昆虫对偏振光的响应及感受机理研究进展

偏振光是不同于普通光源的一种光, 常指光矢量在某一个方向振动的光波, 可分为线性偏振光、 圆偏振光和椭圆偏振光等。目前已经发现自然界的偏振光影响许多昆虫的行为, 如西方蜜蜂Apis mellifera的飞行导航、 蛱蝶Heliconius cydno chioneus的觅偶、 凤蝶Papilio aegeus产卵场所的选择等。金龟子对圆偏振光的反射可以作为一种分类的性状。昆虫复眼背部边缘区域（dorsal rim area, DRA）小眼是感受偏振光的主要器官, 电生理学研究表明前视神经节是蝗虫偏振视觉通路的一部分。在匈牙利, 已经开始利用偏振光研制步甲等昆虫的诱捕器。     

Guiding cellular activity with polarized light

Actin, cytoskeleton protein forming microfilaments, play a crucial role in cellular motility. Here we show that exposure to very low levels of polarized light guide their orientation in‐vivo within the live cell. Using a simple model to describe the role of actin‐filament orientation in directional cellular motion, we demonstrate that the actin polymerization/depolymerization mechanism develops primarily along this direction and, under certain conditions, can lead to guidance of the cell movement. Our results also show a dose dependent increase in actin activity in direct correspondence to the level of laser irradiance. We found that total expression of Tau protein, which stabilize microtubules, was decreased by the irradiance, indicating that exposure to the light may change the activity of kinase, leading to increased cell activity.

     

Stimulation of glucose oxidase with white linearly polarized light

Glucose oxidase (GOD) was illuminated with white linearly polarized light (WLPL). The enzyme was illuminated at room temperature in separate vessels then admixed to a reactor filled with D ‐glucose. The illumination of the enzyme for 60 min at 25–30°C and pH 6.5–7.0 provided its superior stimulation as proven in the oxidation of β‐D ‐glucose. Lyophilization of the illuminated enzyme reduced its activity by, approximately, 30%. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010     

Instant polarized light microscopy for imaging collagen microarchitecture and dynamics

Collagen fibers are a primary load-bearing component of connective tissues and are therefore central to tissue biomechanics and pathophysiology. Understanding collagen architecture and behavior under dynamic loading requires a quantitative imaging technique with simultaneously high spatial and temporal resolutions. Suitable techniques are thus rare and often inaccessible. In this study, we present instant polarized light microscopy (IPOL), in which a single snapshot image encodes information on fiber orientation and retardance, thus fulfilling the requirement. We utilized both simulation and experimental data from collagenous tissues of chicken tendon, sheep eye, and porcine heart to evaluate the effectiveness of IPOL as a quantitative imaging technique. We demonstrate that IPOL allows quantitative characterization of micron-scale collagen fiber architecture at full camera frame rates (156 frames/second herein).     

Spatial orientation of social caterpillars is influenced by polarized light

Processionary caterpillars of Thaumetopoea pityocampa (in Europe) and Ochrogaster lunifer (in Australia) (Lepidoptera: Notodontidae) form single files of larvae crawling head-to-tail when moving to feeding and pupation sites. We investigated if the processions are guided by polarization vision. The heading orientation of processions could be manipulated with linear polarizing filters held above the leading caterpillar. Exposure to changes in the angle of polarization around the caterpillars resulted in corresponding changes in heading angles. Anatomical analysis indicated specializations for polarization vision of stemma I in both species. Stemma I has a rhabdom with orthogonal and aligned microvilli, and an opaque and rugged surface, which are optimizations for skylight polarization vision, similar to the dorsal rim of adult insects. Stemmata II-VI have a smooth and shiny surface and lobed rhabdoms with non-orthogonal and non-aligned microvilli; they are thus optimized for general vision with minimal polarization sensitivity. Behavioural and anatomical evidence reveal that polarized light cues are important for larval orientation and can be robustly detected with a simple visual system.     

