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Purpose: To evaluate the effect of the intracameral adrenaline and trypan blue used during cataract surgery on corneal endothelial parameters in pseudoexfoliation syndrome (PEX) patients. Methods: The patients were divided into four groups according to intraoperative use of agents during cataract surgery: intracameral adrenaline (1/10,000, 0.1 ml) (group 1), trypan blue (0.6 mg/ml, 0.1 ml) (group 2), combination of adrenaline and trypan blue (group 3) and none (group 4). Results: Preoperative ECD, CV, HEX and CCT parameters were similar between the groups. A mean loss of 12.7% in ECD was observed at the postoperative third months compared to the preoperative. In group 3, ECD was found to be lower in the postoperative third months compared to the preoperative (p = 0.014). In the other groups, no statistically significant difference was found in preoperative and postoperative comparisons. Conclusion: In conclusion, the utilization of intracameral adrenaline or trypan blue did not cause a significant difference in corneal endothelium in PEX patients. However, their combined use may have a negative effect on endothelial cell density. In a cataract surgery performed in the presence of PEX, the increased likelihood of endothelial damage should be taken into consideration, and appropriate precautions should be taken preoperatively and intraoperatively. [ABSTRACT FROM AUTHOR]

Estimating depth from images is a common technique in 3D perception. However, dealing with non-Lambertian materials, e.g., transparent or specular, is still nowadays an open challenge. However, to overcome this challenge with deep stereo matching networks or monocular depth estimation, data sets with non-Lambertian objects are mandatory. Currently, only few real-world data sets are available. This is due to the high effort and time-consuming process of generating these data sets with ground truth. Currently, transparent objects must be prepared, e.g., painted or powdered, or an opaque twin of the non-Lambertian object is needed. This makes data acquisition very time consuming and elaborate. We present a new measurement principle for how to generate a real data set of transparent and specular surfaces without object preparation techniques, which greatly reduces the effort and time required for data collection. For this purpose, we use a thermal 3D sensor as a reference system, which allows the 3D detection of transparent and reflective surfaces without object preparation. In addition, we publish the first-ever real stereo data set, called TranSpec3D, where ground truth disparities without object preparation were generated using this measurement principle. The data set contains 110 objects and consists of 148 scenes, each taken in different lighting environments, which increases the size of the data set and creates different reflections on the surface. We also show the advantages and disadvantages of our measurement principle and data set compared to the Booster data set (generated with object preparation), as well as the current limitations of our novel method. [ABSTRACT FROM AUTHOR]

Christine Montalbetti has published twenty-odd texts at the Éditions P.O.L over the years, beginning with Sa fable achevée, Simon sort dans la bruine, which appeared in 2001. While she has practiced short forms and theater (with several plays produced at the Comédie-Française), her central literary concern has been the novel. Her novels are innovative, engaging, and exceptionally canny constructions. Each of them testifies to a smart, sustained reflection on narrative art, upon its possibilities and its limits, upon its articulative power. Those novels are moreover "critical" in character. That is, they display a broad recognition of the tradition out of which they arise. They invite their reader to share that recognition, and to exercise his or her critical faculties in a very conscious manner. These are generous texts, granted the way in which Christine Montalbetti welcomes her reader into the fictional world, and encourages her or him to participate in a shared meditation on literature and its uses. Her books constitute one of the key sites where contemporary French literature takes full account of its potential and seeks new expressive avenues. [ABSTRACT FROM AUTHOR]

The goal of Mixed Reality (MR) is to achieve a seamless and realistic blending between real and virtual worlds. This requires the estimation of reflectance properties and lighting characteristics of the real scene. One of the main challenges within this task consists in recovering such properties using a single RGB-D camera. In this article, we introduce a novel framework to recover both the position and color of multiple light sources as well as the specular reflectance of real scene surfaces. This is achieved by detecting and incorporating information from both specular reflections and cast shadows. Our approach is capable of handling any textured surface and considers both static and dynamic light sources. Its effectiveness is demonstrated through a range of applications including visually-consistent mixed reality scenarios (e.g., correct real specularity removal, coherent shadows in terms of shape and intensity) and retexturing where the texture of the scene is altered whereas the incident lighting is preserved. [ABSTRACT FROM AUTHOR]

This article considers the relationships between brothers and sisters from the angle of a more primitive problematic which encompasses them. The archaic bond to the mother, with its moments of subject/object confusion and envious aggressiveness, pervades the ordinary rivalry proper to the fraternal bond - which is a corollary of the specular structure of the self, between narcissistic triumph and annihilation. An adult clinical case shows the traumatic depressant impact, in the transferential aftermath, of the birth of a younger brother - and how analysis was able to unravel this neurotic complex. [ABSTRACT FROM AUTHOR]

