scholarly journals Behavioural red-light sensitivity in fish according to the optomotor response

2021 ◽  
Vol 8 (8) ◽  
pp. 210415
Author(s):  
Megumi Matsuo ◽  
Yasuhiro Kamei ◽  
Shoji Fukamachi
Keyword(s):  
Spectral Sensitivity ◽  
Fish Species ◽  
Near Infrared ◽  
Red Light ◽  
Light Sensitivity ◽  
Visual Sensitivity ◽  
Infrared Light ◽  
Optomotor Response ◽  
Optokinetic Response ◽  
Cone Opsin

Various procedures have been adopted to investigate spectral sensitivity of animals, e.g. absorption spectra of visual pigments, electroretinography, optokinetic response, optomotor response (OMR) and phototaxis. The use of these techniques has led to various conclusions about animal vision. However, visual sensitivity should be evaluated consistently for a reliable comparison. In this study, we retrieved behavioural data of several fish species using a single OMR procedure and compared their sensitivities to near-infrared light. Besides cavefish that lack eyes, some species were not appropriate for the OMR test because they either stayed still or changed swimming direction frequently. Eight of 13 fish species tested were OMR positive. Detailed analyses using medaka, goldfish, zebrafish, guppy, stickleback and cichlid revealed that all the fish were sensitive to light at a wavelength greater than or equal to 750 nm, where the threshold wavelengths varied from 750 to 880 nm. Fish opsin repertoire affected the perception of red light. By contrast, the copy number of long-wavelength-sensitive ( LWS ) genes did not necessarily improve red-light sensitivity. While the duplication of LWS and other cone opsin genes that has occurred extensively during fish evolution might not aid increasing spectral sensitivity, it may provide some other advantageous ophthalmic function, such as enhanced spectral discrimination.

Single red emission from upconverting ZnGa2O4:Yb,Er nanoparticles co-doped by Cr3+

2020 ◽  
Vol 8 (19) ◽  
pp. 6370-6379 ◽  
Author(s):  
Bhupendra B. Srivastava ◽  
Santosh K. Gupta ◽  
Yuanbing Mao
Keyword(s):  
Hydrothermal Method ◽  
Near Infrared ◽  
Red Light ◽  
Infrared Light ◽  
Near Infrared Light ◽  
Red Emission ◽  
Co Doped

ZnGa2O4:Yb3+,Er3+,Cr3+ nanoparticles synthesized by a hydrothermal method and further annealing emit bright singular red light under 980 nm excitation and near-infrared light under 254 nm excitation.

scholarly journals Transcriptome analysis of human dermal fibroblasts following red light phototherapy

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Evan Austin ◽  
Eugene Koo ◽  
Alexander Merleev ◽  
Denis Torre ◽  
Alina Marusina ◽  
...  
Keyword(s):  
Near Infrared ◽  
Red Light ◽  
Cellular Responses ◽  
Dermal Fibroblasts ◽  
Infrared Light ◽  
Human Dermal Fibroblasts ◽  
Collagen Deposition ◽  
Fibroblast Proliferation ◽  
Cellular Mechanisms ◽  
Matrix Metalloproteinase 1

AbstractFibrosis occurs when collagen deposition and fibroblast proliferation replace healthy tissue. Red light (RL) may improve skin fibrosis via photobiomodulation, the process by which photosensitive chromophores in cells absorb visible or near-infrared light and undergo photophysical reactions. Our previous research demonstrated that high fluence RL reduces fibroblast proliferation, collagen deposition, and migration. Despite the identification of several cellular mechanisms underpinning RL phototherapy, little is known about the transcriptional changes that lead to anti-fibrotic cellular responses. Herein, RNA sequencing was performed on human dermal fibroblasts treated with RL phototherapy. Pathway enrichment and transcription factor analysis revealed regulation of extracellular matrices, proliferation, and cellular responses to oxygen-containing compounds following RL phototherapy. Specifically, RL phototherapy increased the expression of MMP1, which codes for matrix metalloproteinase-1 (MMP-1) and is responsible for remodeling extracellular collagen. Differential regulation of MMP1 was confirmed with RT-qPCR and ELISA. Additionally, RL upregulated PRSS35, which has not been previously associated with skin activity, but has known anti-fibrotic functions. Our results suggest that RL may benefit patients by altering fibrotic gene expression.

