Currently,60 million women of reproductive age(18-44 years old) worldwide,and approximately 3 million American women have diabetes mellitus,and it has been estimated that this number will double by 2030.Pregestational...Currently,60 million women of reproductive age(18-44 years old) worldwide,and approximately 3 million American women have diabetes mellitus,and it has been estimated that this number will double by 2030.Pregestational diabetes mellitus(PGD) is a significant public health problem that increases the risk for structural birth defects affecting both maternal and neonatal pregnancy outcome.The most common types of human structural birth defects associated with PGD are congenital heart defects and central nervous system defects.However,diabetes can induce birth defects in any other fetal organ.In general,the rate of birth defects increases linearly with the degree of maternal hyperglycemia,which is the major factor that mediates teratogenicity of PGD.Stringent prenatal care and glycemic control are effective means to reduce birth defects in PGD pregnancies,but cannot reduce the incidence of birth defects to the rate of that is seen in the nondiabetic population.Studies in animal models have revealed that PGD induces oxidative stress,which activates cellular stress signalling leading to dysregulation of gene expression and excess apoptosis in the target organs,including the neural tube and embryonic heart.Activation of the apoptosis signalregulating kinase 1(ASK1)-forkhead transcription factor 3a(Fox O3a)-caspase 8 pathway causes apoptosis in the developing neural tube leading to neural tube defects(NTDs).ASK1 activates the c-Jun-N-Terminal kinase 1/2(JNK1/2),which leads to activation of the unfolded protein response and endoplasmic reticulum(ER) stress.Deletion of the ASK1 gene,the JNK1 gene,or the JNK2 gene,or inhibition of ER stress by 4-Phenylbutyric acid abrogates diabetes-induced apoptosis and reduces the formation of NTDs.Antioxidants,such as thioredoxin,which inhibits the ASK1-Fox O3a-caspase 8 pathway or ER stress inhibitors,may prevent PGD-induced birth defects.展开更多
In this study,an image binarization optimization algorithm,based on local threshold algorithms,is proposed because global and traditional local threshold segmentation algorithms cannot effectively address the problems...In this study,an image binarization optimization algorithm,based on local threshold algorithms,is proposed because global and traditional local threshold segmentation algorithms cannot effectively address the problems of nonuniform backgrounds of wood defect images.The proposed algorithm calculates the threshold by the mean,standard deviation and the extreme value of the window.The results indicate that this modified algorithm enhances the image segmentation for wood defect images on a complex background,which is much superior to the global threshold algorithm and the Bernsen algorithm,and slightly better than the Niblack algorithm and Sauvola algorithm.Compared with similar models,the algorithm proposed in this paper has higher segmentation accuracy,as high as 92.6%for wood defect images with a complex background.展开更多
Detection of wood plate surface defects using image processing is a complicated problem in the forest industry as the image of the wood surface contains different kinds of defects. In order to obtain complete defect i...Detection of wood plate surface defects using image processing is a complicated problem in the forest industry as the image of the wood surface contains different kinds of defects. In order to obtain complete defect images, we used convex optimization(CO) with different weights as a pretreatment method for smoothing and the Otsu segmentation method to obtain the target defect area images. Structural similarity(SSIM) results between original image and defect image were calculated to evaluate the performance of segmentation with different convex optimization weights. The geometric and intensity features of defects were extracted before constructing a classification and regression tree(CART) classifier. The average accuracy of the classifier is 94.1% with four types of defects on Xylosma congestum wood plate surface: pinhole, crack,live knot and dead knot. Experimental results showed that CO can save the edge of target defects maximally, SSIM can select the appropriate weight for CO, and the CART classifier appears to have the advantages of good adaptability and high classification accuracy.展开更多
基金Supported by NIH R01DK083243,R01DK101972 and R56 DK095380(to Yang P),R01DK103024(to Yang P and Reece EA)Basic Science Award(1-13-BS-220)American Diabetes Association(to Yang P)
文摘Currently,60 million women of reproductive age(18-44 years old) worldwide,and approximately 3 million American women have diabetes mellitus,and it has been estimated that this number will double by 2030.Pregestational diabetes mellitus(PGD) is a significant public health problem that increases the risk for structural birth defects affecting both maternal and neonatal pregnancy outcome.The most common types of human structural birth defects associated with PGD are congenital heart defects and central nervous system defects.However,diabetes can induce birth defects in any other fetal organ.In general,the rate of birth defects increases linearly with the degree of maternal hyperglycemia,which is the major factor that mediates teratogenicity of PGD.Stringent prenatal care and glycemic control are effective means to reduce birth defects in PGD pregnancies,but cannot reduce the incidence of birth defects to the rate of that is seen in the nondiabetic population.Studies in animal models have revealed that PGD induces oxidative stress,which activates cellular stress signalling leading to dysregulation of gene expression and excess apoptosis in the target organs,including the neural tube and embryonic heart.Activation of the apoptosis signalregulating kinase 1(ASK1)-forkhead transcription factor 3a(Fox O3a)-caspase 8 pathway causes apoptosis in the developing neural tube leading to neural tube defects(NTDs).ASK1 activates the c-Jun-N-Terminal kinase 1/2(JNK1/2),which leads to activation of the unfolded protein response and endoplasmic reticulum(ER) stress.Deletion of the ASK1 gene,the JNK1 gene,or the JNK2 gene,or inhibition of ER stress by 4-Phenylbutyric acid abrogates diabetes-induced apoptosis and reduces the formation of NTDs.Antioxidants,such as thioredoxin,which inhibits the ASK1-Fox O3a-caspase 8 pathway or ER stress inhibitors,may prevent PGD-induced birth defects.
基金supported by National Forestry Public Welfare Industry Scientific Research Special Subsidy Project(201304502)
文摘In this study,an image binarization optimization algorithm,based on local threshold algorithms,is proposed because global and traditional local threshold segmentation algorithms cannot effectively address the problems of nonuniform backgrounds of wood defect images.The proposed algorithm calculates the threshold by the mean,standard deviation and the extreme value of the window.The results indicate that this modified algorithm enhances the image segmentation for wood defect images on a complex background,which is much superior to the global threshold algorithm and the Bernsen algorithm,and slightly better than the Niblack algorithm and Sauvola algorithm.Compared with similar models,the algorithm proposed in this paper has higher segmentation accuracy,as high as 92.6%for wood defect images with a complex background.
基金supported by the Fund of Forestry 948project(2015-4-52)the Fundamental Research Funds for the Central Universities(2572017DB05)the Natural Science Foundation of Heilongjiang Province(C2017005)
文摘Detection of wood plate surface defects using image processing is a complicated problem in the forest industry as the image of the wood surface contains different kinds of defects. In order to obtain complete defect images, we used convex optimization(CO) with different weights as a pretreatment method for smoothing and the Otsu segmentation method to obtain the target defect area images. Structural similarity(SSIM) results between original image and defect image were calculated to evaluate the performance of segmentation with different convex optimization weights. The geometric and intensity features of defects were extracted before constructing a classification and regression tree(CART) classifier. The average accuracy of the classifier is 94.1% with four types of defects on Xylosma congestum wood plate surface: pinhole, crack,live knot and dead knot. Experimental results showed that CO can save the edge of target defects maximally, SSIM can select the appropriate weight for CO, and the CART classifier appears to have the advantages of good adaptability and high classification accuracy.
