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Train dispatching is critical for the punctuality and reliability of passenger transportation, especially in railway systems with ticketing reservations required. In such a system, e.g., the high-speed railway in China, the service frequency is usually low on most lines, and passengers often have very limited route options (no diversity and flexibility). In the presence of disruptions, e.g., segment blockage, trains services may be canceled due to insufficient infrastructure capacity, which can cause big troubles to passengers since they are very unlikely to find alternative, consequently being stranded. Thus, transporting these stranded passengers becomes the most important but complicated task. In this study, we propose to add extra stops to the running trains, i.e., re-servicing, in order to effectively utilize the reduced capacity of tracks. We identify and formulate the complex relation between track utilization, trains stop adding, and passenger rerouting, based on a time-space network. Local rerouting of trains is represented, and the tracks in each station are categorized by main track (stopping with no passenger activities) and siding track (train passing without a stop is not allowed). An integer linear programming (ILP) model is constructed to solve the integrated problem of train rescheduling and passenger rerouting with the consideration of re-servicing, which includes train cancelation and extra stop adding. Finally, a Lagrangian solution framework is introduced to solve the NP-hard problem, and the method is test on a real-world network of Chinese high-speed railway, conducting several experiments to demonstrate the reasonability, effectiveness, and efficiency of the proposed method.

Background: Menstruation is considered a contraindication for elective surgery for higher operative blood loss. Progesterone is often used to postpone menstruation to avoid surgery during menstruation. This study aimed to explore whether using progesterone to postpone menstruation affects perioperative blood loss in female patients with adolescent idiopathic scoliosis (AIS) who underwent posterior spinal fusion (PSF) surgery. Methods: A retrospective study was performed for female patients diagnosed with AIS who underwent PSF surgery between March 2013 and January 2021. Patients with irregular menstruation or before menarche,who used tranexamic acid, who underwent Schwab grade III–VI osteotomywere excluded. Patients scheduled to undergo PSF surgery from 2 days before menstruation to 3 days after menstruation were treated with progesterone preoperatively. The patients were divided into two groups according to progesterone use (group A, progesterone injection group; group B, control group). Demographic and surgical data including intraoperative blood loss (IBL), normalized blood loss (NBL), total blood loss (TBL), transfusion rate, perioperative complications, postoperative hospital stay,and preoperative coagulation function data. Results:Group A included 41 patients, while group B included 165. The two groups were matched for age, height, weight, operation time, Risser sign, correction rate, mean curve Cobb angle, bending Cobb angle, and number of internal fixations, number of fused levels (all P >0.05). Regarding coagulation function, no significant difference was found between thrombin time, activated partial thromboplastin time, fibrinogen, prothrombin time and platelet count. IBL, NBL and TBL were higher in group A; however, the difference was nonsignificant. Transfusion rate, perioperative complications, and postoperative hospital stay were not statistically different between groups. Conclusion: Intramuscular injection of progesterone to postpone menstruation did not affect perioperative blood loss in female AIS patients who underwent PSF surgery. Furthermore, it did not increase the incidence of perioperative complications or prolong postoperative hospital stay. Therefore, it may be a safe method for AIS patients to undergo PSF surgery as scheduled.

Background.One previous work confirmed that laminar slope angle was associated with the ossification of thoracic ligamentum flavum. Several studies have investigated the relevance of disc degeneration grade, thickness of ligamentum flavum, along with cross section area of multifidus and its fatty infiltration. However, there has been no research between the angle and them. This retrospectivestudyof clinical materials from 122 patients was designed to investigate the influence of laminar slope angle on degeneration of lumbar when eliminating the interference of age.Methods.122 individuals were retrospected randomly on the basis of age difference from 687inpatients scheduled to undergo a lumbar operation between January and December 2017.We registered their age and sex, evaluated and measuredL4-L5 disc degeneration grade,correspondingcross section area of multifidus, muscle-fat index,thickness of ligamentum flavum and laminar slope angle from preoperative magnetic resonance imagingand three-dimensional computer tomography. Independent-sample T tests were used to assess the association between age and measurement indices. The Pearson correlation coefficient, and partial correlation excluding age, was also performed to analyze thecorrelation between clinical parameters.Results.Our results showed that age was positively connected withthe laminar slope angle(L4:r=0.298, p=＜0.01; L5:r=0.303, p=＜0.01). Excluding the interference of age, revealed a credibly negative relationship between the angle of L4 and the thickness of the ligamentum flavum(Left: r=-0.303, p=＜0.01;Right:r=-0.340, p=＜0.01). However, there was no correlationwithother parameters(disc: r=-0.141, p＞0.05; left multifidus: r=0.248, p＞0.05; right multifidus: r=0.225, p＞0.05; left muscle-fat index: r=0.033, p＞0.05; right muscle-fat index: r=0.016, p＞0.05).Conclusion.Excluding the interference of age, Inclination of small laminar slope angle leads to hypertrophy of lumbar ligamentum flavum.LEVEL OF EVIDENCE:Level 4.