Joint polarization detection and degradation mechanisms for underwater image enhancement.

Light absorption and scattering exist in the underwater environment, which can lead to blurring, reduced brightness, and color distortion in underwater images. Polarized images have the advantages of eliminating underwater scattering interference, enhancing contrast, and detecting material information of the object in underwater detection. In this paper, from the perspective of polarization imaging, different concentrations (0.15 g/ml, 0.30 g/ml, and 0.50 g/ml), different wave bands (red, green, and blue), different materials (copper, wood, high-density PVC, aluminum, cloth, foam, cloth sheet, low-density PVC, rubber, and porcelain tile), and different depths (10 cm, 20 cm, 30 cm, and 40 cm) are set up in a chamber for the experimental environment. By combining the degradation mechanism of underwater images and the analysis of polarization detection results, it is proved that the degree of polarization images have greater advantages than degree of linear polarization images, degree of circular polarization images, S1, S2, and S3 images, and visible images underwater. Finally, a fusion algorithm of underwater visible images and polarization images based on compressed sensing is proposed to enhance underwater degraded images. To improve the quality of fused images, we introduce orthogonal matching pursuit (OMP) in the high-frequency part to improve image sparsity and consistency detection in the low-frequency part to improve the image mutation phenomenon. The fusion results show that the peak SNR values of the fusion result maps using OMP in this paper are improved by 32.19% and 22.14% on average over those using backpropagation and subspace pursuit methods. With different materials and concentrations, the underwater image enhancement algorithm proposed in this paper improves information entropy, average gradient, and standard deviation by 7.76%, 18.12%, and 40.8%, respectively, on average over previous algorithms. The image NIQE value shows that the image quality obtained by this paper's algorithm is improved by about 69.26% over the original S0 image.

Role of endoplasmic reticulum stress signaling pathway in high fat-induced cell apoptosis in vascular endothelial cells / 中国药理学通报

Aim To explore the role of endoplasmic reticulum stress(ERS)signaling pathway in high fat-induced cell apoptosis in human umbilical vein endo-thelial cells(HUVECs). Methods HUVECs were ex-posed to different concentrations of palmitic acid(0. 1, 0. 2,0. 4,0. 8 mmol·L - 1 )for 24 h and different time points of 0. 4 mmol·L - 1 palmitic acid(0,12, 24,48 h). Cell viability was measured by cell count-ing kit(CCK-8),and the protein expressions of ERS signaling pathway protein such as GRP78,CHOP, PERK,IRE1,ATF6 were determined by Western blot. The level of intracellular apoptosis was detected by immunofluorescence. Results HUVECs exposed to palmitic acid at 0. 4 mmol·L - 1 for 24 h showed a de-crease in their viability and an increase in the expres-sion of ERS signaling pathway proteins (GRP78, CHOP,PERK,IRE1,ATF6)(P < 0. 05);cell ap-optotic levels significantly increased(P < 0. 05). The intracellular apoptosis levels in the vascular endothelial cells of ERS signaling pathway inhibitor 4-phenylbutyr-ic acid (4-PBA,10 mmol · L - 1 )were significantly lower than those of the PA group(P < 0. 05). Conclu-sion Activated ERS signaling pathway might play an important role in the treatment of high fat-induced cell apoptosis in vascular endothelial cells.

Role of NADPH oxidase in high fat-induced oxidative stress injury in human umbilical vein endothelial cells / 中国药理学通报

Aim To explore the role of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase in high fat-induced oxidative stress injury in human umbilical vein endothelial cells (HUVECs).Methods HUVECs were exposed to different concentrations of palmitic acid(0.1,0.2,0.4,0.8 mmol · L-1) for 24 h and different time points of 0.4 mmol · L-1 palmitic acid(0,12,24,48 h).Cell viability was measured by Cell Counting Kit 8,and the protein expression of NADPH oxidase subunits such as p22phox,p47phox,p67phox and gp91phox were determined by Western blot.The expression of reactive oxygen species (ROS) in HUVECs was detected by immunofluorescence.Results Cell proliferation rate of HUVECs stimulated by 0.4 mmol · L-1 palmitic acid for 24 h and 48 h was significantly reduced.In the next experiment,model group was accordingly set as HUVECs stimulated by 0.4 mmol · L-1 palmitic acid for 24 h.The expression of NADPH oxidase subunits such as p22phox,p47phox,p67phox and gp91phox significantly increased at 24 h and 48 h after 0.4 mmol· L-1 palmitic acid stimulation (P ＜ 0.05),and the difference.between the 24 h group and the 48 h group was not significant (P ＞ 0.05).The expression of ROS in HUVECs significantly increased at 24 h and 48 h after O.4 mmol · L-1 palmitic acid stimulation (P ＜ 0.05),and the difference between 24 h group and 48 h group was not significant (P ＜ 0.05).Compared with the model group (0.4 mmol · L-1 palmitic acid stimulation for 24 h),the NADPH oxidase inhibitor diphenyliodonium (DPI,10 μmol · L-1) pretreatment could significantly decrease the expression of ROS in vascular endothelial cells (P ＜ 0.05).Conclusion Activated NADPH oxidase might play an important role in treatment of high fat-induced oxidative stress injury in vascular endothelial cells.

Application of IMA and H-FABP in Forensic Diagnosis of Sudden Cardiac Death / 法医学杂志

Acute myocardial ischemia is the most common cause of sudden cardiac death.The diagnosis of early myocardial ischemia is a hot point in forensic medicine,which is also an early and important part for a prevention against myocardial infarction.This paper conducts a comprehensive discussion of the structure,function,clinical value and forensic medicine application prospect of ischemia modified albumin (IMA) and heart-type fatty acid binding protein (H-FABP),aiming to determine whether the two proteins can be used as biochemical detection indicators of early myocardial ischemia for the diagnosis of sudden cardiac death in forensic medicine.

Application of Ischemia Modified Albumin for Acute Ischemic Heart Disease in Forensic Science / 法医学杂志

Objective To explore the application value and forensic significance of ischemia modified albumin (IMA) in pericardial fluid to diagnose sudden cardiac death.Methods IMA level in pericardial fluid was detected in acute ischemic heart disease group (n=36),acute myocardial infarction group (n=6),cardiomyopathy group (n=4) and control group (n=15) by albumin cobalt binding method.The levels of IMA were compared among these groups.The best cut-off IMA value was estimated and the sensitivity and specificity of acute myocardial ischemia group was distinguished from control group by receiver operating characteristics (ROC) curve.Results The IMA level in acute ischemic heart disease group was significantly higher than that of control group (P＜0.05).Compared with acute myocardial infarction group and cardiomyopathy group,the IMA level in acute ischemic heart disease group had no significant difference (P＜0.05).The cut-off value for the identification of acute myocardial ischemia which obtained by ROC analysis was 40.65U/mL.And the sensitivity and specificity for distinguishing acute ischemia cardiac disease was 60.0％ and 80.5％,respectively.Conclusion The IMA value in pericardial fluid can be a reference marker for the diagnosis of acute myocardial ischemia,which also can provide objective basis for the forensic identification of sudden cardiac death.