Search

Complex terrain features such as mountains and hills can obstruct the airflow and force upward motion, thereby altering local atmospheric circulation patterns. During the rainy season, these terrain characteristics are more prone to causing intense local precipitation, leading to geological hazards such as floods and debris flows. These phenomena are closely linked to the intricate influence of terrain on wind fields, highlighting the necessity for in-depth research into wind field characteristics under complex terrain conditions. To address this, we propose a neural-network-based model leveraging terrain data and horizontal wind speed data to predict atmospheric motion characteristics and terrain uplift effects in specific terrain conditions. To enhance the generalization ability of the model, we innovatively extract key physical information from the horizontal wind vector data as training parameters. By comparing with the results of the Fluent model, we validate the model's capability in dynamic downscaling and flow field modeling. Experimental outcomes demonstrate that our model can generate terrain-adapted convective warning data with a high accuracy, even when terrain features are altered. Under unoptimized conditions, the results at a maximum resolution of 50 m require only 26 s, and the computation time can be further reduced with algorithmic improvements. This research on adaptive wind field modeling under complex terrain conditions holds significant implications for local wind field simulation and severe convective weather forecasting. [ABSTRACT FROM AUTHOR]

Catalytic hydrodeoxygenation of bioderived furans is critically attractive to prepare sustainable fuels. Herein, a novel octanediol-route was developed to produce octane through one-pot conversion of bioderived furans at low temperatures. A 96.6% yield of octane was obtained by catalytic conversion with Pd/C and phosphotungstic acid (HPW). Experimental validation of the novel pathway revealed that octanediol intermediates could be formed through hydrogenolysis of furans before deoxygenation. The spontaneous process of this octanediol-route was thermodynamically confirmed by DFT simulations. In addition, characterization studies suggested that water in the system strengthened the cooperation between metals and acids to facilitate C–O bond scission through the modification and hydrogen transfer of HPW. This work highlights a promising reaction pathway for an efficient HDO catalytic system to obtain alkanes from bioderived furans under mild conditions. [ABSTRACT FROM AUTHOR]

Contrary to current insulin formulations, endogenous insulin has direct access to the portal vein, regulating glucose metabolism in the liver with minimal hypoglycaemia. Here we report the synthesis of an amphiphilic diblock copolymer comprising a glucose-responsive positively charged segment and polycarboxybetaine. The mixing of this polymer with insulin facilitates the formation of worm-like micelles, achieving highly efficient absorption by the gastrointestinal tract and the creation of a glucose-responsive reservoir in the liver. Under hyperglycaemic conditions, the polymer triggers a rapid release of insulin, establishing a portal-to-peripheral insulin gradient-similarly to endogenous insulin-for the safe regulation of blood glucose. This insulin formulation exhibits a dose-dependent blood-glucose-regulating effect in a streptozotocin-induced mouse model of type 1 diabetes and controls the blood glucose at normoglycaemia for one day in non-obese diabetic mice. In addition, the formulation demonstrates a blood-glucose-lowering effect for one day in a pig model of type 1 diabetes without observable hypoglycaemia, showing promise for the safe and effective management of type 1 diabetes., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)