Formation of cyclodextrins with cyclodextrin glucosyltransferase stimulated with polarized light

After illumination with white, linearly polarized light (WLPL), cyclodextrin glycosyltransferase produced mixture of α‐, β‐, and γ‐cyclodextrins (CD) with higher overall yield than did that enzyme when nonilluminated. The illumination also influenced the ratio of those CD and that effect depended on concentration of enzyme and illumination time. At a high enzyme concentration (0.64 U/cm³), regardless the illumination time, formation of β‐CD predominated. The highest yield of β‐CD was afforded after 1 h illumination and 2 h illumination led to a significant increase in the yield of γ‐CD. Three‐month storage of enzyme illuminated with WLPL did not reduce its enhanced activity. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009     

Behavioural and physiological mechanisms of polarized light sensitivity in birds

Polarized light (PL) sensitivity is relatively well studied in a large number of invertebrates and some fish species, but in most other vertebrate classes, including birds, the behavioural and physiological mechanism of PL sensitivity remains one of the big mysteries in sensory biology. Many organisms use the skylight polarization pattern as part of a sun compass for orientation, navigation and in spatial orientation tasks. In birds, the available evidence for an involvement of the skylight polarization pattern in sun-compass orientation is very weak. Instead, cue-conflict and cue-calibration experiments have shown that the skylight polarization pattern near the horizon at sunrise and sunset provides birds with a seasonally and latitudinally independent compass calibration reference. Despite convincing evidence that birds use PL cues for orientation, direct experimental evidence for PL sensitivity is still lacking. Avian double cones have been proposed as putative PL receptors, but detailed anatomical and physiological evidence will be needed to conclusively describe the avian PL receptor. Intriguing parallels between the functional and physiological properties of PL reception and light-dependent magnetoreception could point to a common receptor system.     

铜绿丽金龟对圆偏振光的行为和视网膜电位反应

圆偏振光在地球环境中是很少见的, 来自珠宝金龟甲体壁反射圆偏振光是稀有的自然资源之一。铜绿丽金龟Anomala corpulenta Motschulsky与其他珠宝金龟甲一样其体壁能够反射左旋圆偏振光。为了解铜绿丽金龟对圆偏振光的感知能力, 本研究利用室内行为、 田间诱集与视网膜电位(electroretinogram, ERG)等方法研究了铜绿丽金龟对圆偏振光的响应。室内行为研究结果表明, 铜绿丽金龟对左旋圆偏振光与右旋圆偏振光的趋光反应明显低于非偏振光, 避光反应明显大于非偏振光, 且对左旋圆偏振光的趋、 避光反应均大于右旋圆偏振光。田间选择试验结果显示, 铜绿丽金龟对左旋和右旋圆偏振光的选择明显低于非偏振光, 且右旋大于左旋圆偏振光。电生理学研究结果表明, 左旋和右旋圆偏振光与非偏振光一样, 均能引发铜绿丽金龟的ERG反应, 且无明显差异。这些研究结果表明铜绿丽金龟体壁能够反射产生左旋圆偏振光, 且能够感知和区分左旋和右旋圆偏振光, 说明铜绿丽金龟存在偏振视觉, 具有圆偏振光敏感性。     

麦红吸浆虫成虫对线偏振光的趋性

【目的】本研究旨在探索麦红吸浆虫Sitodiplosis mosellana对线偏振光的趋光效果。【方法】在室内采用自行设计的Y-型管装置,测试了麦红吸浆虫成虫对线偏振光与非偏振光的选择差异,并利用线偏振光诱捕装置进行了田间对比试验。【结果】结果显示,麦红吸浆虫成虫对线偏振光与非偏振光的趋光选择率分别为47.23%和20.31%,且二者之间差异显著;田间设置线偏振光与非偏振光紫外灯对麦红吸浆虫成虫的诱集量分别为:水平线偏振光(60.20)垂直线偏振光(37.60)非偏振光(25.60),且水平线偏振光与非偏振光源对麦红吸浆虫的诱集量具有显著差异。【结论】麦红吸浆虫对线偏振光具有较强的偏好性;水平线偏振紫外光诱捕装置与非偏振相比,对麦红吸浆虫有较强的诱集效果。     

