion and weak interlayer conditions. The numerical simulations focus on four key aspects of the weak interlayer formation: strength, permeability, horizontal in-situ stress anisotropy, and abnormal pore pressure. The study findings indicate that strengthening the weak interlayer effectively mitigates the risk of wellbore instability. Moreover, the permeability of the weak interlayer exhibits minimal impact on wellbore stability within the formation. However, an increase in horizontal in-situ stress anisotropy and the abnormal pore pressure both decrease wellbore stability along the direction of the maximum in-situ stress. [ABSTRACT FROM AUTHOR]

In this article, a new double-tapered rectangular tube (DTRT) with diaphragms is introduced as an energy absorber. The material tensile test and impact test were performed to verify the finite element model (FEM) of the tube. Based on the FEM, the Box–Behnken design (BBD) was applied to study the effects of diaphragm geometry on energy absorption (EA) and specific energy absorption (SEA). The weld length between the diaphragm and tube wall has positive effects on the EA and SEA of the DTRT, whereas the hole size on the diaphragms has negative effects. The optimal solution improved the EA and SEA by 12.01% and 9.29%, respectively. The conclusions of this study are based on engineering practice and are expected to aid engineers in designing the diaphragms of tubes as energy-absorbing structures. [ABSTRACT FROM AUTHOR]

A double-tapered rectangular tube with diaphragms (DTRTD) for energy absorbance in railway vehicles is proposed. The mean crushing force (MCF) of DTRTD was derived. The code LS-DYNA3D (971) was used to build a finite element model, validated using a quasi-static test. The experiment results and numerical simulation indicate the accuracy of the theoretical prediction for the MCF of DTRTD and the regularity and stability of the collapse pattern of this energy-absorbing structure (EAS). To explore the effects of the thickness of different EAS parts on the crashworthiness indexes and obtain the optimal designs, the design of experiment (DOE) and a surrogate model were employed for a parameter study and multi-objective optimisation (MOO). The specific energy absorption (SEA) and crush force efficiency (CFE) cannot reach the optimal values concurrently. Nonetheless, all designs from the Pareto front of MOO significantly improve the crashworthiness of EAS because of the larger SEA and CFE. [ABSTRACT FROM AUTHOR]

(Background and objective) Evapotranspiration from managed and natural ecosystems is an important process in hydrological cycle but not trivial to measure at large scales. The eddy covariance developed over the past decade is a technique to measure atmospheric turbulent fluxes which can be used to estimate evapotranspiration and fluxes of other gases. Calculating evapotranspiration from the measurements of eddy covariance is complicated, and the aim of this paper is to experimentally investigate the areas in a farmland system that contribute to the fluxes measured from an eddy covariance. (Method) Atmospheric fluxes were measured from October 2019 to June 2020 using the closed-path eddy covariance system installed in a winter wheat field at Xinxiang comprehensive experimental station in Henan province. Distribution and variation of the measured flux sources were analyzed using the footprint models and FFP and KM methods. (Result) 1 Southwest-northeast wind was the dominant wind during the experimental period, following by northeast-southwest wind. 2 The results calculated under different growth stages and atmospheric conditions revealed that the areas that contributed to the fluxes measured from the device were larger under stable atmospheric conditions than under less stable atmospheric conditions. The direction and length of the areas were affected by wind direction and speed. 3 The results calculated by the FFP and KM models showed a linear relationship between the source areas with SKM=0.93SFFP-1962.5 and R&#178=0.96, and that, in the general, the areas calculated by the KM method were greater than that calculated by the FFP model. (Conclusion) The flux source areas calculated by the FFP and KM methods differed, and the wind direction and speed were the main factors affecting the flux source distribution. For our experiment, the winter wheat was the main contributor to the fluxes measured from the eddy covariance system. [ABSTRACT FROM AUTHOR]

Comprehensive Summary We present a facile synthetic strategy to create mesoporous Cu2O nanocrystals with tunable pore structures and surface functional groups of amine derivatives for efficient and preferable electrochemical conversion of CO2 into ethylene. The structural characteristics of these Cu2O nanocrystals can be manipulated using a set of amine derivatives, such as pyridine, 4,4'‐bipyridine, and hexamethylenetetramine, during the oxidative etching process of Cu nanocrystals by bubbling gaseous oxygen in N,N‐dimethylformamide solution. These amine derivatives not only serve as surface functional groups but also significantly affect the resulting pore structures. The synergistic effect of pore structure confinement and surface amine functionalization leads to the superb Faradaic efficiency (FE) of 51.9% for C2H4, respectively, together with the C2H4 partial current density of –209.4 mA·cm−2 at –0.8 V vs. reversible hydrogen electrode (RHE). The relatively high selectivity towards C2H4 was investigated using DFT simulations, where 4,4'‐bipyridine functionalized Cu2O seemed to favor the C2H4 formation with the low free energy of the intermediates. This study provides a feasible strategy to manipulate the pore structure and surface functionalization of mesoporous Cu2O nanocrystals by regulating the oxidative etching process, which sheds light on the rational preparation of high‐performance CO2RR electrocatalysts. [ABSTRACT FROM AUTHOR]

Benzbromarone (BNR) is prescribed for the management of hyperuricemia, whereas glimepiride (GLM) for the treatment of Type 2 Diabetes Mellitus. Both drugs are certified to be mainly metabolized via cytochrome P450 (CYP) 2C9 in vivo and may have the potential drug-drug interactions. This study aims to investigate the possible influence of orally administered low- and high-dose glimepiride (GLM) on pharmacokinetic characteristics (PK) of benzbromarone (BNR) in rats. Fifteen rats were randomly assigned to group A, B and C (n=5) and administered 0.5% sodium carboxymethyl cellulose (CMC), 0.5mg/kg GLM (low-dose) and 1.0 mg/kg GLM (high-dose) once daily for 8 days, respectively, which were all followed with a single oral dose of BNR (9.0 mg/kg) on the day 8th. Blood samples were obtained from retro orbital plexus at the time points of 0.25, 0.5, 1, 2, 4, 6, 8, 10, 12 and 24h and BNR in plasma was quantitated by HPLC-MS/MS assay. Resultantly a slight influence of GLM on PK of BNR could be found in rats. When compared with Group A, the half-life time (t1/2z) of BNR in Group B and C significantly decreased 52.39% and 73.49%, respectively, although other major PK parameters were negligibly changed by co-administration of GLM. On the whole, the combinational therapy of GLM at low or high dose would notably alter the elimination of BNR and the effect was dose-dependent.