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Chingwen Wang - One of the best experts on this subject based on the ideXlab platform.
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neural processing of linearly and circularly Polarized Light signal in a mantis shrimp haptosquilla pulchella
The Journal of Experimental Biology, 2020Co-Authors: Tsyr Huei Chiou, Chingwen WangAbstract:ABSTRACT Stomatopods, or mantis shrimp, are the only animal group known to possess circular polarization vision along with linear polarization vision. By using the rhabdomere of a distally located photoreceptor as a wave retarder, the eyes of mantis shrimp are able to convert circularly Polarized Light into linearly Polarized Light. As a result, their circular polarization vision is based on the linearly Polarized Light-sensitive photoreceptors commonly found in many arthropods. To investigate how linearly and circularly Polarized Light signals might be processed, we presented a dynamic Polarized Light stimulus while recording from photoreceptors or lamina neurons in intact mantis shrimp Haptosquilla pulchella. The results indicate that all the circularly Polarized Light-sensitive photoreceptors also showed differential responses to the changing e-vector angle of linearly Polarized Light. When stimulated with linearly Polarized Light of varying e-vector angle, most photoreceptors produced a concordant sinusoidal response. In contrast, some lamina neurons doubled the response frequency in reacting to linearly Polarized Light. These responses resembled a rectified sum of two-channel linear polarization-sensitive photoreceptors, indicating that polarization visual signals are processed at or before the first optic lobe. Noticeably, within the lamina, there was one type of neuron that showed a steady depolarization response to all stimuli except right-handed circularly Polarized Light. Together, our findings suggest that, between the photoreceptors and lamina neurons, linearly and circularly Polarized Light may be processed in parallel and differently from one another.
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neural processing of linearly and circularly Polarized Light signal in a mantis shrimp haptosquilla pulchella
The Journal of Experimental Biology, 2020Co-Authors: Tsyr Huei Chiou, Chingwen WangAbstract:Stomatopods, or so-called mantis shrimps, are the only animal group known to possess circular polarization vision along with linear polarization vision. By using the rhabdomere of a distally located photoreceptor as a wave retarder, the eyes of mantis shrimps are able to convert circularly Polarized Light into linearly Polarized Light. As a result, their circular polarization vision is based on the linearly Polarized Light-sensitive photoreceptors commonly found in many arthropods. To investigate how linearly and circularly Polarized Light signals might be processed, we presented a dynamic Polarized Light stimulus while recording from photoreceptors or lamina neurons in intact mantis shrimps Haptosquilla pulchella. The results indicate that all the circularly Polarized Light-sensitive photoreceptors also showed differential responses to the changing e-vector angle of linearly Polarized Light. When stimulated with linearly Polarized Light of varying e-vector angle, most photoreceptors produced a concordant sinusoidal response. In contrast, some lamina neurons doubled the response frequency in reacting to linearly Polarized Light. These responses resembled a rectified sum of two-channel linear polarization-sensitive photoreceptors indicating that polarization visual signals are processed at or before the first optic lobe. Noticeably, within the lamina, there was one type of neuron that showed a steady depolarization response to all stimuli except right-handed circularly Polarized Light. Together, our findings suggest that, between the photoreceptors and lamina neurons, linearly and circularly Polarized Light may be processed in parallel and different from one another.
Alex I Vitkin - One of the best experts on this subject based on the ideXlab platform.