Effect of granule size on the interference colors of starch in polarized light

Abstract

A Nikitin-Berek compensator tilted at 5.5° in a polarizing microscope was used to create a background second-order blue interference color against which starch granules were examined. A grating monochromator showed the first interference minimum of the background was at 590 nm. Starch granules have a radial molecular structure. Thus, some radii were in line with the axis of the compensator while others were across the compensator axis. Where radial birefringence counteracted the background birefringence, starch granules had two quadrants with a bright yellow first-order interference color. Where radial birefringence added to the background birefringence, there were two quadrants of second-order blue (higher than the background). In yellow quadrants where birefringence was reduced, the wavelength of the first interference minimum was reduced. In blue quadrants where birefringence was increased, the wavelength of the first interference minimum was increased. The extent to which the interference minimum of the background birefringence was shifted by starch granules was strongly dependent on the size of the starch granules. For yellow quadrants, the shifts were: r = ?0.87, P < 0.001, n = 22 for corn starch; r = ? 0.94, P <0.001, n = 22 for tapioca starch; and r = ?0.94, P <0.001, n = 12 for potato starch. For blue quadrants, the shifts were: r = 0.80, P < 0.001, n = 22 for corn; r = 0.81, P < 0.001, n = 22 for tapioca; and r = 0.93, P < 0.001, n = 16 for potato. When interference colors are used to evaluate starch granules, the granules should be similar in size or a correction must be made for granule size, and the Michel-Lévy chart of interference colors may be used to collect data subjectively.     

The Polarization of Light in a Tropical Rain Forest1

The light environment within forests presents complex patterns of brightness and spectral distribution of light. The polarized light field is no less complex. Using an imaging polarized light analyzer, we examined the natural fields of linearly polarized light in the tropical rain forest of Guatopo National Park, Venezuela. We found that the celestial polarization pattern remains visible underneath the forest canopy, although cloud and fog coverage may diffuse the light and reduce the polarization signal. We characterized several distinct light environments, each having a characteristic polarized light field. Furthermore, objects throughout the forest reflect light that is polarized in a predictable fashion depending upon the material, structure, and orientation of the reflecting surface. As a consequence of these patterns in the distribution of polarized light, some functions of polarization vision, such as navigation, must be limited to the spaces exposed to several extended portions of the sky, while others, such as remote sensing of surface orientation, object detection, and breaking of camouflage would be useful throughout the forest. The polarization of light adds another dimension to the complexity of the rain forest photic environment.     

Angular optimization for cancer identification with circularly polarized light

Depolarization of circularly polarized light scattered from biological tissues depends on structural changes in cell nuclei, which can provide valuable information for differentiating cancer tissues concealed in healthy tissues. In this study, we experimentally verified the possibility of cancer identification using scattering of circularly polarized light. We investigated the polarization of light scattered from a sliced biological tissue with various optical configurations. A significant difference between circular polarizations of light scattered from cancerous and healthy tissues is observed, which is sufficient to distinguish a cancerous region. The line-scanning experiments along a region incorporating healthy and cancerous parts indicate step-like behaviors in the degree of circular polarization corresponding to the state of tissues, whether cancerous or normal. An oblique and perpendicular incidence induces different resolutions for identifying cancerous tissues, which indicates that the optical arrangement can be selected according to the priority of resolution.     

A behavioral bioassay employing Daphnia for detection of sublethal effects: Response to polarized light

The swimming response of Daphnia pulicaria to polarized white light was examined. This response was employed as a behavioral bioassay to investigate the effects of sodium bromide (NaBr) on Daphnids physiology. The control response to linearly polarized white light involved an orientation at 90° to the e‐vector. With the addition of NaBr the response became more random. An EC₅₀ (concentration which eliminates the response in 50% of the test individuals) of 1.31 x 10^‐1 M NaBr was calculated using the statistic von Mises K. A possible mechanism to account for the toxicity of this mild sedative is the blocking by the bromide ion of chloride channels involved in transmitting nerve impulses.     

Scanning eye movements of the stomatopod crustacean,Neogonodactylus oerstedii,in polarized light fields

ABSTRACT

Stomatopod crustaceans have highly mobile, independently moving compound eyes that are sensitive to both linearly and circularly polarized light. They rotate their eyes to predictable angles when viewing a linearly polarized target, and they scan their eyes frequently to sample the visual field. Angles of scans are roughly perpendicular to the plane of the midband (a set of specialized parallel rows of equatorial ommatidia). We investigated scanning eye movements in one Caribbean stomatopod species (Neogonodactylus oerstedii) in uniform visual fields that were vertically polarized, horizontally polarized, or depolarized. We found that mean eye rotation and scan angles differed significantly among these different treatments. Average scan angles differed by 12°, being more horizontal in a vertically polarized field than in a horizontally polarized one, and also more horizontal in a vertically polarized field than in a depolarized field. Thus, these stomatopods adjusted visual scanning to the polarization of the visual environment.     

