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Under the locational marginal price （LMP） mechanism， there are variations in the congestion cost settlement mechanisms among pilot provinces， requiring a comprehensive analysis. To address this， the paper first delves into the essence of the issue by elucidating the connotations of relevant congestion terms； subsequently， based on a unified connotation， it conducts a comparative analysis of the key similarities and differences in the congestion cost settlement mechanisms among typical spot markets in the pilot provinces. Finally， the paper analyzes issues such as user-side settlement point price calculation， charging of congestion fees for medium to long-term contracts， and the allocation of congestion surplus. In conclusion， it presents relevant recommendations.

Given the huge calculation burden and long-time consumption of the existing point-to-point feasible region search method， a new analytical modeling method of feasible regions for power generation is proposed in this paper. Firstly， the construction process of feasible regions for power generation under cross-section safety constraints is introduced， and the boundary characteristics of the feasible regions are analyzed. Secondly， it is deduced mathematically that there is a linear relationship between the output of sensitive generators and the system load at the boundary of the feasible region. An analytical modeling method for the feasible region boundary is proposed based on the linear relationship. Afterwards， when the output power of balanced generators exceeds their limits， a piecewise linear modeling method for the feasible region boundary is introduced. Finally， with a provincial power grid as an example， the feasible region boundary under different cross-section safety constraints is calculated， and the effectiveness of the proposed method is verified through comparison with the existing point-by-point search method.

Objective To explore the value of preoperative LAR combined with AFP in evaluating the prognosis of patients with HCC. Methods We retrospectively analyzed the clinical data of 106 patients with HCC. Kaplan-Meier method was used to draw the survival curve. Univariate analysis was used to analyze possible variables affecting LAR. Cox risk regression model was used to evaluate the clinical value of preoperative LAR and AFP on the prognosis of HCC patients. Results The DFS and OS of the high LAR group and the high AFP group were shorter than those of the low LAR group and the low AFP group (P < 0.05). LAR≥4.58, AFP≥400μg/L and T3-T4 were independent risk factors affecting DFS and OS of HCC patients (P < 0.05). Postoperative interventional surgery was an independent factor influencing OS prolongation (P < 0.05). The DFS and OS were the shortest in the high LAR and high AFP group, and the DFS and OS were the longest in the low LAR and low AFP group (P < 0.05). Conclusion Preoperative LAR and AFP are independent poor prognostic factors of HCC. Preoperative LAR combined with AFP has a certain value in judging the prognosis of HCC patients.

Despite the rapid development of urban rail transit in China, there are still some problems in train operation, such as low efficiency and poor punctuality. To realize a proper allocation of passenger flows and increase train frequency, this paper has proposed an improved urban rail transit scheduling model and solved the model with an adaptive fruit fly optimization algorithm (AFOA). For the benefits of both passengers and operators, the shortest average waiting time of passengers and the least train frequency are chosen as the optimization objective, and train headway is taken as the decision variable in the proposed model. To obtain higher computational efficiency and accuracy, an adaptive dynamic step size is built in the conventional FOA. Moreover, the data of urban rail transit in Zhengzhou was simulated for case study. The comparison results reveal that the proposed AFOA exhibits faster convergence speed and preferable accuracy than the conventional FOA, particle swarm optimization, and bacterial foraging optimization algorithms. Due to these superiorities, the proposed AFOA is feasible and effective for optimizing the scheduling of urban rail transit.

Endothelial dysfunction is an independent risk factor for stroke. The dysfunction of endothelial cells (EC) is closely concerned with EC senescence. Gastrodin (GAS) is an organic compound extracted from the dried root mass of the Orchidaceae plant Gastrodiae gastrodiae. It is used clinically to treat diseases such as vertebrobasilar insufficiency, vestibular neuronitis and vertigo. In the present study, we used hydrogen peroxide (H2O2)‐induced human umbilical vein endothelial cells (HUVECs) to establish an in vitro EC senescence model and to investigate the role and mechanism of GAS in EC senescence. It's found that H2O2‐treated HUVECs increased the proportion of senescence‐associated β‐galactosidase (SA β‐gal) positive cells and the relative protein expression levels of senescence‐associated cyclin p16 and p21. In addition, GAS reduced the proportion of SA β‐gal positive cells and the relative protein expression levels of p16 and p21, and increased the proliferation and migration ability of HUVECs. Meanwhile, GAS increased the expression of the anti‐oxidative stress protein HO‐1 and its nuclear expression level of Nrf2. The anti‐senescence effect of GAS was blocked when HO‐1 expression was inhibited by SnPPIX. Furthermore, absence of HO‐1 abolished the effect of GAS on HUVEC proliferation and migration. In conclusion, GAS ameliorated H2O2‐induced cellular senescence and enhanced cell proliferation and migration by enhancing Nrf2/HO‐1 signalling in HUVECs. These findings of our study expanded the understanding of GAS pharmacology and suggested that GAS may offer a potential therapeutic agent for stroke. [ABSTRACT FROM AUTHOR]

