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Newton’s rings are often encountered in interferometry, and in analyzing them, we can estimate the physical parameters, such as curvature radius and the rings’ center. The fractional Fourier transform (FRFT) is capable of estimating these physical parameters from the rings despite noise and obstacles, but there is still a small deviation between the estimated coordinates of the rings' center and the actual values. The least-squares fitting method is popularly used for its accuracy but it is easily affected by the initial values. Nevertheless, with the estimated results from the FRFT, it is easy to meet the requirements of initial values. In this paper, the proposed method combines the advantages of the fractional Fourier transform (FRFT) with the least-squares fitting method in analyzing Newton’s rings fringe patterns. Its performance is assessed by analyzing simulated and actual Newton’s rings images. The experimental results show that the proposed method is capable of estimating the parameters in the presence of noise and obstacles. Under the same conditions, the estimation results are better than those obtained with the original FRFT-based method, especially for the rings’ center. Some applications are shown to illustrate that the improved FRFT-based method is an important technique for interferometric measurements.

By analyzing Newton's rings, often encountered in interferometry, using fractional Fourier transform (FRFT), we can estimate the physical parameters, such as the curvature radius of the spherical surface and the rings' center. However, parameter estimation from large images using FRFT consumes considerable time. We introduce an improved method that resamples the image before applying FRFT. Because Newton's rings are sparse in the FRFT domain, this method reduces the computational time without decreasing the accuracy. Experimental results show that compared to traditional FRFT-based algorithms, this method can estimate parameters in about 1.3 s when processing 1920×1080 pixel images.

Background A few studies have been conducted on the relationship between cerebellar volume and emotional memory or clinical severity in major depressive disorder (MDD). In this study, we aimed to compare the volume and density of the cerebellar gray matter (GM) in patients with MDD and in healthy controls (HCs) and explore the association between these cerebellar parameters and measurements of emotional memory and clinical severity. Method Voxel-based morphometry (VBM) and Individual Brain Atlases using Statistical Parametric Mapping (IBASPM) were used to assess GM density and volume in the cerebellum, respectively, in patients with MDD and the HCs. Indicators of emotional memory performance were measured, including the hit rate (HR), rate of false alarm (FA), precision (Pr = HR − FA) and emotional memory enhancement [∆Pr = Pr(emotion) − Pr(neutral)] values. Beck Depression Inventory (BDI) scores were used to measure the severity of depression. Results In the patients with MDD, the GM density was decreased in three cerebellar cortical regions and increased in three cerebellar cortical regions (p

Objective: To investigate the effects of neoadjuvant chemotherapy on the expression of drug resistance genes, multidrug resistance-1 (MDR1) and multidrug resistance-associated protein (MRP), in patients with primary breast cancer. Methods: MDR1 and MRP expression were detected by semi-quantitative RT-PCR in 20 patients with primary breast cancer, before and after chemotherapy. Results: Before chemotherapy, MDR1 and MRP expression can be detected in 15 cases (75%) and 18 cases (90%) respectively. After chemotherapy, expression of MDR1 is not significantly different from that before chemotherapy, but expression of MRP is significantly different from that before chemotherapy. Conclusion: Expression of drug resistance gene MRP, but not MDR1, is enhanced in patients with primary breast cancer submitted to neoadjuvant chemotherapy.

AIM: To investigate the expression of pathological factors of VEGF-C and its receptor FLT-4 in primary gastric cancer and adjacent normal tissues. METHODS: The expression of VEGF-C and FLT-4 was studied in 80 primary gastric cancers and adjacent normal tissues from the same patients by semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) and immumohistochemistry. RESULTS: Both primary gastric cancer and adjacent normal tissue could express VEGF-C and FLT-4, and FLT-4 expression was also detected in endothelial cells of stromal blood vessels and lymphatic vessels. There was a significant difference in expression of VEGF-C between primary tumor and adjacent normal tissue samples (P = 0.01), and a statistical correlation between VEGF-C and FLT-4 expression in tumors (P = 0.00886). With regard to VEGF-C expression, there was a significant difference between moderate-poor differential type and high differential type (P = 0.032), and a significant difference between positive and negative lymph node metastases (P = 0.024). However, there was no significant difference between positive and negative serosal invasions (P = 0.219). CONCLUSION: VEGF-C and its receptor FLT-4 play a role in the development of gastric cancer, and the tumors with expression of VEGF-C and FLT-4 are more likely to have lymph node metastasis.

AIM: To evaluate of scoring system in predicting choledocholithiasis in selective intraoperative cholangiography (IOC) during laparoscopic cholecystectomy (LC). METHODS: The scoring system of predicting choledocholithiasis was developed during the retrospective study in 264 cases, and was tested in 184 to evaluate its predictive value in choledocholithiasis. RESULTS: The scoring system was developed in a retrospective study of 264 cases, the statistical analyses showed the predictive factors included sex, transaminase levels, alkaline phosphatase level, bilirubin level, and common bile duct diameter on ultrasonography. The scoring system was used in 184 cases prospectively, of which, 3 of 162 (1.9%) cases scoring < 3 had choledocholithiasis, 17 of 22 (77.3%) cases scores≥3 had choledocholithiasis. A case of scores≥3 or more prospectively should be considered highly intraoperative cholangiography during laparoscopic cholecystectomy. CONCLUSION: The scoring system can predict choledocholithiasis and is helpful in selection patietns for intraoperative cholangiography.