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Polarized Light imaging in biomedicine emerging mueller matrix methodologies for bulk tissue assessment
Journal of Biomedical Optics, 2015Co-Authors: Sanaz Alali, Alex I VitkinAbstract:Polarized Light point measurements and wide-field imaging have been studied for many years in an effort to develop accurate and information-rich tissue diagnostic methods. However, the extensive depolarization of Polarized Light in thick biological tissues has limited the success of these investigations. Recently, advances in technology and conceptual understanding have led to a significant resurgence of research activity in the promising field of bulk tissue polarimetry. In particular, with the advent of improved measurement, analysis, and interpretation methods, including Mueller matrix decomposition, new diagnostic avenues, such as quantification of microstructural anisotropy in bulk tissues, have been enabled. Further, novel technologies have improved the speed and the accuracy of polarimetric instruments for ex vivo and in vivo diagnostics. In this paper, we review some of the recent progress in tissue polarimetry, provide illustrative application examples, and offer an outlook to the future of Polarized Light imaging in bulk biological tissues.
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mueller matrix decomposition for Polarized Light assessment of biological tissues
Journal of Biophotonics, 2009Co-Authors: Nirmalya Ghosh, Michael F G Wood, Richard D Weisel, Brian C Wilson, Alex I VitkinAbstract:The Mueller matrix represents the transfer function of an optical system in its interactions with Polarized Light and its elements relate to specific biologically or clinically relevant properties. However, when many optical polarization effects occur simultaneously, the resulting matrix elements represent several "lumped" effects, thus hindering their unique interpretation. Currently, no methods exist to extract these individual properties in turbid media. Here, we present a novel application of a Mueller matrix decomposition methodology that achieves this objective. The methodology is validated theoretically via a novel Polarized-Light propagation model, and experimentally in tissue simulating phantoms. The potential of the approach is explored for two specific biomedical applications: monitoring of changes in myocardial tissues following regenerative stem cell therapy, through birefringence-induced retardation of the Light's linear and circular polarizations, and non-invasive blood glucose measurements through chirality-induced rotation of the Light's linear polarization. Results demonstrate potential for both applications.
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mueller matrix decomposition for Polarized Light assessment of biological tissues
Journal of Biophotonics, 2009Co-Authors: Nirmalya Ghosh, Michael F G Wood, Richard D Weisel, Brian C Wilson, Alex I VitkinAbstract:The Mueller matrix represents the transfer function of an optical system in its interactions with Polarized Light and its elements relate to specific biologically or clinically relevant properties. However, when many optical polarization effects occur simultaneously, the resulting matrix elements represent several “lumped” effects, thus hindering their unique interpretation. Currently, no methods exist to extract these individual properties in turbid media. Here, we present a novel application of a Mueller matrix decomposition methodology that achieves this objective. The methodology is validated theoretically via a novel Polarized-Light propagation model, and experimentally in tissue simulating phantoms. The potential of the approach is explored for two specific biomedical applications: monitoring of changes in myocardial tissues following regenerative stem cell therapy, through birefringence-induced retardation of the Light's linear and circular polarizations, and non-invasive blood glucose measurements through chirality-induced rotation of the Light's linear polarization. Results demonstrate potential for both applications. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Tsyr Huei Chiou - One of the best experts on this subject based on the ideXlab platform.
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neural processing of linearly and circularly Polarized Light signal in a mantis shrimp haptosquilla pulchella
The Journal of Experimental Biology, 2020Co-Authors: Tsyr Huei Chiou, Chingwen WangAbstract:ABSTRACT Stomatopods, or mantis shrimp, are the only animal group known to possess circular polarization vision along with linear polarization vision. By using the rhabdomere of a distally located photoreceptor as a wave retarder, the eyes of mantis shrimp are able to convert circularly Polarized Light into linearly Polarized Light. As a result, their circular polarization vision is based on the linearly Polarized Light-sensitive photoreceptors commonly found in many arthropods. To investigate how linearly and circularly Polarized Light signals might be processed, we presented a dynamic Polarized Light stimulus while recording from photoreceptors or lamina neurons in intact mantis shrimp Haptosquilla pulchella. The results indicate that all the circularly Polarized Light-sensitive photoreceptors also showed differential responses to the changing e-vector angle of linearly Polarized Light. When stimulated with linearly Polarized Light of varying e-vector angle, most photoreceptors produced a concordant sinusoidal response. In contrast, some lamina neurons doubled the response frequency in reacting to linearly Polarized Light. These responses resembled a rectified sum of two-channel linear polarization-sensitive photoreceptors, indicating that polarization visual signals are processed at or before the first optic lobe. Noticeably, within the lamina, there was one type of neuron that showed a steady depolarization response to all stimuli except right-handed circularly Polarized Light. Together, our findings suggest that, between the photoreceptors and lamina neurons, linearly and circularly Polarized Light may be processed in parallel and differently from one another.
