Case Report: Semi-Ex Vivo Hepatectomy Combined with Autologous Liver Transplantation for Alveolar Echinococcosis in Children.

Hepatic alveolar echinococcosis (AE) is a zoonotic disease caused by the metacestode of Echinococcus multilocularis. Although surgical resection is the optimal treatment for hepatic AE, some patients with hepatic AE located in special introhepatic sites cannot be radically cured by conventional surgery. Here, we report that a 10-year-old female patient was admitted to the hospital with occupying liver lesions for 6 months. Computed tomography examination showed irregular mixed-density masses in the right lobe and caudate lobe of the liver, with partial invasion of the right hepatic artery, right hepatic vein, and right branch of the portal vein. The patient was preoperatively diagnosed with hepatic AE, which cannot be cured by conventional liver lobectomy. The patient underwent semi-ex vivo liver resection with autologous liver transplantation (second hepatic portal reconstruction, posterior hepatic inferior vena cava repair, and hepatic artery repair) and biliary-intestinal anastomosis. After hospital discharge, she has kept living a healthy life without disease recurrence for 13 months until the end of the last follow-up. This case shows that semi-ex vivo hepatectomy with autologous liver transplantation might be a feasible and safe choice for certain patients with AE located in special introhepatic sites, which has provided novel experiences for the surgical treatment of hepatic AE.

High-precision processing method for an aluminum mirror assisted with a femtosecond laser.

At present, aluminum-based optical payloads are widely used in the aviation and aerospace field, and the demand for aluminum mirrors has become increasingly urgent in the visible light region. The main processing of an aluminum alloy mirror involves single-point diamond turning followed by a combined polishing process. Among these processes, magnetorheological finishing (MRF) is an important method for improving a surface figure. During the MRF process, excessive impurity contaminants are introduced into the surface of the aluminum mirror, thereby reducing surface reflectivity. In this paper, theoretical analysis and time-of-flight secondary ion mass spectrometry depth profiling were used to obtain the cause of pollution, and the process scheme of femtosecond laser cleaning was proposed. After verifying the feasibility, a new, to the best of our knowledge, process route was implemented on a Φ50mm aluminum mirror. Finally, the surface figure of RMS 0.022λ and the surface roughness of Ra 3.24 nm were obtained. In addition, reflectance in the visible light and near-infrared bands has increased by about 50%.

Study on the surface crystallization mechanism and inhibition method in the CMP process of aluminum alloy mirrors.

Owing to its material properties, aluminum-based optical loads are widely used in the aerospace field. At present, the main processing of an aluminum alloy mirror is single-point diamond turning followed by the combined polishing process. The surface will generate some white crystals during the chemical mechanical polishing process (CMP). These crystals can affect the improvement of surface quality and seriously reduce the processing efficiency of the whole process. In view of the above problems, four main factors of crystallization are obtained by interface theoretical analysis, Visual MINTEQ simulation of chemical morphological distribution, and experimental analysis. They are temperature, PH value of polishing fluid, solid-liquid contact angle, and impurity content of aluminum alloy. The crystallization phenomenon in the polishing process is successfully suppressed by improving the polishing process and selecting new materials. The experimental results showed that the surface roughness decreased from 7.21 to 2.98 nm without crystallization using the new method.

Fringe discretization and manufacturing analysis of a computer-generated hologram in a null test of the freeform surface.

A computer-generated hologram (CGH) is the core component for an aspheric surface test. According to fabrication demands, it is necessary to convert the designed CGH phase compensation function into the processed pattern, that is, the fringe discretization process. In this paper, we propose a new discretization method for a CGH in a test of the freeform surface, and realized the encoding of processed fringes by MATLAB software. Furthermore, we designed the experiment to verify the accuracy of the new discretization method and compared the calculation efficiency between the new algorithm and the reported algorithm. Finally, based on the testing requirement of a freeform mirror in a camera optical system, we completed the design, encoding, and fabrication of the CGH sample, and analyzed the influence of various errors on wavefront accuracy of the CGH.