In scenes lit with sharp point-like light sources, light can bounce several times on specular materials before getting into our eyes, forming purely specular light paths. However, to our knowledge, rendering such multi-bounce pure specular paths has not been handled in previous work: while many light transport methods have been devised to sample various kinds of light paths, none of them are able to find multi-bounce pure specular light paths from a point light to a pinhole camera. In this paper, we present path cuts to efficiently render such light paths. We use a path space hierarchy combined with interval arithmetic bounds to prune non-contributing regions of path space, and to slice the path space into regions small enough to empirically contain at most one solution. Next, we use an automatic differentiation tool and a Newton-based solver to find an admissible specular path within a given path space region. We demonstrate results on several complex specular configurations, including RR, TT, TRT and TTTT paths. [ABSTRACT FROM AUTHOR]

In this work, we propose an overcomplete representation of multiview imagery for the purpose of compression. We present a rate-distortion (R-D) driven approach to decompose multiview datasets into two additive parts which can be interpreted as diffuse and specular content. We choose distinct and different sparsifying transforms for the diffuse and specular components and employ an R-D inspired measure as our optimization cost function to drive the decomposition based solely on compressibility. We first describe a framework which performs data separation in a registered domain to avoid the complexity of warping between views. Then a more comprehensive approach is proposed to separate specular data progressively from coordinates of multiple reference views. Experimental results show a coding gain of up to 0.6 dB for synthetic datasets and up to 0.9 dB for real datasets. [ABSTRACT FROM AUTHOR]

Fuchs endothelial corneal dystrophy (FECD) is characterized by the progressive degeneration of the corneal endothelium (CE). The purpose of this article is to review the diagnostic tools available to image and assess the CE in FECD. Slit-lamp biomicroscopy with specular reflection and retroillumination are important techniques to assess the CE. Objective diagnostic tests, such as retroillumination photographic analysis, specular microscopy, in vivo confocal microscopy (IVCM), and anterior segment optical coherence tomography, are valuable tools to evaluate the CE in FECD. Specular microscopy can be performed rapidly without touching the eye but requires a clear cornea with a smooth CE. In contrast, IVCM can image all layers of the cornea, even in advanced FECD. However, IVCM is contact-based and more technically challenging. It is important to select the appropriate objective diagnostic test to image and assess the CE in managing patients with FECD. [ABSTRACT FROM AUTHOR]

SCoBi-Veg stands for Signals of opportunity Coherent Bistatic scattering model for Vegetated terrains. It simulates polarimetric reflectometry of vegetation canopy over a flat ground using a Monte Carlo scheme. The model is aimed at assessing the value of navigation and communication satellite Signals of Opportunity in a range of frequencies from P- to S-bands for remote sensing of a number of geophysical land parameters such as soil moisture and biomass. A fully polarimetric expression for bistatic scattering from a vegetation canopy is first formulated for a general case and is then specialized to the practical case of ground-based/low-altitude platforms with passive receivers overlooking vegetation using the signals transmitted from large distances. Using analytical wave theory in conjunction with distorted Born approximation, the transmit and receive antenna effects (i.e., polarization crosstalk/mismatch, orientation, and altitude) are explicitly accounted for. The forward model developed here enables the understanding of the effect of different geophysical parameters and system configurations on the coherent and incoherent components of the reflected signatures. It can thus help developing robust inverse algorithm for extraction of soil moisture and biomass. The model is applied to P-band signals of geostationary communication satellites to describe polarimetric reflections from tree canopies as observed from down-looking platforms at various altitudes. The relative contributions of diffuse and specular scattering on total reflected power and reflectivity are quantified for various observing scenarios. [ABSTRACT FROM AUTHOR]

Summary: In this "hundreds" written in honor of Kathleen Stewart, I offer a dialectical image of subjects transfixed in the window of a New York City butcher shop, set against the backdrop of pandemic. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a solution to the problem of specular meteor radar interferometry cast on the complex plane. This technique is applicable to all meteor radars at the output of the receiver's pulsed Doppler signal processing chain. Specular meteor trail radar echoes are modeled as exponentially decaying sinusoids impinging on a sparse interferometric antenna array. A set of 10 underdense meteor trail radar parameters are estimated using nonlinear least squares optimization of the physical model parameters. Meteor trail spatial locations are determined by estimating all parameters through global optimization of the complex‐valued interferometric angle‐of‐arrival equations. Statistical precision of the estimated meteor radar parameters of Doppler, diffusion coefficient, angle‐of‐arrival, and height are subsequently characterized by calculation of the full covariance matrix. The determination of statistical uncertainties in the measured parameters is a key innovation in the field, as it lays the groundwork for calculating the statistical precision of the subsequently derived wind field. [ABSTRACT FROM AUTHOR]

