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2021 ◽  
Vol 9 (1) ◽  
pp. 18
Author(s):  
Merel Arink ◽  
Haris Ahmad Khan ◽  
Gerrit Polder

Tomato is an important food product for which the development of non-destructive quality assessment methods is of great interest. Using visible and near-infrared (NIR) spectroscopy, the sugar content, acidity and even taste can be estimated through the use of chemometric methods (e.g., partial least squares regression). In the case of reflection spectra, which are the common modality for imaging spectroscopy, the question arises regarding how much of the interior of the tomato contributes to the measured spectra. An experiment was performed with tomatoes of four different types: beef tomato, classic round tomato, cocktail tomato, and snack tomato. The tomatoes were sliced at different thicknesses and imaged on a 98% reflective white background and a 4% reflective black background. Spectral images were acquired with VNIR (400–1000 nm) and NIR (900–1700 nm) imaging spectrographs. The difference between the spectra with a white and black background was used to determine the relationship between the wavelength and the light penetration depth. The results show that at wavelengths between 600 and 1100 nm, light penetrates the tomatoes up to a distance of 20 mm. The relation more or less follows the law of Lambert–Beer. This relation was the same for all four types of tomatoes. These results help the interpretation of chemometric models based on reflection (imaging) spectroscopy.


2021 ◽  
Vol 29 (6) ◽  
pp. 38-41
Author(s):  
Sandy M.S. McLachlan ◽  
Elaine C. Humphrey

Abstract:We describe an experimental approach for achieving an optimal black background for scanning electron photomicrographs of small samples with elaborate and intricate structures. Specimens of the highly ornate, 66-million-year-old chorate dinoflagellate cyst species Cannosphaeropsis franciscana were selected as the subject of this study. Photomicrographs collected following standard aluminum stub surface placement were compared to those taken of specimens mounted using a novel pin-and-pedestal method. This simplistic mounting technique minimizes the need for post-production image editing and extraneous background removal.


2021 ◽  
Author(s):  
M Saegusa ◽  
H Kurokawa ◽  
N Takahashi ◽  
T Takamizawa ◽  
R Ishii ◽  
...  

Clinical Relevance Although excellent color-matching ability was confirmed for the structural colored resin composite Omnichroma, care should be taken to ensure that the appropriate chromatic color conditions for restoration are achieved in the oral environment. SUMMARY Purpose: The present study evaluated the color-matching ability of a structural colored resin composite to compare it with resin composites employing pigments. Methods and Materials: A structural colored resin composite (Omnichroma [OMC]), a supranano-filled resin composite (Estelite Σ Quick [ELQ]), and a nano-filled resin composite (Filtek Supreme Ultra [FSU]) were used. Each resin composite was packed into a Teflon mold and pressed down with a clear strip under a glass slide. The specimens were light irradiated through the slide with a light-emitting diode curing unit. The thickness of the specimens (n=6) was measured with a digital caliper before being transferred to distilled water and stored at 37°C for 24 hours. The measurements of the optical characteristics of the specimens on a black-and-white background were performed using a spectrophotometer. D65 (CIE D65) was used as a light source for the spectrophotometer. Measurements were repeated three times for each specimen under each color-measurement condition, and average values for three same-shade specimens were calculated. One-way analysis of variance and Tukey post hoc tests were used (α=0.05). To determine its ability to match the color of artificial teeth, each shade of resin composite was placed in a cavity before performing color measurements. Using a spectrophotometer (CMS-35F S/C) with a flexible sensor, L*, a*, and b* values were obtained. Results: The spectral reflectance curve of OMC showed that it reflected light wavelengths from 430-700 nm regardless of the background color and thickness of the specimens. The percentage of reflectance of ELQ decreased near wavelengths of 550-580 nm. Regarding the influence of background color on CIE L*, a*, b* values, the L* level showed significantly higher values for all tested materials with white backgrounds, and OMC was most affected by the difference in background color. However, a* values of ELQ and FSU were significantly higher with a black background than with a white background, and OMC showed a significantly higher value with a white background than with a black background. The b* values were higher with a white background than with a black background and were significantly higher for all three products, and these tendencies were much greater for ELQ and FSU. Conclusions: The ability of OMC to match the color of artificial teeth showed acceptable color compatibility, regardless of the shade of the artificial teeth and the depth of the cavity. However, ELQ and FSU showed reduced color compatibility, especially for a cavity depth of 3.0 mm. Excellent color matching ability was confirmed for the structural colored resin composite OMC, resulting in reduced color differences and therefore improving the esthetic appearance of the restoration, simplifying shade matching, and compensating for any color mismatch.


