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“Paris Profanely Illuminated” explores the “Circe” episode’s relation to 1920s Paris. It situates “Circe” at the origins of the Surrealist movement, showing the influence on the episode of the first Surrealist play, Apollinaire’s Les Mamelles de Tirésias, and the influence of the episode on the first Surrealist novel, Aragon’s Le Paysan de Paris. Tracing the influence of Joyce’s sentient thinking, it reexamines Benjamin’s reception of Surrealism, uncovering the influence of Joyce’s materially embedded reflection on the literary and conceptual experiments of a theorist who struggles with the nature of theory following the collapse of critical distance. The chapter examines Benjamin’s conceptions, in his 1929 essay “Surrealism: Last Snapshot of the European Intelligentsia” and the Arcades Project, of the profane illumination and the body-image space. It argues for the relevance of the nonrational, sensual modes of engagement Benjamin describes in the Arcades Project for the interpretation of Finnegans Wake.
LED illumination systems for fluorescence microscopy offer a wealth of benefits in comparison to traditional mercury and metal halide lamps, including ease of use, improved stability, and enhanced control. To fully realize these benefits, it is important to ensure that optical filters are configured correctly, which often can be confusing. However, without the correct filter configuration, experimental conditions can be suboptimal, and results may therefore be inaccurate. This article looks at optical filter setup in more depth, explaining the purpose and benefits of optimal LED filtering.
There is considerable debate as to the optimal light intensities for growing chickens. This is influencing regulations and industry practices. The present study examines the preference of broiler chickens for light intensity. A choice system was developed to allow determination of the preferences of broiler chickens for light intensity. This system had three light proof pens each with feeders or waterers but different light intensities. There was a connecting transit pen with a light intensity of 1 to 2 lux. This allowed birds access to the pens each with feeders or waterers. There were markedly more chickens observed in the pens each with feeders or waterers and a light intensity of 20 lux than 5 lux. Moreover, more feed was consumed in the 20 lux pens than 5 pens. There were also high numbers of chickens in the transit compartment with its low light intensity (1 to 2 lux) and no feeders or waterers. Broiler chickens exhibited a preference for 20 lux light intensity for feeding compared to 5 lux light intensity. The present study supports the view that there should be a light intensity of at least 20 lux for the areas around the feeders and also suggests that light intensity may be reduced in other areas for resting and other activities.
In this paper, a novel method for autonomous navigation for an extra-terrestrial body landing mission is proposed. Based on state-of-the-art crater detection and matching algorithms, a crater edge-based navigation method is formulated, in which solar illumination direction is adopted as a complementary optical cue to aid crater edge-based navigation when only one crater is available. To improve the pose estimation accuracy, a distributed Extended Kalman Filter (EKF) is developed to encapsulate the crater edge-based estimation approach. Finally, the effectiveness of proposed approach is validated by Monte Carlo simulations using a specifically designed planetary landing simulation toolbox.
Light sheet fluorescence microscopy (LSFM) allows for high-resolution three-dimensional imaging with minimal photo-damage. By viewing the sample from different directions, different regions of large specimens can be imaged optimally. Moreover, owing to their good spatial resolution and high signal-to-noise ratio, LSFM data are well suited for image deconvolution. Here we present the Huygens Fusion and Deconvolution Wizard, a unique integrated solution for restoring LSFM images, and show that improvements in signal and resolution of 1.5 times and higher are feasible.
Image segmentation is a key process in analyzing biological images. However, it is difficult to detect the differences between foreground and background when the image is unevenly illuminated. The unambiguous segmenting of multi-well plate microscopy images with various uneven illuminations is a challenging problem. Currently, no publicly available method adequately solves these various problems in bright-field multi-well plate images. Here, we propose a new method based on contrast values which removes the need for illumination correction. The presented method is effective enough to distinguish foreground and therefore a model organism (Caenorhabditis elegans) from an unevenly illuminated microscope image. In addition, the method also can solve a variety of problems caused by different uneven illumination scenarios. By applying this methodology across a wide range of multi-well plate microscopy images, we show that our approach can consistently analyze images with uneven illuminations with unparalleled accuracy and successfully solve various problems associated with uneven illumination. It can be used to process the microscopy images captured from multi-well plates and detect experimental subjects from an unevenly illuminated background.