High‐resolution computational imaging of leaf hair patterning using polarized light microscopy

The leaf hairs (trichomes) on the aerial surface of many plant species play important roles in phytochemical production and herbivore protection, and have significant applications in the chemical and agricultural industries. Trichome formation in the model plant Arabidopsis thaliana also presents a tractable experimental system to study cell differentiation and pattern formation in plants and animals. Studies of this developmental process suggest that trichome positioning may be the result of a self‐forming pattern, emerging from a lateral inhibition mechanism determined by a network of regulatory factors. Critical to the continued success of these studies is the ability to quantitatively characterize trichome pattern phenotypes in response to mutations in the genes that regulate this process. Advanced protocols for the observation of changes in trichome patterns can be expensive and/or time consuming, and lack user‐friendly analysis tools. In order to address some of these challenges, we describe here a strategy based on polarized light microscopy for the quick and accurate measurement of trichome positions, and provide an online tool designed for the quantitative analyses of trichome number, density and patterning.     

Opposite effect of linearly polarized light on biosynthesis of interleukin-6 in a human B lymphoid cell line and peripheral human monocytes

The effects of linearly polarized light (LPL) and diffuse light (DL) on the in vitro interleukin-6 (IL-6) production in a human B lymphoma cell line (BMNH) and peripheral monocytes of healthy volunteers were compared. Our data show that there was a significant increase of IL-6 and IgM production in BMNH after exposure to LPL. The increase in IgM secretion was a consequence of its autocrine regulation by IL-6, since in the presence of anti-IL-6 and anti-IL-6 receptor antibodies the LPL-induced IgM secretion was abolished. In contrast to the stimulatory effect on B cells, exposure of human mononuclear phagocytes to LPL markedly reduced the production of IL-6 induced by subsequent stimulation of cells with bacterial endotoxin (LPS). The inhibition as most pronounced when suboptimal doses of LPS were applied. Under identical experimental conditions, DL had no effect on the IL-6 and IgM production of either B cells or monocytes.     

Spatial orientation of trout to partially polarized light

Summary The results of this study reveal that rainbow trout (Oncorhyncus mykiss formerly Salmo gairdneri) are capable of orienting to polarized light fields, and that the degree of polarization of the polarized light field affects the accuracy of orientation behavior. As previously shown, rainbow trout can accurately orient to a plane polarized light field after several sessions of food-rewarded training. The present data demonstrate that the accuracy of such orientation decreases the degree of polarization of the plane-polarized light field is lowered. In testing sessions, different concentrations of latex beads were introduced into a cuvette positioned below the light source to degrade the degree of polarization. There was evidence that trout could still detect the evector and use it in making orienting responses when the light was only 65% polarized. However, most of the test trout did not demonstrate orienting ability at levels of polarization below the 75% level.     

Snapshot polarized light scattering spectroscopy using spectrally-modulated polarimetry for early gastric cancer detection

Polarized light scattering spectroscopy (PLSS) is a promising optical technique developed for the detection of cancer, which extracts the single scattering light to infer morphological information of epithelial cells. However, traditional PLSS uses either a rotatable polarizer or two orthogonal polarizers to purify the single scattering light, which makes it complicated and challenged to build a PLSS endoscope. Herein, we propose a snapshot PLSS with a single optical path to directly get the single scattering light for the first time. The single scattering light is encoded using the spectrally - modulated polarimetry and decoded using the continuous slide iterative method. Both the polystyrene microsphere solutions and the ex vivo gastric cancer samples are used to verify the method. The experimental results of the snapshot PLSS are consistent well with that of the traditional PLSS. The proposed method has a potential for the building of snapshot PLSS endoscope systems in future.      

Circularly polarized light at the mirror: Caveats and opportunities

Moving from the simple concept that reflection onto a mirror surface changes the handedness of circularly polarized light, we describe what happens to the emergent polarization in two different cases after reflection on a back mirror. In the first case, a regular emitter is taken into account, where reflection has the effect to destroy the emergent polarization. In the second case, we show what could happen when a hypothetical apparently non-reciprocal emitting material undergoes a similar experiment. These simple concepts have important implications in the design of efficient circularly polarized emitting devices.