2021 ◽  
Vol 18 (2) ◽  
pp. 309-316
Author(s):  
S. I. Rychkova ◽  
V. G. Likhvantseva

The work is devoted to one of the actual problems of modern strabismology — the study of the ability to stereo perception in children with non-paralytic strabismus.Purpose: to study the capability to stereovision with alternating presentation of stereostimuli in children with functional scotoma in non-paralytic strabismus.Patients and methods. 113 children with functional scotoma (FS) in non-paralytic strabismus were observed. We used stereostimuli with different characteristics in the following regimes of presentation: 1) the regime of simple monocular alternating (alternate presentation of an image for the right eye and the left eye); 2) the regime having an “empty” interval (black background) between monocular phases; 3) the regime having a binocular phase (a binocular image containing details corresponding to the stimuli for the right eye and the left eye) between monocular phases.Results. It was found that in 23 (20,3 %) children, the ability to stereo perception was completely absent. All these children had stable total FS (monocular vision). In the remaining 90 children (with unstable or regional FS), the ability to stereo perception was shown with some stimuli in some modes of their alternating presentation. For stimuli with a central arrangement of linear parts, the stereo effect was possible when they were presented in an alternating mode with an “empty” interval lasting from 20 to 70 ms in combination with the duration of monocular phases from 30 to 90 ms. For stimuli with a peripheral arrangement of linear elements, 22.1 % of children were able to stereo perception not only in the “empty” interval mode, but also in the simple alternation mode. At the same time, the greatest number of children capable of stereo perception was detected when using the mode with an “empty” interval of 30–60 ms and a duration of monocular phases of 40–60 ms. With random-dot stimuli, none of the children in this group were capable of stereo perception.Conclusion. Our results suggest that even in patients with FS in non-paralytic strabismus, stereo perception is possible under the conditions of alternating presentation of stimuli with certain characteristics. In this case, the most likely appearance of a stereo effect with stimuli containing peripheral linear elements that create a stereo effect when presented in an alternating mode with an empty interval between monocular phases. 


Zootaxa ◽  
2021 ◽  
Vol 4969 (2) ◽  
pp. 318-330
Author(s):  
WORAWITOO MEESOOK ◽  
MONTRI SUMONTHA ◽  
NATTASUDA DONBUNDIT ◽  
OLIVIER S. G. PAUWELS

We describe Gekko pradapdao sp. nov. from Tham Khao Chan (Khao Chan Cave), Tha Luang District, Lopburi Province, in central Thailand. The new species, a member of the subgenus Gekko, differs from all currently recognized Gekko species by the following combination of morphological characters and pattern: maximal known snout-vent length of 127.1 mm, lack of contact between nostrils and rostral, 24–28 interorbital scales between supraciliaries, 89–91 scale rows around midbody, 16–18 dorsal tubercle rows at midbody, 30–34 ventral scale rows at midbody, 11–13 precloacal pores in males, a single postcloacal tubercle on each side of the base of the tail, 13–16 subdigital lamellae on 1st toe and 17–19 on 4th toe, no Y-shaped mark on head, non-banded dorsal pattern on a dark chocolate brown to black background, and a dark brown iris. Urgent actions should be taken to evaluate the conservation status of the new species. 


Author(s):  
Jessica L King ◽  
Connor Simper ◽  
Jacob Razzouk ◽  
Julie W Merten

Abstract Introduction Advertisement warnings are often overlooked, which reduces the opportunity for risk communication. Methods We used Prolific to survey 1,131 young adults (18-35) who currently used e-cigarettes or tobacco products. We randomized participants to one of four warning conditions: black text on white background (BW), white on black (WB), black on yellow (BY), and yellow on black (YB). We examined associations between condition and attention, recall, ad appeal, perceived message effectiveness (PME), and intentions to use e-cigarettes using chi-square and ANOVA where appropriate. We conducted logistic regressions by condition for attention and recall controlling for demographics and tobacco use. Results The warning was selected as the most attention-capturing area of the advertisement more often by those exposed to yellow warnings than white (59.9% versus 46.8%), even after controlling for demographics and tobacco use (p<.05). Recall was greater among those exposed to yellow warnings than white (44.2% vs. 37.3%), which held in controlled models. There were no significant differences between yellow and white warnings for ad appeals, PME, or intentions to use. In subanalyses, WB warnings generated higher PME (10.1 vs. 9.5) and lower intentions to use e-cigarettes (3.0 vs. 3.3) than BW (each p<.05). Conclusions Yellow warning color increases attention and recall of the warning, but this increase in attention did not translate to differences in downstream effects. Among currently mandated warning variations, the white text on black background warning appears more effective than the black on white. Future research should examine whether differences translate to behavior change. Implications We tested color variations of the FDA-mandated nicotine text warning on e-cigarette advertisements. Yellow variations (yellow text on black background and black on yellow) better captured attention and increased warning recall compared to the mandated black and white warnings. Among the FDA-mandated black on white and white on black warnings, the white on black variation appears more effective, generating higher perceived message effectiveness and lower intentions to use e-cigarettes. Given the difficulty in implementing pictorial warnings in the US, color might represent an alternative to improve warning effectiveness. Findings may also be applicable to those designing tobacco-related health communications.