scholarly journals Anti-Biofilm Property of Bioactive Upconversion Nanocomposites Containing Chlorin e6 against Periodontal Pathogens

Molecules ◽  
2019 ◽  
Vol 24 (15) ◽  
pp. 2692 ◽  
Author(s):  
Tianshou Zhang ◽  
Di Ying ◽  
Manlin Qi ◽  
Xue Li ◽  
Li Fu ◽  
...  
Keyword(s):  
Periodontal Disease ◽  
Near Infrared ◽  
Periodontal Diseases ◽  
Upconversion Luminescence ◽  
Red Light ◽  
Fusobacterium Nucleatum ◽  
Infrared Light ◽  
Periodontal Pathogens ◽  
Hydrophobic Chain ◽  
Novel Strategy

Photodynamic therapy (PDT) based periodontal disease treatment has received extensive attention. However, the deep tissue location of periodontal plaque makes the conventional PDT encounter a bottleneck. Herein, upconversion fluorescent nanomaterial with near-infrared light excitation was introduced into the treatment of periodontal disease, overcoming the limited tissue penetration depth of visible light in PDT. Photosensitizer Ce6 molecules were combined with upconversion nanoparticles (UCNPs) NaYF4:Yb,Er with a novel strategy. The hydrophobic UCNPs were modified with amphiphilic silane, utilizing the hydrophobic chain of the silane to bind to the hydrophobic groups of the UCNPs through a hydrophobic-hydrophobic interaction, and the Ce6 molecules were loaded in this hydrophobic layer. This achieves both the conversion of the hydrophobic to the hydrophilic surface and the loading of the oily photosensitizer molecules. Because the excitation position of the Ce6 molecule is in the red region, Mn ions were doped to enhance red light, and thus the improved PDT function. This Ce6 loaded UCNPs composites with efficient red upconversion luminescence show remarkable bacteriological therapeutic effect on Porphyromonas gingivalis, Prevotella intermedia and Fusobacterium nucleatum and the corresponding biofilms under 980 nm irradiation, indicating a high application prospect in the treatment of periodontal diseases.

scholarly journals A Novel Illumination Compensation Technique for Multi-Spectral Imaging in NDVI Detection

Sensors ◽  
2019 ◽  
Vol 19 (8) ◽  
pp. 1859
Author(s):  
Rui Jiang ◽  
Pei Wang ◽  
Yan Xu ◽  
Zhiyan Zhou ◽  
Xiwen Luo ◽  
...  
Keyword(s):  
Light Source ◽  
Radiation Intensity ◽  
Near Infrared ◽  
Imaging System ◽  
Red Light ◽  
Spectral Imaging ◽  
Constant Current ◽  
Infrared Light ◽  
Ndvi Index ◽  
Led Arrays

