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In the live firing of mortar, the base plate is generally constructed at an angle of about 20° with the horizontal ground, so as to make the base plate more stable and improve the shooting accuracy. In order to explore the optimal matching angle between barrel and plate in live firing, a rigid-flexible coupling finite element model of a certain 82 mm mortar and soil is established. The dynamic response of launching is analyzed based on explicit solver under six working conditions with no. 4 charge, angle of fire 50°, angle of fire 60°, plate and horizontal ground 10°, 20° and 30° respectively. The relative change curves of the angle of firing of the first round of mortar under six conditions are obtained. It is found that when other firing conditions are consistent, the closer the angle between the plate and the barrel is to 90°, the smaller the relative change of the firing angle of the mortar is. When the angle between the plate and the barrel is to 90°, the relative change of the firing angle also reaches the minimum value, and the firing accuracy is the highest. The research results have reference value for the reliable use of mortars, the study of launch dynamic response and the design of related auxiliary devices.

Methotrexate (MTX) is characterized as first-line therapy although its indication of ectopic pregnancy is off-label use. We aimed to conduct a retrospective cohort study to investigate the incidence, characteristics of adverse drug reactions (ADRs) of MTX, provide valuable insights for medical workers. Basing on China Hospital Pharmacovigilance System (CHPS), a retrospective analysis was performed to evaluate the safety of MTX (n = 672). An active monitoring model was set to detect ADR signals from the hospital information system. Frequency, Common Terminology Criteria for Adverse Events (CTCAE) grade proportion and association of dose exposure with ADRs were presented as outcomes. The total incidence of ADRs was 54.0%. Anaemia (37.6%) was the most frequent ADR, followed by hepatic function abnormal (11.3%), hyperuricemia (6.1%), neutropenia (4.6%), leukopenia (4.0%), and dyslipidaemia (2.5%). For the composition of all ADRs, CTCAE grade one, two and three dominated for 86.3%, 12.1% and 1.6%, respectively. The severity of hepatic function abnormal was more serious in the two-dose exposed group (p =.021), while other types of ADRs had no statistical or clinical differences. Logistic regression analysis showed the incidence of any ADRs (OR 1.87 [1.31–2.64]; p =.001), hepatic function abnormal (OR 2.75 [1.69–4.48]; p <.001), dyslipidaemia (OR 5.15 [1.87–14.13]; p =.001) were significantly higher in the two-dose exposed group. After adjusted, the positive associations were still maintained. MTX is quite safe in ectopic pregnancy, despite its mild to moderate hematotoxicity, hepatotoxicity and nephrotoxicity. Taking CHPS can present the accurate denominator of the incidence of adverse drug reactions into account, our study advocates that it may have great potential to be used as an active monitoring tool for off-label drug use risk management. [ABSTRACT FROM AUTHOR]

When angular contact ball bearings match together,due to high demand of manufacturing and installation precision,only increasing the number of angular contact ball bearings to increase the radial bearing capacity has great limitations.Therefore,it was considered that using heterogeneous rolling bearing match to increase the radial bearing capacity of bearing match has obvious advantages.Structure characteristics and mechanical properties of the existing angular contact ball bearing match way has been analyzed and compared,and then the applicability of them has been explained.For the existence of the high accuracy requirement and the low radial load capacity,a way of heterogeneous rolling bearing match way was put forward.Its characteristic is to use deep groove ball bearings or cylindrical roller bearing to bear radial load bearing,and angular contact ball bearing to bear axial load.Then,the formula was derived for calculating the life of a heterogeneous rolling bearing match way.At the same time the life calculation formula of"QBC"angular contact ball bearing was deduced.Comparison of the two above show that heterogeneous rolling bearing match way obviously improves the radial bearing capacity,obviously prolong service life,and the demand of bearing manufacturing and installation accuracy is low.The results have been applied to an import petrochemical plant methylamine pumps.After calculation,heterogeneous rolling bearing match way increases by 52.5%.