Author(s):  
Alexandra I. Strukova ◽  
◽  
◽  

This article considers the phenomenon of the authors’ signatures of Vladimir Grinberg (1896—1942) and Alexander Vedernikov (1898—1975), two representatives of the Leningrad Landscape School community in the 1930s—1940s. During this period, they entered a single circle of friendly and professional communication and experienced mutual influences. The artists’ work is considered more broadly and goes beyond their participation in the community. The goal of the article is to single out the most significant periods of their activity, trace changes in the authors’ handwriting from decade to decade, pay attention to the period of apprenticeship and formation of the artists, and focus on controversial issues in the attribution of their paintings and drawings. A study of all the works by Grinberg and Vedernikov currently identified in museum and private collections, makes it possible to trace the changes in the authors’ styles and discover the artistic landmarks of the masters. Grinberg’s manner repeatedly transformed. The neoclassical stylistics of his works of the late 1910s and citation of paintings by the old masters gave way to modest still lifes in the 1920s. After landscapes and scenes of everyday life on a black background in the early 1930s, there was a lightening of the colour scheme during his work on the New Leningrad series in the middle of the decade. In the early 1940s, Grinberg began to paint very broadly, generalising and simplifying the images. This scandalising manner has parallels with the style of the 1960s. Vedernikov was influenced by the art of French post-impressionists. Also, he took interest in the art of Russian folk crafts in the post-war period, more particularly, in Gorodets painting. The article pays much attention to Grinberg’s and Vedernikov’s lithographs. A significant part of their works has been catalogued and published, which facilitates dating and attribution, but much remains unknown (for example, an episode in Vedernikov’s work associated with the unification of the Masters of Analytical Art). In the article, the author describes the marking of works in detail, the placement and outline of the signatures, and traces the changes in them, which will help determine the range of works and authorship more accurately.


Author(s):  
J. A. Stephen Viggiano

Causes of numerical pathology in formulas for reflectance factor (R), transmittance factor (T ), and reflectance factor over a perfectly black background (R 0 ) under the Kubelka–Munk model are posited, and alternate formulas believed less prone to these pathologies are introduced. Suggestions are offered not only for R, T , and R 0 , but also for intermediate or adjunct quantities used in the main formulas. Computational experiments were performed to verify that the new models produce the same results as the existing ones under non-pathological conditions, exhibit acceptable levels of precision in a customary floating-point environment, and are more robust with respect to edge cases where an input quantity is zero. The new formulas performed well, with some evidence that the new hyperbolic forms provide better accuracy than their exponential counterparts.


2020 ◽  
Author(s):  
KyeongMin Cha

BACKGROUND It is difficult to develop a drug image recognition system due to the difference of the pill color influenced by external environmental factors such as the illumination or presence of flash. OBJECTIVE In this study, we wanted to see how the difference in color between the reference image and the real-world image affects the accuracy in pill recognition under 12 real-world conditions according to the background colors, presence of flash, and exposure values (EV). METHODS We used 19 medications with different features of colors, shapes, and dosages. The average color difference was calculated based on the color distance between the reference image and the real-world image. RESULTS In the case of the black background, as the exposure value lowered, the accuracy of top-1 and top-5 increased independently of the presence of flash. The top-5 accuracy in black background increased from 26.8% to 72.6% with the flash on and from 29.5% to 76.8% with the flash off as EV decreased as well. On the other hand, top-5 accuracy was 62.1% to 78.4% in white background with the flash on. The best top-1 accuracy was 51.1 % in the white background, flash on, and EV+2.0. The best top-5 accuracy was 78.4% in the white background, flash on, and EV0. CONCLUSIONS The accuracy generally increased as the color difference decreased except in the case of black background and EV-2.0. This study reveals that the background colors, presence of flash, and exposure values in real-world conditions are important factors affecting the performance of a pill recognition model.


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