Retinex theory explains how the human visual system perceives colors. The goal of retinex is to decompose the reflectance and the illumination from the given images and thereby compensating for non-uniform lighting. The existing methods for retinex usually use a single image with a fixed exposure to restore the reflectance of the image. In this paper, we propose a variational model for retinex problem by utilizing multi-exposure images of a given scene. The existence and uniqueness of the solutions of the proposed model have been elaborated. An alternating minimization method is constructed to solve the proposed model and its convergence is also demonstrated. The experimental results show that the proposed method is effective for reflectance recovery in retinex problem.
This article offers a new reading of Mozi’s chapter “Ming gui” 明鬼, conventionally considered as a treatise explaining Mohist ideas about ghosts and spirits, by shifting the focus from the ghosts (gui 鬼) to the concept of ming 明, interpreted as “sagely illumination.” The “Ming gui” chapter does not discuss ghosts in general, but instead a specific group of “punitive ghosts” who mete out punishments and rewards; it also shows that ming gui was not a group of ghosts particular to Mozi or Mohism alone, but was widespread in the beliefs and practices of the period. The execution of justice, which is the crucial concern of the treatise, depends on ming—the principle of justice and Heaven’s agency in human life—and not on ghosts. Ming also is an indispensable component of sagehood, as it is the illuminated sage ruler (ming jun 明君) who, on behalf of Heaven, ultimately metes out just punishments and rewards.
Image pre-processing is highly significant in automated analysis of microscopy images. In this work, non-uniform illumination correction has been attempted using the surface fitting method (SFM), multiple regression method (MRM), and bidirectional empirical mode decomposition (BEMD) in digital microscopy images of tuberculosis (TB). The sputum smear positive and negative images recorded under a standard image acquisition protocol were subjected to illumination correction techniques and evaluated by error and statistical measures. Results show that SFM performs more efficiently than MRM or BEMD. The SFM produced sharp images of TB bacilli with better contrast. To further validate the results, multifractal analysis was performed that showed distinct variation before and after implementation of illumination correction by SFM. Results demonstrate that after illumination correction, there is a 26% increase in the number of bacilli, which aids in classification of the TB images into positive and negative, as TB positivity depends on the count of bacilli.
In this paper, we study to use nonlocal bounded variation (NLBV) techniques to decompose an image intensity into the illumination and reflectance components. By considering spatial smoothness of the illumination component and nonlocal total variation (NLTV) of the reflectance component in the decomposition framework, an energy functional is constructed. We establish the theoretical results of the space of NLBV functions such as lower semicontinuity, approximation and compactness. These essential properties of NLBV functions are important tools to show the existence of solution of the proposed energy functional. Experimental results on both grey-level and color images are shown to illustrate the usefulness of the nonlocal total variation image decomposition model, and demonstrate the performance of the proposed method is better than the other testing methods.
Illumination using artificial light sources is common in these days. Many manufactures
are paying for the design of lamps depending on high efficacy and low UV hazards. This
research is focusing on the most useable lamps in the Egyptian markets; high pressure
mercury (HPM), metal Halide (MH), and high pressure sodium (HPS). A set up for relative
spectral power distribution based on single monochromator and UVA silicon detector for
absolute irradiance measurements are used. The absolute irradiance in (W/m2) in UVA region of the lamps and
their accompanied standard uncertainty are evaluated.