Angiogenesis after ischemic stroke has important clinical significance, which stimulates endogenous recovery mechanisms and improves the neurological outcome. Enhancing angiogenesis may facilitate the function recovery from ischemic stroke. Recent studies have shown that aberrant expression of long noncoding RNAs (lncRNAs) is related to angiogenesis after ischemic stroke. Snhg1, a cancer-related lncRNA, has been reported to be upregulated after stroke. However, little is known about its role in stroke. In this study, we performed in vitro experiments to investigate the effects of Snhg1 on cell survival and angiogenesis and molecular mechanism in ischemic stroke. Oxygen-glucose deprivation/reoxygenation (OGD/R) was used to mimic ischemia/reperfusion injury in vitro. Sngh1 was increased in brain microvascular endothelial cells (BMECs) with the prolongation of exposure to OGD, and promoted BMEC survival under OGD/R condition, and angiogenesis after OGD/R treatment. miR-199a was identified and validated to be a direct target of Snhg1, and function effects of Snhg1 on BMEC survival and angiogenesis depended on miR-199a, which is involved in the regulation of hypoxia inducible factor and vascular endothelial cell growth factor expression. These findings contribute to a better understanding of the pathogenesis of ischemic stroke and facilitate the development of proangiogenesis therapy for this disease. Key words: ischemic stroke, angiogenesis, LncRNA Snhg1, miR-199a. L'angiogenese survenant apres un AVC ischemique revet une signification clinique importante, avec une stimulation de modes d'action endogenes du retablissement et une amelioration des resultats sur le plan neurologique. L'amplification de l'angiogenese pourrait permettre de faciliter le retablissement du fonctionnement apres un AVC ischemique. De recentes etudes ont montre que l'expression anormale de brins d'ARN longs non codants (ARNlnc) est liee a l'angiogenese apres un AVC ischemique. On a rapporte que le Snhg1, un ARNlnc lie au cancer, est regule a la hausse apres un AVC. On sait cependant peu de choses sur son role dans l'AVC. Dans ces travaux, nous avons effectue des experiences in vitro pour etudier les effets du Snhg1 sur la survie cellulaire et l'angiogenese, ainsi que les modes d'action moleculaires dans l'AVC ischemique. Nous avons utilise un modele de privation d'oxygene et de glucose avec reoxygenation (POG/R) en vue de mimer in vitro des lesions d'ischemie/ reperfusion (I/R). Nous avons observe une augmentation des taux de Sngh1 dans les cellules endotheliales microvasculaires du cerveau (CEMC) avec la prolongation de la POG, et une augmentation du taux de survie des CEMC sous POG/R, puis de l'angiogenese apres la POG/R. Nous avons etabli et valide que le miR-199a constitue une cible directe du Snhg1, et que les effets fonctionnels du Snhg1 sur le taux de survie des CEMC dependaient du miR-199a, lequel jouait un role dans la regulation de l'expression du HIF-1[alpha] (pour << hypoxia inducible factor >>) et du VEGF (pour << vascular endothelial cell growth factor >>). Ces resultats permettent de mieux comprendre la pathogenese de l'AVC ischemique et participent au developpement de medicaments facilitant l'angiogenese dans cette maladie. [Traduit par la Redaction] Mots-cles : AVC ischemique, angiogenese, ARN long non codant de Snhg1, miR-199a., Introduction Ischemic stroke is the leading cause of long-term disability and death in the world. Despite great efforts on developing medical and endovascular recanalization therapy, effective treatments for ischemic stroke [...]