Linked color imaging vs Lugol chromoendoscopy for esophageal squamous cell cancer and precancerous lesion screening: A noninferiority study

BACKGROUND Lugol chromoendoscopy(LCE)has served as a standard screening technique in high-risk patients with esophageal cancer.Nevertheless,LCE is not suitable for general population screening given its side effects.Linked color imaging(LCI)is a novel image-enhanced endoscopic technique that can distinguish subtle differences in mucosal color.AIM To compare the diagnostic performance of LCI with LCE in detecting esophageal squamous cell cancer and precancerous lesions and to evaluate whether LCE can be replaced by LCI in detecting esophageal neoplastic lesions.METHODS In this prospective study,we enrolled 543 patients who underwent white light imaging(WLI),LCI and LCE successively.We compared the sensitivity and specificity of LCI and LCE in the detection of esophageal neoplastic lesions.Clinicopathological features and color analysis of lesions were assessed.RESULTS In total,43 patients(45 neoplastic lesions)were analyzed.Among them,36 patients(38 neoplastic lesions)were diagnosed with LCI,and 39 patients(41 neoplastic lesions)were diagnosed with LCE.The sensitivity of LCI was similar to that of LCE(83.7%vs 90.7%,P=0.520),whereas the specificity of LCI was greater than that of LCE(92.4%vs 87.0%,P=0.007).The LCI procedure time in the esophageal examination was significantly shorter than that of LCE[42(34,50)s vs 160(130,189)s,P<0.001].The color difference between the lesion and surrounding mucosa in LCI was significantly greater than that observed with WLI.However,the color difference in LCI was similar in different pathological types of esophageal squamous cell cancer.CONCLUSION LCI offers greater specificity than LCE in the detection of esophageal squamous cell cancer and precancerous lesions,and LCI represents a promising screening strategy for general populations.

Effects of Modular Threshing and Redrying on Color Difference and Polyphenols of Tobacco Leaves

[Objectives]This study was conducted to analyze changes of color difference and polyphenols and their relationship in the process of threshing and redrying.[Methods]The change trends of color difference parameters L,a,b,H^(0),C and polyphenol contents in tobacco leaves in the middle leaf module and the Pearson correlation between them were analyzed.[Results]During threshing and redrying,L and H^(0)of tobacco showed a decreasing trend,but H^(0)changed slightly;the values of a and C showed an inverted"S"change trend,and the differences between various processes were significant;and the value of b decreased first and then increased.The content of chlorogenic acid and scopoletin decreased first,then increased,and then decreased during threshing and redrying;rutin content showed a significant decreasing trend.The value of L was in an extremely significant positive correlation with rutin content;the value of a was in an extremely significant negative correlation with chlorogenic acid content;b value was also significantly correlated with rutin;and H^(0)was in significant correlation and extremely significant correlation with rutin and total polyphenols,respectively.[Conclusions]This study provides technical support for online detection of tobacco leaf components by the color difference method and for the homogenization of threshing and redrying.

New LED light source system with uniform illumination for line-scan CCD imaging systems

A system with uniform light reflection in the inner surface within a horizontal 2/3 cylindrical structure for line-scan CCD of the print testing was designed.The design was based on diffuse reflection uniformity of the integrating sphere and requirement of the strip uniform illumination region.This system was called dome light.White light LED array light sources were used for uniform illumination.The LEDs were filtrated to composite array light source based on coefficient of variation of a single LED.The standard white board and SG color checkers were used in the line-scan CCD imaging experiments under the dome light and ordinary illumination light source.The average color difference(ΔE)of SG color checkers in CIELAB space was 2.091 under the dome light and 2.286 under ordinary illumination light source respectively.Experimental results indicate that the dome light can satisfy illumination uniformity and color rendering consistency for line-scan CCD and provide a standard light source for uniform calibration of different cameras.

Effect of Bag Removing with Reflective Film Mulching Before Harvest on Fruit Coloration and Expression of Anthocyanin Related Genes in Peach

Appearance quality is the main element forming the fruit quality. Both bagging and reflective film application can improve appearance comprehensive quality. In order to determine the effects of bagging and reflective film on peach fruit coloration, this study explored the effects of applying reflective film before harvest on fruit appearance quality of peach(Prunus persica), and discussed the influencing mechanism on fruit coloration. Yellow outside and black inside double-layer bags were removed from fruit twelve days d before harvest. Peel color, pigment content, enzyme activity as well as the gene expression related to fruit coloration of a well-colored and late-ripening peach cultivar ‘Xiahui 8' with different treatments(non-bagging with non-reflective film mulching, debagging with non-reflective film mulching, debagging with reflective film mulching) were researched. The results showed that both debagging with non-reflective film mulching and debagging with reflective film mulching could significantly improve red and green color difference value(a*), a*/b*(b* is yellow and blue color difference value), chroma(C), anthocyanin(Ant) content and reduce hue angle(h), while debagging with reflective film mulching had higher Ant content than debagging with non-reflective film mulching(P < 0.05). The two treatments up-regulated the transcript level of anthocyanin biosynthetic related genes(UFGT, CHS) at the beginning of the experiment, however, the expression of DFR, LDOX and F3 H were enhanced along with the testing process. A downward trend on peel phenylalanine ammonia lyase(PAL) activity of non-bagging with non-reflective film mulching was observed during the experiment, however, the peel PAL activity of the other two treatments first increased and then decreased. What's more, peel PAL activity of debagging with reflective film mulching was higher than debagging with non-reflective film mulching. These results suggested that Ant synthesis in the peel was the result of cooperation among several genes, and debagging with reflective film mulching had better effect on promoting Ant accumulation than debagging with non-reflective film mulching.

Development of color density concept with color difference formulas in respect to human vision system

The aims of this study are to develop the color density concept and to propose the color density based color difference formulas.The color density is defined using the metric coefficients that are based on the discrimination ellipses and the locations of the colors in the color space.The ellipse sets are the MacAdam ellipses in the CIE 1931 xy-chromaticity diagram and the chromaticity-discrimination ellipses in the CIELAB space.The latter set was originally used to develop the CIEDE2000 color difference formula.The color difference can be calculated from the color density for the two colors under consideration.As a result,the color density represents the perceived color difference more accurately,and it could be used to characterize a color by a quantity attribute matching better to the perceived color difference from this color.Resulting from this,the color density concept provides simply a correction term for the estimation of the color differences.In the experiments,the line element formula and the CIEDE2000 color difference formula performed better than the color density based difference measures.The reason behind this is in the current modeling of the color density concept.The discrimination ellipses are typically described with three-dimensional data consisting of two axes,the major and the minor,and the inclination angle.The proposed color density is only a one-dimensional corrector for color differences;thus,it cannot capture all the details of the ellipse information.Still,the color density gives clearly more correct estimations to perceived color differences than Euclidean distances using directly the coordinates of the color space.

Rapid identification of two-dimensional materials via machine learning assisted optic microscopy

A combination of Fresnel law and machine learning method is proposed to identify the layer counts of 2D materials.Three indexes,which are optical contrast,red-green-blue,total color difference,are presented to illustrate and simulate the visibility of 2D materials on Si/SiO_(2) substrate,and the machine learning algorithms,which are k-mean clustering and k-nearest neighbors,are employed to obtain thickness database of 2D material and test the optical images of 2D materials via red-green-blue index.The results show that this method can provide fast,accurate and large-area property of 2D material.With the combination of artificial intelligence and nanoscience,this machine learning assisted method eases the workload and promotes fundamental research of 2D materials.