To overcome the dependence on sunlight of multi-spectral cameras, an active light source multi-spectral imaging system was designed and a preliminary experimental study was conducted at night without solar interference. The system includes an active light source and a multi-spectral camera. The active light source consists of four integrated LED (Light Emitting Diode) arrays and adjustable constant current power supplies. The red LED arrays and the near-infrared LED arrays are each driven by an independently adjustable constant current power supply. The center wavelengths of the light source are 668 nm and 840 nm, which are consistent with that of filter lens of the Rededge-M multi-spectral camera. This paper shows that the radiation intensity measured is proportional to the drive current and is inversely proportional to the radiation distance, which is in accordance with the inverse square law of light. Taking the inverse square law of light into account, a radiation attenuation model was established based on the principle of image system and spatial geometry theory. After a verification test of the radiation attenuation model, it can be concluded that the average error between the radiation intensity obtained using this model and the actual measured value using a spectrometer is less than 0.0003 w/m2. In addition, the fitting curve of the multi-spectral image grayscale digital number (DN) and reflected radiation intensity at the 668 nm (Red light) is y = −3484230x2 + 721083x + 5558, with a determination coefficient of R2 = 0.998. The fitting curve with the 840 nm (near-infrared light) is y = 491469.88x + 3204, with a determination coefficient of R2 = 0.995, so the reflected radiation intensity on the plant canopy can be calculated according to the grayscale DN. Finally, the reflectance of red light and near-infrared light can be calculated, as well as the Normalized Difference Vegetation Index (NDVI) index. Based on the above model, four plants were placed at 2.85 m away from the active light source multi-spectral imaging system for testing. Meanwhile, NDVI index of each plant was measured by a Greenseeker hand-held crop sensor. The results show that the data from the two systems were linearly related and correlated with a coefficient of 0.995, indicating that the system in this article can effectively detect the vegetation NDVI index. If we want to use this technology for remote sensing in UAV, the radiation intensity attenuation and working distance of the light source are issues that need to be considered carefully.

Green and Far-Red-Light Induced Electron Injection from Perylene Bisimide to Wide Bandgap Semiconductor Nanocrystals with Stepwise Two-Photon Absorption Process

Nanoscale ◽  
2021 ◽  
Author(s):  
Daisuke Yoshioka ◽  
Daiki Fukuda ◽  
Yoichi Kobayashi
Keyword(s):  
Near Infrared ◽  
Semiconductor Nanocrystals ◽  
Red Light ◽  
Wide Bandgap ◽  
Photochemical Reactions ◽  
Photon Absorption ◽  
Infrared Light ◽  
Two Photon Absorption ◽  
Perylene Bisimide ◽  
Two Photon

Stepwise two-photon absorption (2PA) processes are becoming an important technique because it can achieve high reductive photochemical reactions with visible and near infrared light and intensity-gated high spatiotemporal selectivity with...

Restoring light sensitivity using tunable near-infrared sensors

Science ◽  
2020 ◽  
Vol 368 (6495) ◽  
pp. 1108-1113 ◽  
Author(s):  
Dasha Nelidova ◽  
Rei K. Morikawa ◽  
Cameron S. Cowan ◽  
Zoltan Raics ◽  
David Goldblum ◽  
...  
Keyword(s):  
Retinal Degeneration ◽  
Cortical Neurons ◽  
Near Infrared ◽  
Transient Receptor Potential ◽  
Trp Channels ◽  
Receptor Potential ◽  
Light Sensitivity ◽  
Infrared Light ◽  
Temperature Sensitive ◽  
Near Infrared Light

Enabling near-infrared light sensitivity in a blind human retina may supplement or restore visual function in patients with regional retinal degeneration. We induced near-infrared light sensitivity using gold nanorods bound to temperature-sensitive engineered transient receptor potential (TRP) channels. We expressed mammalian or snake TRP channels in light-insensitive retinal cones in a mouse model of retinal degeneration. Near-infrared stimulation increased activity in cones, ganglion cell layer neurons, and cortical neurons, and enabled mice to perform a learned light-driven behavior. We tuned responses to different wavelengths, by using nanorods of different lengths, and to different radiant powers, by using engineered channels with different temperature thresholds. We targeted TRP channels to human retinas, which allowed the postmortem activation of different cell types by near-infrared light.

Fluorescent proteins for in vivo imaging, where's the biliverdin?

