scholarly journals C. elegans discriminate colors without eyes or opsins

2016 ◽  
Author(s):  
D. Dipon Ghosh ◽  
Xin Jin ◽  
Michael Nitabach
Keyword(s):  
Detection System ◽  
Color Discrimination ◽  
Blue Pigment ◽  
Light Sources ◽  
Amber Light ◽  
C Elegans ◽  
Color Detection ◽  
Psychophysical Studies ◽  
Light Guides ◽  
Foraging Decision

AbstractHere we establish that, contrary to expectations, Caenorhabditis elegans nematode worms possess a color discrimination system despite lacking any opsin or other known visible light photoreceptor genes. We found that white light guides C. elegans foraging decisions away from harmful bacteria that secrete a blue pigment toxin. Absorption of amber light by this blue pigment toxin alters the color of light sensed by the worm, and thereby triggers an increase in avoidance. By combining narrow-band blue and amber light sources, we demonstrated that detection of the specific blue:amber ratio by the worm guides its foraging decision. These behavioral and psychophysical studies thus establish the existence of a color detection system that is distinct from those of other animals.

scholarly journals C. elegans discriminates colors to guide foraging

Science ◽  
2021 ◽  
Vol 371 (6533) ◽  
pp. 1059-1063 ◽  
Author(s):  
D. Dipon Ghosh ◽  
Dongyeop Lee ◽  
Xin Jin ◽  
H. Robert Horvitz ◽  
Michael N. Nitabach
Keyword(s):  
Stress Response ◽  
Cellular Stress ◽  
Color Discrimination ◽  
Cellular Stress Response ◽  
Blue Pigment ◽  
Natural Environments ◽  
C Elegans ◽  
Evolutionarily Conserved ◽  
Foraging Decisions ◽  
Light Guides

Color detection is used by animals of diverse phyla to navigate colorful natural environments and is thought to require evolutionarily conserved opsin photoreceptor genes. We report that Caenorhabditis elegans roundworms can discriminate between colors despite the fact that they lack eyes and opsins. Specifically, we found that white light guides C. elegans foraging decisions away from a blue-pigment toxin secreted by harmful bacteria. These foraging decisions are guided by specific blue-to-amber ratios of light. The color specificity of color-dependent foraging varies notably among wild C. elegans strains, which indicates that color discrimination is ecologically important. We identified two evolutionarily conserved cellular stress response genes required for opsin-independent, color-dependent foraging by C. elegans, and we speculate that cellular stress response pathways can mediate spectral discrimination by photosensitive cells and organisms—even by those lacking opsins.

Development of a three-dimensional color rendition space for tunable solid-state light sources

2021 ◽  
Vol 2021 (29) ◽  
pp. 136-140
Author(s):  
Dorukalp Durmus
Keyword(s):  
Solid State ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Color Discrimination ◽  
Continuous Measure ◽  
Light Sources ◽  
Vast Number ◽  
Lighting Systems ◽  
Single Number

The quality of building electric lighting systems can be assessed using color rendition metrics. However, color rendition metrics are limited in quantifying tunable solid-state light sources, since tunable lighting systems can generate a vast number of different white light spectra, providing flexibility in terms of color quality and energy efficiency. Previous research suggests that color rendition is multi-dimensional in nature, and it cannot be simplified to a single number. Color shifts under a test light source in comparison to a reference illuminant, changes in color gamut, and color discrimination are important dimensions of the quality of electric light sources, which are not captured by a single-numbered metric. To address the challenges in color rendition characterization of modern solid-state light sources, the development of a multi-dimensional color rendition space is proposed. The proposed continuous measure can quantify the change in color rendition ability of tunable solid-state light devices with caveats. Future work, discretization of the continuous color rendition space, will be carried out to address the shortcomings of a continuous three-dimensional space.

Cantilever enhanced based photoacoustic detection of SF6 decomposition component SO2 using UV LED

Sensor Review ◽  
2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Tunan Chen ◽  
Fengxiang Ma ◽  
Yue Zhao ◽  
Zhenghai Liao ◽  
Zongjia Qiu ◽  
...  
Keyword(s):  
Detection Limit ◽  
Detection System ◽  
Light Sources ◽  
Photoacoustic Detection ◽  
Low Light ◽  
Power Requirement ◽  
Light Power ◽  
Content Type ◽  
Uv Led ◽  
Sf6 Decomposition

Purpose This paper aims to establish a photoacoustic detection system for SO2 using UV-LED and testify its feasibility for sensitive measurement. The work in this paper can avoid potential crossover interference in infrared (IR) range and also balance the capability and cost of feasible excitation for photoacoustic detection system. Design/methodology/approach In this experimental work, a cantilever-enhanced–based photoacoustic SO2 detection system using an ultraviolet (UV) LED light source with a light power of 4 mW as the excitation was established. Findings A feasible photoacoustic detection system for SO2 using UV-LED was established. Experimental results demonstrate that the detection limit of the system can reach the level of 0.667 ppm, which can serve as a reference for the application of PAS in insulation fault diagnosis. Originality/value This work investigated the potential of using ultraviolet photoacoustic spectroscopy to detect trace SO2, which provided an ideal replacement of infrared-laser-based detection system. In this paper, a photoacoustic detection system using LED with a low light power was established. Low light power requirement can expand the options of light sources accordingly. In this paper, the absorption characteristics of SO2 in the presented detection system and ultraviolet range were studied. And the detection limit of the presented system was given. Both of which can provide reference to SO2 detection in ambient SF6.