Several problematic specimens, especially when composed of a complex three-dimensional architecture or very high or ultralow ranges in regional thickness and density, can be observed in improved clarity and precision when universal variable brightfield–darkfield contrast (UVBDC) is used. In this method, two different partial images are optically superimposed and interfere with each other, contributing to complementary visual information: a brightfield and a darkfield image. These images can be generated with concentric-peripheral, paraxial, or axial illuminating light. In all variants, variable transitions between bright- and darkfield are achievable. By use of a pancratic condenser (zoom system), the illuminating light can be universally adjusted and optimally adapted to each type of specimen and each type of objective (glass and mirror lenses). The concentric-peripheral variant is preferably carried out with normal glass lenses, the axial variant with mirror lenses. Glass lenses can also be used for UVBDC based on axial or paraxial light when combined with a special contrast tube, which is described in detail. Which technical variant of UVBDC might lead to the best result may be determined by the particular properties of the specimen, but all techniques described promise significant improvements in image quality and visual information.
A new model of the Mars surface irradiation has been developed for the imitation of radiation–temperature parameters within Mars Climate Simulation Chamber (MCSC). In order to determine the values of annual and diurnal variations of the irradiance on the Martian surface, the Solar illumination E has been expressed by the distance r between the Sun and Mars and the Sun's altitude z in the Martian sky, along with its midday zenith distance zmin. The arrangements of spring and autumn equinoxes as well as summer and winter solstice points in the Martian sky are discussed regarding the perihelion of Mars. Annual orbital points and variability of Solar zmin for different planetary latitudes have been calculated for the 15 selected values of Mars's true anomaly, along with the illumination E for 12 hourly moments of Martian daytime on the Martian equator. These original calculations and the data which have been obtained are used for the construction of technical tools imitating variations of the surface irradiation and temperature within MCSC, programming of the supporting computer and the electric scheme, which provide proper remote control and set the environmental parameters that are analogues to the 24 hours 39 minutes circadian cycle on planet Mars. Spectral distribution as monochromatic irradiance, humidity control, atmospheric composition and other environmental parameters of planet Mars are also imitated and remotely controlled within MCSC, however, are not discussed in this particular article.
A system for illuminating a sample in situ with visible and ultraviolet light inside a transmission electron microscope was devised to study photocatalysts. There are many mechanical and optical factors that must be considered when designing and building such a system. Some of the restrictions posed by the electron microscope column are significant, and care must be taken not to degrade the microscope's electron-optical performance or to unduly restrict the other capabilities of the microscope. We discuss the nature of the design considerations, as well as the practical implementation and characterization of a solution. The system that has been added to an environmental transmission electron microscope includes a high brightness broadband light source with optical filters, a fiber to guide the light to the sample, and a mechanism for precisely aligning the fiber tip.
In this paper, the far-field pattern of a Cassegrain reflector is formulated. A novel illumination function is used to approximate the field distribution at the aperture of the reflector. The defined illumination function takes into account the central aperture blockage created by the subreflector. Using the illumination function, a closed-form expression describing the far-field radiation pattern of the Cassegrain reflector is formulated. The radiation pattern obtained from the derived equation is compared with the results obtained from physical optics and physical theory of diffraction. The results are found to be consistent with each other. It is found that the derived results show an impressive accuracy of 99.8% over the main-lobe region. The accuracy is found to be over 91 and 84% for the first and second significant side-lobe region, respectively, which can be considered satisfactory for many applications.
Variable phase dark-field contrast has been developed as an illumination technique in light microscopy, which promises significant improvements and a higher variability in imaging of several transparent specimens. In this method, a phase contrast image is optically superimposed on a dark-field image so that a partial image based on the principal zeroth-order maximum (phase contrast) interferes with an image that is based on the secondary maxima (dark field). The background brightness and character of the resulting image can be continuously modulated from a phase-contrast-dominated to a dark-field-dominated character. The condenser aperture diaphragm can be used for modulations of the image's appearance. Specimens can either be illuminated concentrically or obliquely (eccentrically) when parts of the illuminating light beams are covered and blocked. Moreover, a bright-field-like partial image can be added. In this way, the illumination can be optimally adjusted to the specific properties of the specimen. The techniques described can lead to improved visual information especially in biological specimens consisting of phase structures and additional light-absorbing or -reflecting components. Moreover, the specimen's three-dimensionality can be accentuated with improved clarity because the illuminating light beams associated with phase contrast and dark field run to the specimen at different angles of incidence.