Crosstalk effects in multilayer graphene nanoribbon (GNR) interconnects for the future nanoscale integrated circuits are investigated with the help of ABCD parameter matrix approach for intermediate- and global-level interconnects at 11nm and 8nm technology nodes. The worst-case crosstalk-induced delay and peak crosstalk noise voltages are derived for both neutral and doped zigzag GNR interconnects and compared to those of conventional copper interconnects. The worst-case crosstalk delays for perfectly specular, doped multilayer GNR interconnects are less than 4% of that of copper interconnects for 1mm long intermediate interconnects and less than 7% of that of copper interconnects for 5mm long global interconnects at 8nm node. As far as the worst-case peak crosstalk noise voltage is concerned, neutral GNR interconnects are slightly better performing than their doped counterparts. But from the perspective of overall noise contribution, doped GNR interconnects outperform neutral ones for all the cases. Finally, our analysis shows that from the signal integrity perspective, perfectly specular, doped multilayer zigzag GNR interconnects are a suitable alternative to copper interconnects for the future-generation integrated circuit technology. [ABSTRACT FROM AUTHOR]

We present a novel approach to real-time dense visual simultaneous localisation and mapping. Our system is capable of capturing comprehensive dense globally consistent surfel-based maps of room scale environments and beyond explored using an RGB-D camera in an incremental online fashion, without pose graph optimization or any post-processing steps. This is accomplished by using dense frame-to-model camera tracking and windowed surfel-based fusion coupled with frequent model refinement through non-rigid surface deformations. Our approach applies local model-to-model surface loop closure optimizations as often as possible to stay close to the mode of the map distribution, while utilizing global loop closure to recover from arbitrary drift and maintain global consistency. In the spirit of improving map quality as well as tracking accuracy and robustness, we furthermore explore a novel approach to real-time discrete light source detection. This technique is capable of detecting numerous light sources in indoor environments in real-time as a user handheld camera explores the scene. Absolutely no prior information about the scene or number of light sources is required. By making a small set of simple assumptions about the appearance properties of the scene our method can incrementally estimate both the quantity and location of multiple light sources in the environment in an online fashion. Our results demonstrate that our technique functions well in many different environments and lighting configurations. We show that this enables (a) more realistic augmented reality rendering; (b) a richer understanding of the scene beyond pure geometry and; (c) more accurate and robust photometric tracking. [ABSTRACT FROM AUTHOR]

Reality is the most realistic representation. We introduce a material display called ZoeMatrope that can reproduce a variety of materials with high resolution, dynamic range and light field reproducibility by using compositing and animation principles used in a zoetrope and a thaumatrope. With ZoeMatrope, the quality of the material is equivalent to that of real objects and the range of expressible materials is diversified by overlaying a set of base materials in a linear combination. ZoeMatrope is also able to express spatially-varying materials, and even augmented materials such as materials with an alpha channel. In this paper, we propose a method for selecting the optimal material set and determining the weights of the linear combination to reproduce a wide range of target materials properly. We also demonstrate the effectiveness of this approach with the developed system and show the results for various materials. [ABSTRACT FROM AUTHOR]

We considered whether optic flow generated by 3D relief of a foreground surface might influence visually-mediated self-motion perception (vection). We generated background motion consistent with self-rotation, and a foreground object with bumpy relief was either rotated with the observer (ego-centric) or fixed in world coordinates (world-centric).We found that vection strength ratings were greater in conditions with world-centric retinal motion of the foreground object, despite generating flow that was opposite to background motion. This effect was explained by observer judgments of the axis self-rotation in depth; whereas ego-centric flow generated experiences of more on-axis self-rotation, world-centric flow generated experiences of centrifugal rotation around the foreground object. These data suggest that foreground object motion can increase the perception of self-motion generated by optic flow, even when they reduce net retinal motion coherence and promote conditions for multisensory conflict. This finding supports the view that self-motion perception depends on mid-level representations of whole-scene motion. [ABSTRACT FROM AUTHOR]