scholarly journals Design and Research of a Color Discrimination Method for Polycrystalline Silicon Cells Based on Laser Detection System

2019 ◽  
Vol 9 (20) ◽  
pp. 4468
Author(s):  
Zijian Chen ◽  
Shiyu Wang ◽  
Lian Zhang ◽  
Zenghong Ma
Keyword(s):  
Polycrystalline Silicon ◽  
Detection System ◽  
Measurement Data ◽  
Optical Power ◽  
Color Discrimination ◽  
Laser Detection ◽  
Coaxial System ◽  
Power Meter ◽  
Optical Shutters ◽  
Silicon Cell

In this paper, a method of color discrimination based on sample sensitivity to light wavelength is proposed based on the reflection spectra of a large number of samples and the statistical calculation of the measurement data. A laser detection system is designed to realize the color discrimination. For the color discrimination of polycrystalline silicon cells, the most sensitive wavelength, 434 nm, and the least sensitive wavelength, 645 nm, of polycrystalline silicon cells is obtained according to this method. A laser detection system was built to measure the polycrystalline silicon cells. This system consists of two lasers, optical shutters, collimating beam expanding systems, an optical coaxial system, sample platform, collecting lens, and optical power meter or optical sensor. Two laser beams of different wavelengths are beamed coaxially through the optical coaxial system onto a polycrystalline silicon cell and are reflected or scattered. The reflected or scattered lights are collected through a lens with a high number aperture and received separately by the optical power meter. Then the color value of the polycrystalline silicon cell in this system is characterized by the ratio of light intensity data received. The system measured a large number of previous polycrystalline silicon cells to form the different color categories of polycrystalline silicon cells of this system in the computer database. When a new polycrystalline silicon cell is measured, the color discrimination system can automatically classify the new polycrystalline silicon cell to a certain color category in order to achieve color discrimination.

A LabVIEW Design for Frontal and Non-Frontal Human Face Detection System in Complex Background

2014 ◽  
Vol 490-491 ◽  
pp. 1259-1266 ◽  
Author(s):  
Muralindran Mariappan ◽  
Manimehala Nadarajan ◽  
Rosalyn R. Porle ◽  
Vigneswaran Ramu ◽  
Brendan Khoo Teng Thiam
Keyword(s):  
Face Detection ◽  
Skin Color ◽  
Detection Method ◽  
Detection System ◽  
Detection Algorithm ◽  
Biometric Technology ◽  
Main Challenge ◽  
Human Face Detection ◽  
Color Detection ◽  
Large Face

Biometric identification has advanced vastly since many decades ago. It became a blooming area for research as biometric technology has been used extensively in areas like robotics, surveillance, security and others. Face technology is more preferable due to its reliability and accuracy. By and large, face detection is the first processing stage that is performed before extending to face identification or tracking. The main challenge in face detection is the sensitiveness of the detection to pose, illumination, background and orientation. Thus, it is crucial to design a face detection system that can accommodate those problems. In this paper, a face detection algorithm is developed and designed in LabVIEW that is flexible to adapt changes in background and different face angle. Skin color detection method blending with edge and circle detection is used to improve the accuracy of face detected. The overall system designed in LabVIEW was tested in real time and it achieves accuracy about 97%.

scholarly journals Colorimeter Portable to Determine Ammonium Using to Manure Tetector

2021 ◽  
Vol 4 (2) ◽  
Author(s):  
Yohan Yohan ◽  
Fifit Astuti ◽  
Adimas Wicaksana
Keyword(s):  
Light Source ◽  
Calibration Curve ◽  
Detection System ◽  
Light Sources ◽  
Agricultural Application ◽  
Modular Data ◽  
Arduino Uno

Contruction of colorimeter and calibrationare presented in this paper. In this investigation involves design, detection system, and measurement.Colorimeter was fabricated in dimension (10 x 10 x 6)cm3 consist of light source, modular data, and transducer. The light sources were LEDs which responds of  wavelength peak at 467 nm on 0,141 W/m2. Arduino Uno R3 is used to data tabulation in calculate absorbance system with 1.8.5 sofware. Then transducer was used a LDR which useful for consider the light in sample and reference. The calibration curve of ammonium consentration shows  linierity range at 0.1 to 2 ppm with y = 0.0234x + 0.0905, R= 0.9716. The portable colorimeter was found accuration and precision about 88,7 % and 99,8%. the portabel colorimeter gives the best result in this investigation and use to fake manure detector in Agricultural application for domestic farmer.

scholarly journals Real-time Liquid Level and color Detection system using Image Processing

2018 ◽  
Vol 7 (4) ◽  
pp. 223
Author(s):  
Fars E. Samann
Keyword(s):  
Image Processing ◽  
Real Time ◽  
Chemical Reaction ◽  
Detection System ◽  
Chemical Study ◽  
Liquid Level ◽  
Average Accuracy ◽  
Color Detection ◽  
Liquid Level Detection

Detecting the level of the liquid is very essential for any chemical study in research labs. The objective of this paper is to design real-time liquid level detection system using image processing. Besides, this system is able to indicate the color of the liquid during chemical reaction. The proposed system was developed using vision assistant tools in LabVIEW and webcam. Regarding to webcam resolution, the average accuracy of the system is approximately 99%.

Structure for Efficiently Coupling Large Light Sources into Prism Light Guides

2000 ◽  
Vol 29 (2) ◽  
pp. 78-82 ◽  
Author(s):  
Peter Kan ◽  
L. Whitehead ◽  
S.J. Pojar ◽  
K.G. Kneipp
Keyword(s):  
Light Sources ◽  
Light Guides
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