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neural processing of linearly and circularly Polarized Light signal in a mantis shrimp haptosquilla pulchella
The Journal of Experimental Biology, 2020Co-Authors: Tsyr Huei Chiou, Chingwen WangAbstract:Stomatopods, or so-called mantis shrimps, are the only animal group known to possess circular polarization vision along with linear polarization vision. By using the rhabdomere of a distally located photoreceptor as a wave retarder, the eyes of mantis shrimps are able to convert circularly Polarized Light into linearly Polarized Light. As a result, their circular polarization vision is based on the linearly Polarized Light-sensitive photoreceptors commonly found in many arthropods. To investigate how linearly and circularly Polarized Light signals might be processed, we presented a dynamic Polarized Light stimulus while recording from photoreceptors or lamina neurons in intact mantis shrimps Haptosquilla pulchella. The results indicate that all the circularly Polarized Light-sensitive photoreceptors also showed differential responses to the changing e-vector angle of linearly Polarized Light. When stimulated with linearly Polarized Light of varying e-vector angle, most photoreceptors produced a concordant sinusoidal response. In contrast, some lamina neurons doubled the response frequency in reacting to linearly Polarized Light. These responses resembled a rectified sum of two-channel linear polarization-sensitive photoreceptors indicating that polarization visual signals are processed at or before the first optic lobe. Noticeably, within the lamina, there was one type of neuron that showed a steady depolarization response to all stimuli except right-handed circularly Polarized Light. Together, our findings suggest that, between the photoreceptors and lamina neurons, linearly and circularly Polarized Light may be processed in parallel and different from one another.
C Weisbuch - One of the best experts on this subject based on the ideXlab platform.
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high brightness Polarized Light emitting diodes
Light-Science & Applications, 2012Co-Authors: Elison Matioli, Stuart Brinkley, Kathryn M Kelchner, Shuji Nakamura, Steven P Denbaars, James S Speck, C WeisbuchAbstract:Researchers have designed a Light-emitting diode (LED) that produces bright directional Polarized blue Light. The device, developed at the University of California at Santa Barbara in the USA by Elison Matioli and collaborators, is based on a variant of the semiconductor gallium nitride, grown on a specifically crystal direction that yields emission of Polarized Light. The researchers improved Light extraction from the device by drilling aligned arrays of holes at precisely defined intervals into the substrate. This photonic crystal structure selectively enhances the emission of Polarized Light for particular emission angles by up to a factor of 1.8. High-brightness LEDs emitting Polarized Light are of interest for flat-screen displays, and also for household Lighting because they minimize the glare from Light reflections.
Uwe Homberg - One of the best experts on this subject based on the ideXlab platform.