The objective of the work is to model the shape of the sinusoidal shape of regular water waves generated in a laboratory flume. The waves are traveling in time and render a smooth surface, with no white caps or foam. Two methods are proposed, treating the water as a diffuse and specular surface, respectively. In either case, the water is presumed to take the shape of a traveling sine wave, reducing the task of the 3D reconstruction to resolve the wave parameters. The first conceived method performs the modeling part purely in 3D space. Having triangulated the points in a separate phase via bundle adjustment, a sine wave is fitted into the data in a least squares manner. The second method presents a more complete approach for the entire calculation workflow beginning in the image space. The water is perceived as a specular surface, and the traveling specularities are the only observations visible to the cameras, observations that are notably single image. The depth ambiguity is removed given additional constraints encoded within the law of reflection and the modeled parametric surface. The observation and constraint equations compose a single system of equations that is solved with the method of least squares adjustment. The devised approaches are validated against the data coming from a capacitive level sensor and on physical targets floating on the surface. The outcomes agree to a high degree. [ABSTRACT FROM AUTHOR]

The multifrequency biplanar interferometric imaging technique (MBI) is applied to data from vertical, split-beam echosounders to produce sub-beam estimates of seabed surface-backscattering strength (Ss), incidence angle (θ), and roughness (${\rm {\cal R}}$). A simple model is used to quantify the variation of Ss versus θ = {2–20°} and acoustic frequency, f = {18, 38, 70, 120 and 200 kHz}. The coefficients of the angle- and frequency-dependent terms of the model indicate seabed material properties, principally small- and large-scale roughness and hardness. These indices are combined with the estimates of θ and ${\rm {\cal R}}$ to classify the seabed using unsupervised cluster analysis. This technique is applied to data from the Forty-Three-Fathom Bank, a seamount in the Southern California Bight. The resulting seabed classifications are consistent with the surficial lithology and the spatial distribution of known rockfish (Sebastes spp.) habitat. The method should be generally applicable to seabed classification. [ABSTRACT FROM PUBLISHER]

In many industrial applications, it is important to identify defects on specular surfaces. On machined surfaces, defect identification may be further complicated by the presence of marks from a machining process. These marks may dramatically and unpredictably change the appearance of the surface, while not altering its ability to function. To differentiate between surface characteristics that constitute a defect and those that do not, we propose a system that directly illuminates specular machined surfaces with a programmable array of high-power light-emitting diodes that allows the angle of the incident light to be varied over a series of images. A reflection model is used to predict the reflected intensity as a function of incident lighting angle for each point on the imaged surface. A surface defect causes the observed reflected intensity as a function of incident lighting angle to differ from that predicted by the reflection model. Such differences between the observations and the reflection model are shown to identify surface defects such as porosities, dents and scratches in the presence of marks from the machining process. [ABSTRACT FROM AUTHOR]

Certain characteristics of a material such as the surface reflectivities can be determined even without knowledge of its internal properties. In this letter, a direct relationship (Azzam relationship) and an analytical approximation (Azzam–Sohn–Hong (ASH) approximation) between the vertically and horizontally polarized reflectivities of specular surfaces are derived and validated using the refractive indices of water and metal in a variety of spectral regions. For the purpose of practical remote applications, land, sea water, sea ice, and oil surfaces are considered and compared using the Hong and ASH approximations. Consequently, ASH approximation has an advantage in a variety of spectral bands for materials with a small imaginary part of refractive index, while the Hong approximation does well in the microwave spectral region, or when the imaginary part of the reflective index is not neglected. Thus, a combination of the Hong and ASH approximations is suggested to improve upon previous studies that used only the Hong approximation in a variety of applications. [ABSTRACT FROM PUBLISHER]

It is well known that ambient light reduces the contrast ratio. However binocular human perception is often better than expected by monocular measurements. We evaluated this by subjects and adapted the measurement set-up to binocular vision. Typical mobile displays were examined and we verified the binocular visual perception of small specular light sources. [ABSTRACT FROM AUTHOR]

This state of the art report covers reconstruction methods for transparent and specular objects or phenomena. While the 3D acquisition of opaque surfaces with Lambertian reflectance is a well-studied problem, transparent, refractive, specular and potentially dynamic scenes pose challenging problems for acquisition systems. This report reviews and categorizes the literature in this field. Despite tremendous interest in object digitization, the acquisition of digital models of transparent or specular objects is far from being a solved problem. On the other hand, real-world data is in high demand for applications such as object modelling, preservation of historic artefacts and as input to data-driven modelling techniques. With this report we aim at providing a reference for and an introduction to the field of transparent and specular object reconstruction. We describe acquisition approaches for different classes of objects. Transparent objects/phenomena that do not change the straight ray geometry can be found foremost in natural phenomena. Refraction effects are usually small and can be considered negligible for these objects. Phenomena as diverse as fire, smoke, and interstellar nebulae can be modelled using a straight ray model of image formation. Refractive and specular surfaces on the other hand change the straight rays into usually piecewise linear ray paths, adding additional complexity to the reconstruction problem. Translucent objects exhibit significant sub-surface scattering effects rendering traditional acquisition approaches unstable. Different classes of techniques have been developed to deal with these problems and good reconstruction results can be achieved with current state-of-the-art techniques. However, the approaches are still specialized and targeted at very specific object classes. We classify the existing literature and hope to provide an entry point to this exiting field. [ABSTRACT FROM AUTHOR]