The days of being able to ascertain instrument performance by simply peering through the eye pieces at a specimen are gone. However, users and granting agencies need to be confident that data collected on these instruments is uniform and quantifiable both over time and between instruments. Ideally, a LASER should not fluctuate, illumination should be completely uniform, and colors should be perfectly aligned. To check the current performance of imaging equipment, we conducted a worldwide research study utilizing three image-based tests: long-/short-term illumination stability, co-registration of signals across various wavelengths, and field illumination uniformity. To differentiate between “acceptable” and “unacceptable” performance, the deviation in illumination power could not exceed 10% (long term) or 3% (short term), the difference in the center-of-mass of imaged multicolored beads could not exceed >1 pixel between different wavelengths, and field illumination values could not exceed 10% (horizontal) or 20% (diagonal) deviation. This study established the current state of microscope performance through simple, efficient, and robust tests, while defining relative standards to assist cores in maintaining their instruments in optimal operating conditions. We developed cross-platform performance standards that will improve the validity of quantitative measurements made using various light microscopes.
Structured illumination fluorescence microscopy is a powerful super-resolution method that is capable of achieving a resolution below 100 nm. Each super-resolution image is computationally constructed from a set of differentially illuminated images. However, real-time application of structured illumination microscopy (SIM) has generally been limited due to the computational overhead needed to generate super-resolution images. Here, we have developed a real-time SIM system that incorporates graphic processing unit (GPU) based in-line parallel processing of raw/differentially illuminated images. By using GPU processing, the system has achieved a 90-fold increase in processing speed compared to performing equivalent operations on a multiprocessor computer—the total throughput of the system is limited by data acquisition speed, but not by image processing. Overall, more than 350 raw images (16-bit depth, 512 × 512 pixels) can be processed per second, resulting in a maximum frame rate of 39 super-resolution images per second. This ultrafast processing capability is used to provide immediate feedback of super-resolution images for real-time display. These developments are increasing the potential for sophisticated super-resolution imaging applications.
Organic light-emitting diodes (OLEDs) are developing into a competitive
alternative to conventional light sources. Nevertheless, OLEDs need further
improvement in terms of efficiency and color rendering for lighting
applications. Fluorescent blue emitters allow deep blue emission and high
stability, while phosphorescent blue emitter still suffer from insufficient
stability. The concept of triplet harvesting is the key for achieving
internal quantum efficiencies up to 100 % and simultaneously benefiting from
the advantages of fluorescent blue emitters. Here, we present a stacked OLED
consisting of two units comprising four different emitters in total. The
first unit takes advantage of the concept of triplet harvesting and combines
the light emission of a fluorescent blue and a phosphorescent red emitter.
The second unit emits light from a single emission layer consisting of a
matrix doped with phosphorescent green and yellow emitters. With this
approach, we reach white color coordinates close to the standard illuminant
A and a color rendering index of above 75. The presented devices are
characterized by high luminous efficacies of above 30 lm/W on standard glass
substrates without outcoupling enhancement.
For the transmission electron aberration-corrected microscope (TEAM) initiative of five U.S. Department of Energy laboratories in the United States, a correction system for the simultaneous compensation of the primary axial aberrations, the spherical aberration Cs, and the chromatic aberration Cc has been developed and successfully installed. The performance of the resulting Cc /Cs-corrected TEAM instrument has been investigated thoroughly. A significant improvement of the linear contrast transfer can be demonstrated. The information about the instrument one obtains using Young's fringe method is compared for uncorrected, Cs-corrected, and Cc /Cs-corrected instruments. The experimental results agree well with simulations. The conclusions might be useful to others in understanding the process of image formation in a Cc /Cs-corrected transmission electron microscope.