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transformation of Polarized Light information in the central complex of the locust
The Journal of Neuroscience, 2009Co-Authors: Stanley Heinze, Sascha Gotthardt, Uwe HombergAbstract:Many insects perceive the E-vector orientation of Polarized skyLight and use it for compass navigation. In locusts, Polarized Light is detected by photoreceptors of the dorsal rim area of the eye. Polarized Light signals from both eyes are integrated in the central complex (CC), a group of neuropils in the center of the brain. Thirteen types of CC neuron are sensitive to dorsally presented, Polarized Light (POL-neurons). These neurons interconnect the subdivisions of the CC, particularly the protocerebral bridge (PB), the upper and lower divisions of the central body (CBU, CBL), and the adjacent lateral accessory lobes (LALs). All POL-neurons show polarization-opponency, i.e., receive excitatory and inhibitory input at orthogonal E-vector orientations. To provide physiological evidence for the direction of information flow through the polarization vision network in the CC, we analyzed the functional properties of the different cell types through intracellular recordings. Tangential neurons of the CBL showed highest signal-to-noise ratio, received either ipsilateral Polarized-Light input only or, together with CL1 columnar neurons, had eccentric receptive fields. Bilateral Polarized-Light inputs with zenith-centered receptive fields were found in tangential neurons of the PB and in columnar neurons projecting to the LALs. Together with other physiological parameters, these data suggest a flow of information from the CBL (input) to the PB and from here to the LALs (output). This scheme is supported by anatomical data and suggests transformation of purely sensory E-vector coding at the CC input stage to position-invariant coding of 360 degrees -compass directions at the output stage.
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spectral properties of identified Polarized Light sensitive interneurons in the brain of the desert locust schistocerca gregaria
The Journal of Experimental Biology, 2007Co-Authors: Michiyo Kinoshita, Keram Pfeiffer, Uwe HombergAbstract:Many migrating animals employ a celestial compass mechanism for spatial navigation. Behavioral experiments in bees and ants have shown that sun compass navigation may rely on the spectral gradient in the sky as well as on the pattern of sky polarization. While Polarized-Light sensitive interneurons (POL neurons) have been identified in the brain of several insect species, there are at present no data on the neural basis of coding the spectral gradient of the sky. In the present study we have analyzed the chromatic properties of two identified POL neurons in the brain of the desert locust. Both neurons, termed TuTu1 and LoTu1, arborize in the anterior optic tubercle and respond to unPolarized Light as well as to Polarized Light. We show here that the Polarized-Light response of both types of neuron relies on blue-sensitive photoreceptors. Responses to unPolarized Light depended on stimulus position and wavelength. Dorsal unPolarized blue Light inhibited the neurons, while stimulation from the ipsilateral side resulted in opponent responses to UV Light and green Light. While LoTu1 was inhibited by UV Light and was excited by green Light, one subtype of TuTu1 was excited by UV and inhibited by green Light. In LoTu1 the sensitivity to Polarized Light was at least 2 log units higher than the response to unPolarized Light stimuli. Taken together, the spatial and chromatic properties of the neurons may be suited to signal azimuthal directions based on a combination of the spectral gradient and the polarization pattern of the sky.
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neurons of the central complex of the locust schistocerca gregaria are sensitive to Polarized Light
The Journal of Neuroscience, 2002Co-Authors: Harm Vitzthum, Monika Muller, Uwe HombergAbstract:The central complex is a topographically ordered neuropil structure in the center of the insect brain. It consists of three major subdivisions, the upper and lower divisions of the central body and the protocerebral bridge. To further characterize the role of this brain structure, we have recorded the responses of identified neurons of the central complex of the desert locust Schistocerca gregaria to visual stimuli. We report that particular types of central complex interneurons are sensitive to Polarized Light. Neurons showed tonic responses to linearly Polarized Light with spike discharge frequencies depending on e-vector orientation. For all neurons tested, e-vector response curves showed polarization opponency. Receptive fields of the recorded neurons were in the dorsal field of view with some neurons receiving input from both compound eyes and others, only from the ipsilateral eye. In addition to responses to Polarized Light, certain neurons showed tonic spike discharges to unPolarized Light. Most polarization-sensitive neurons were associated with the lower division of the central body, but one type of neuron with arborizations in the upper division of the central body was also polarization-sensitive. Visual pathways signaling Polarized Light information to the central complex include projections via the anterior optic tubercle. Considering the receptive fields of the neurons and the biological significance of Polarized Light in insects, the central complex might serve a function in sky compass-mediated spatial navigation of the animals.
