7 research outputs found

    A locally statistical active contour model for SAR image segmentation can be solved by denoising algorithms

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    In this paper, we propose a novel locally statistical variational active contour model based on I-divergence-TV denoising model, which hybrides geodesic active contour (GAC) model with active contours without edges (ACWE) model, and can be used to segment images corrupted by multiplicative gamma noise. By adding a diffusion term into the level set evolution (LSE) equation of the proposed model, we construct a reaction-diffusion (RD) equation, which can gradually regularize the level set function (LSF) to be piecewise constant in each segment domain and gain the stable solution. We further transform the proposed model into classic ROF model by adding a proximity term. Inspired by a fast denoising algorithm proposed by Jia-Zhao recently, we propose two fast fixed point algorithms to solve SAR image segmentation question. Experimental results for real SAR images show that the proposed image segmentation model can efficiently stop the contours at weak or blurred edges, and can automatically detect the exterior and interior boundaries of images with multiplicative gamma noise. The proposed FPRD1/FPRD2 models are about 1/2 (or less than) of the time required for the SBRD model based on the Split Bregman technique.Comment: 18 pages, 15 figures. arXiv admin note: substantial text overlap with arXiv:2312.11849, arXiv:2312.08376, arXiv:2312.0936

    Active contours driven by local and global intensity fitting energy with application to SAR image segmentation and its fast solvers

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    In this paper, we propose a novel variational active contour model based on Aubert-Aujol (AA) denoising model, which hybrides geodesic active contour (GAC) model with active contours without edges (ACWE) model and can be used to segment images corrupted by multiplicative gamma noise. We transform the proposed model into classic ROF model by adding a proximity term. Inspired by a fast denosing algorithm proposed by Jia-Zhao recently, we propose two fast fixed point algorithms to solve SAR image segmentation question. Experimental results for real SAR images show that the proposed image segmentation model can efficiently stop the contours at weak or blurred edges, and can automatically detect the exterior and interior boundaries of images with multiplicative gamma noise. The proposed fast fixed point algorithms are robustness to initialization contour, and can further reduce about 15% of the time needed for algorithm proposed by Goldstein-Osher.Comment: 20 pages,28 figures. arXiv admin note: substantial text overlap with arXiv:2312.08376, arXiv:2312.0936

    Examining associations of folic acid supplements administered to mothers during pre-conceptional and prenatal periods with autism spectrum disorders in their offspring: insights from a multi-center study in China

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    ObjectiveTo investigate the relationship between maternal folic acid (FA) supplementation during the pre-conceptional and prenatal periods and the subsequent risk of autism spectrum disorder (ASD) in offspring.MethodsA total of 6,049 toddlers aged 16–30 months were recruited from August 2016 to March 2017 for this cross-sectional study conducted in China. The parents of the enrolled toddlers provided information on maternal supplemental FA, socio-demographic information, and related covariates. Standard diagnostic procedures were implemented to identify toddlers with ASD.ResultsAmong the 6,049 children included in the study, consisting of 3,364 boys with an average age of 22.7 ± 4.1 months, a total of 71 children (1.2%) were diagnosed with ASD. Mothers who did not consume FA supplements during the prenatal period were found to have a significantly increased risk of having offspring with ASD, in comparison to those who were exposed to FA supplements (odds ratio [OR] = 2.47). However, we did not find a similar association during the pre-conceptional period. Compared to mothers who consistently used FA supplements from pre-conception to the prenatal period, those who never used FA supplements were statistically significantly associated with a higher risk of ASD in their offspring (OR = 2.88).ConclusionThis study indicated that providing continuous maternal FA supplementation during the pre-conceptional and prenatal periods may decrease the risk of ASD in offspring. The prenatal period is considered to be the most crucial time for intervention

    Investigation of Lung Cancer Patients Complicated with Chronic Obstructive Pulmonary Disease in Thoracic Surgical Department

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    Background and objective Lung cancer is an important complication of chronic obstructive pulmonary disease (COPD), and even significantly affects the prognosis of patients with COPD. COPD also affects the postoperative complications and recurrence in patients with lung cancer. This study aims to investigate lung cancer patients complicated with COPD in thoracic surgical department. Methods All medical records of lung cancer patients discharged from the Department of Thoracic Surgery of People’s Hospital, Peking University during January 2015 and December 2015 were reviewed, including gender, age, tobacco smoke history, harmful occupational exposure, clinic symptom, chest computed tomography (CT) scanning, postoperative pathology result report, discharged diagnosis and spirometry [All patients underwent pulmonary function test are received bronchial dilation test if the based predicted value of forced expiratory volume in one second (FEV1) <70%]. Results A full set of lung function test was measured in 703 lung cancer patients. Bronchial dilation test was finished in 67 patients. 62 (92.5%) patients were diagnosed as COPD. 677 cases with lung cancer were received surgery. Bronchial dilation test was measured in 42 cases. Of them 38 (92.7%) patients were diagnosed as COPD. It was found that the patients with lung cancer and COPD was more frequent in males, elders (≥65 yr), smokers, non-adenocarcinoma patients than those of patients without COPD (P<0.05). The males and the elders (≥65 yr) were more likely to suffer from COPD (OR: 2.374-2.807, 95%CI: 1.101-7.157)(P<0.05). Only 3 patients (4.3‰) were diagnosed as COPD and received standard treatment before admission. And only 5 patients (7.1‰) were diagnosed as COPD as discharged. Conclusion The routine pulmonary function as well as bronchial dilation test are helpful for screening the patients with COPD. At present, the diagnosis and treatment of lung cancer combined with COPD is a serious problem, which needs to be paid attention to by thoracic surgeons and to join hands with physicians in order to improve the diagnosis level of COPD
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