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In recent years, the deployment of high-voltage direct current (HVDC) tie-lines in power grids has become a prevalent solution in some countries to transmit renewable energy from remote locations to load centers. However, the variability and uncertainty associated with renewable energy generation pose challenges to effectively utilizing this technology. This work proposes a novel multistage planning-operation model, aiming to unlock the potential flexibility in the HVDC transmission system and increase the renewable penetration. By incorporating flexibility, which is essential for accommodating the uncertainty in renewable generation, our model optimally shares the inter-regional flexibility between the sending- and receiving-end grids. One of the key features of our proposed model is its robustness and non-anticipativity, meaning it can account for different levels of uncertainty and make decisions that are suitable for multiple scenarios. This work develops two solution approaches to solve this challenging multistage model with variable uncertainty sets. We validate the proposed approach through a case study conducted on a real-world inter-regional grid. The numerical results demonstrate that our approach effectively unlocks more inter-regional flexibility and assists in increasing the renewable hosting capacity. [ABSTRACT FROM AUTHOR]

Summary: Phosphorus (P) fertilization can alleviate a soil P deficiency in grassland ecosystems. Understanding plant functional traits that enhance P uptake can improve grassland management.We measured impacts of P addition on soil chemical and microbial properties, net photosynthetic rate (Pn) and nonstructural carbohydrate concentrations ([NSC]), and root P‐uptake rate (PUR), morphology, anatomy, and exudation of two dominant grass species: Leymus chinensis (C3) and Cleistogenes squarrosa (C4).For L. chinensis, PUR and Pn showed a nonlinear correlation. Growing more adventitious roots compensated for the decrease in P transport per unit root length, so that it maintained a high PUR. For C. squarrosa, PUR and Pn presented a linear correlation. Increased Pn was associated with modifications in root morphology, which further enhanced its PUR and a greater surplus of photosynthate and significantly stimulated root exudation (proxied by leaf [Mn]), which had a greater impact on rhizosheath micro‐environment and microbial PLFAs.Our results present correlations between the PUR and the Pn of L. chinensis and C. squarrosa and reveal that NSC appeared to drive the modifications of root morphology and exudation; they provide more objective basis for more efficient P‐input in grasslands to address the urgent problem of P deficiency. [ABSTRACT FROM AUTHOR]

The aim of this study was to screen out the active ingredients of Yuanhu Zhitong prescription (YZP) before and after vinegar processing to play an anti‐alcoholic gastric ulcer role through spectrum‐effect relationship. First, the fingerprint of 16 batches of YZP was studied using the ultra‐high‐performance liquid chromatography‐quadrupole mass spectrometry detector analysis (UPLC‐QDA) method. Second, gastric lesion was induced by anhydrous ethanol. The degree of gastric mucosa injury was evaluated by hematoxylin and eosin staining, and the contents of malondialdehyde and tumor necrosis factor α and superoxide dismutase were detected using the enzyme‐linked immunosorbent assay kit. Sixteen batches of YZP were analyzed using the spectrum‐effect relationship method. Finally, absorption, distribution, metabolism, and excretion (ADME) was used to evaluate the bioavailability of potential compounds. The results showed that the UPLC‐QDA method could successfully establish the fingerprint of YZP. Hematoxylin and eosin staining and biochemical indicators showed that YZP had obvious anti‐alcoholic gastric ulcer action. Coptisine chloride, corydaline, berberine chloride, palmatine, imperatorin, and phellopterin were screened out using the spectrum‐effect method, and all of them possessed good bioavailability. The results of this study suggest that YZP plays an anti‐ulcer role by exerting antioxidant and anti‐inflammatory effects through six main active components. [ABSTRACT FROM AUTHOR]