2020 ◽  
Vol 48 (6) ◽  
pp. 2657-2667
Author(s):  
Felipe Montecinos-Franjola ◽  
John Y. Lin ◽  
Erik A. Rodriguez
Keyword(s):  
Hydrogen Peroxide ◽  
In Vivo Imaging ◽  
Near Infrared ◽  
Fluorescent Protein ◽  
Fluorescent Proteins ◽  
Fluorescent Imaging ◽  
Infrared Light ◽  
Red Fluorescent Protein ◽  
Color Palette

Noninvasive fluorescent imaging requires far-red and near-infrared fluorescent proteins for deeper imaging. Near-infrared light penetrates biological tissue with blood vessels due to low absorbance, scattering, and reflection of light and has a greater signal-to-noise due to less autofluorescence. Far-red and near-infrared fluorescent proteins absorb light >600 nm to expand the color palette for imaging multiple biosensors and noninvasive in vivo imaging. The ideal fluorescent proteins are bright, photobleach minimally, express well in the desired cells, do not oligomerize, and generate or incorporate exogenous fluorophores efficiently. Coral-derived red fluorescent proteins require oxygen for fluorophore formation and release two hydrogen peroxide molecules. New fluorescent proteins based on phytochrome and phycobiliproteins use biliverdin IXα as fluorophores, do not require oxygen for maturation to image anaerobic organisms and tumor core, and do not generate hydrogen peroxide. The small Ultra-Red Fluorescent Protein (smURFP) was evolved from a cyanobacterial phycobiliprotein to covalently attach biliverdin as an exogenous fluorophore. The small Ultra-Red Fluorescent Protein is biophysically as bright as the enhanced green fluorescent protein, is exceptionally photostable, used for biosensor development, and visible in living mice. Novel applications of smURFP include in vitro protein diagnostics with attomolar (10−18 M) sensitivity, encapsulation in viral particles, and fluorescent protein nanoparticles. However, the availability of biliverdin limits the fluorescence of biliverdin-attaching fluorescent proteins; hence, extra biliverdin is needed to enhance brightness. New methods for improved biliverdin bioavailability are necessary to develop improved bright far-red and near-infrared fluorescent proteins for noninvasive imaging in vivo.

Catalyst Halogenation Enables Rapid and Efficient Polymerizations with Visible to Near-Infrared Light

2020 ◽  
Author(s):  
Alex Stafford ◽  
Dowon Ahn ◽  
Emily Raulerson ◽  
Kun-You Chung ◽  
Kaihong Sun ◽  
...  
Keyword(s):  
Near Infrared ◽  
Transient Absorption ◽  
Reaction Times ◽  
Infrared Light ◽  
Structure Property ◽  
Light Emitting ◽  
Structure Property Relationships ◽  
Nir Light ◽  
Light Intensities ◽  
Emission Quenching

Driving rapid polymerizations with visible to near-infrared (NIR) light will enable nascent technologies in the emerging fields of bio- and composite-printing. However, current photopolymerization strategies are limited by long reaction times, high light intensities, and/or large catalyst loadings. Improving efficiency remains elusive without a comprehensive, mechanistic evaluation of photocatalysis to better understand how composition relates to polymerization metrics. With this objective in mind, a series of methine- and aza-bridged boron dipyrromethene (BODIPY) derivatives were synthesized and systematically characterized to elucidate key structure-property relationships that facilitate efficient photopolymerization driven by visible to NIR light. For both BODIPY scaffolds, halogenation was shown as a general method to increase polymerization rate, quantitatively characterized using a custom real-time infrared spectroscopy setup. Furthermore, a combination of steady-state emission quenching experiments, electronic structure calculations, and ultrafast transient absorption revealed that efficient intersystem crossing to the lowest excited triplet state upon halogenation was a key mechanistic step to achieving rapid photopolymerization reactions. Unprecedented polymerization rates were achieved with extremely low light intensities (< 1 mW/cm<sup>2</sup>) and catalyst loadings (< 50 μM), exemplified by reaction completion within 60 seconds of irradiation using green, red, and NIR light-emitting diodes.

An ordered copper nanowell-array film with near-perfect broadband absorption from ultraviolet to near-infrared light

2020 ◽  
Vol 59 (11) ◽  
pp. 110906
Author(s):  
Juan Shen ◽  
Yong Ren ◽  
Xinxin Zhu ◽  
Min Mao ◽  
Quan Zhou ◽  
...  
Keyword(s):  
Near Infrared ◽  
Infrared Light ◽  
Near Infrared Light ◽  
Broadband Absorption
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