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Background: Diagnostic type II endometrial carcinoma (EC) is considered more aggressive and has a poorer prognosis than type I EC; differentiation between them is helpful for preoperative clinical decision-making. However, the diagnostic value of the apparent diffusion coefficient (ADC) in differentiating them remains unclear. Purpose: To investigate the value of ADC in differentiating type II EC from type I EC. Material and Methods: Ninety-four patients with EC who underwent diffusion-weighted imaging (DWI) were retrospectively included and divided into type I and type II subgroups, based on the postoperative pathologic results. We analyzed the clinical characteristics, conventional magnetic resonance imaging manifestations, and ADC mean values (ADCmean), ADC minimum values (ADCmin), and ADC max values (ADCmax). Receiver operating characteristic (ROC) curve analysis was further used to assess the predictive performance. Results: The ADCmean, ADCmin, and tumor size differed significantly between the two subtypes. The area under the ROC curve (AUC) for ADCmean and ADCmin was 0.787 (95% confidence interval [CI] = 0.692–0.88) and 0.835 (95% CI = 0.751–0.919) for predicting type II EC, respectively. The optimal cut-off value of ADCmean for prediction was 0.757 × 10–3 mm2/s with a sensitivity of 91%, a specificity of 58%, and an accuracy of 74%, while for ADCmin was 0.637 × 10–3 mm2/s with a sensitivity of 82%, a specificity of 73%, and an accuracy of 75%. Conclusion: EC with lower ADCmean and ADCmin values derived from DWI, and a larger size, are indicative of type II EC. [ABSTRACT FROM AUTHOR]

The influences of withdrawal rate and mold heater zone temperature during high rate solidification (HRS) on the microstructures were investigated. As the results, the primary dendritic spacing, the size of γ′ phase particles and carbides are decreased with the increase of the withdrawal rate or mold heater zone temperature. As the withdrawing goes on, the primary dendritic spacing and the size of γ′ phase particles are increased, and the heat emission efficiency of HRS process is decreased. The results show that fine dendrite and γ′ phase can be achieved with the withdrawal of 8 mm/min and mold heater zone temperature of 1520 ℃/1530 ℃, which is benefit to improve the properties of DZ466 alloy.

A 3-SPS/S parallel rehabilitation mechanism is proposed for the present situation of ankle rehabilitation institutions and the constitution of mechanism is introduced. The degree of freedom is calculated and the position inverse solution equation is established. Combined with numerical examples,the solution of the inverse equation is solved by MATLAB and the simulation results are verified by ADAMS. The simulation results show that the robot can meet the needs of ankle joint rehabilitation by changing the branching movement input.

A six degree of freedom 4-PRP+3-UPS&PU redundant hybrid machine tool is proposed,and the statics and static stiffness of the machine tool is studied. Firstly,based on the force Jacobi matrix,the static equilibrium equation is presented,and the mapping matrix between the external load and the driving force and the binding force of the branch is solved. Secondly,the binding screw provided by each drive branch and constraint branch is analyzed,the elastic deformation of each rod under the action of the constraint screw is calculated. Finally,the stiffness model of the mechanism is established,and the elastic deformation of each branch is superposed,and then the overall flexibility and stiffness matrix of the mechanism are obtained. Combined with numerical examples,the MATLAB software is used to calculate the curves of the elastic deformation of each driving and moving platform with the length of the drive rod.

We describe a convenient and useful procedure for the synthesis of various 2,5-dimethyl-N-substituted pyrrole derivatives by the addition of 2,5-hexadione with aromatic amines, heteroaromatic amines and aliphatic amines catalyzed by MgI2 etherate (MgI2·(OEt2)n) in good to excellent yields.