There is an expansion of celebrity culture outward. Through new media forms, greater portions of the populace are now constucting online public personas. The best way to understand this proliferation of the public presentation of the self is through the term specular, a two-way mirror of projection on to the screen and the circulation of and interaction with those images and texts into the wider world. What is now well-developed is a specular economy whose foundations are derived from the much longer tradition of celebrity culture and whose repercussions relate to an emerging comfortability with a society of surveillance. [ABSTRACT FROM AUTHOR]

This work is in direct line with the Concordiasi international project. It aims to better constrain atmospheric analyses by improving the assimilation of low-level Advanced Microwave Sounding Unit (AMSU)-A and AMSU-B microwave observations over Antarctica. So far, a very small amount of available AMSU observations is effectively assimilated over Antarctica. To assimilate more observations, different issues have to be dealt with. In this work, the surface emissivity issue over Antarctica is examined. In a first step, a thorough review of the use of a specular assumption to calculate emissivity from AMSU-A measurements has been undertaken. The effect of five different assumptions about the surface on retrieved AMSU emissivities has then been evaluated using a one-year database: specular, Lambertian, and three intermediate assumptions. Simulations of brightness temperatures at AMSU sounding frequencies have been produced using a radiative transfer model. The emissivities obtained using the five assumptions have been found very useful in improving these simulations. The most successful schemes are found to be the Lambertian scheme during the winter season and a specular or an intermediate scheme (50% specular, 50% Lambertian) during Antarctica's short summer. [ABSTRACT FROM AUTHOR]

A polarized neutron reflectometer for vertical samples is available at Dhruva reactor guide hall, Trombay. The reflectometer has been designed for horizontal scattering vector. It uses a position-sensitive detector for obtaining the reflectivity pattern. This arrangement allows one to obtain diffuse or off-specular intensity around any specular peak at one go. We have used this instrument for studying the structure of various metal{ metal and metal{semiconductor multilayers by specular reflectometry. We have also been successful in understanding interface morphology of several films through diffuse neutron reflectometry (DNR) on this reflectometer. Some of the recent results are presented in this paper to demonstrate the strength of these two techniques. [ABSTRACT FROM AUTHOR]

A polarized neutron reflectometer for vertical sample geometry has been installed in the guide tube laboratory of Dhruva reactor at Trombay, India. The instrument uses a monochromatic neutron beam of 2.5 Å in a step scan mode with a linear position sensitive detector for data collection. This allows one to collect off-specular or diffuse neutron reflectivity (DNR) data quite easily besides specular reflectivity data. The design aspects of this instrument have been presented. The instrument can easily switch between unpolarized and polarized mode, since the beam to the sample is prepared by reflection from a polarizing supermirror or a non-polarizing supermirror. Specular reflectivity studies in unpolarized and polarized mode, for chemical and magnetic structure of thin film samples have been presented. DNR data has been collected from a Ni film. Interface morphology at the air-film interface has been obtained from this data. [ABSTRACT FROM AUTHOR]

Terrestrial brightness temperatures measured from satellites have been used to determine the surface emissivity. The results not only depend on surface temperature and on atmospheric properties, but also on the type of surface scattering. For otherwise identical conditions (same emissivity, same nonscattering atmosphere), the radiation above the Lambertian surface is larger than for a specular surface if the incidence angle is smaller than about 55°. The opposite is true for larger angles. The effect leads to overestimates of emissivity for observations especially near nadir with the use of algorithms assuming specular reflection. The problem may be solved by the introduction of a specularity parameter to characterize realistic surfaces by a combination of specular and Lambert scattering. A simple solution lies in the use of conically scanning radiometers at a constant incidence angle near 55°. Although the topic applies to all ranges of thermal radiation, the present discussion concentrates on the microwave spectrum in the Rayleigh-Jeans approximation. [ABSTRACT FROM PUBLISHER]

The purpose of this work is to study the effects of specularly reflecting wall under the combined radiative and laminar free convective heat transfer in an infinite square duct. An absorbing and emitting gray medium is enclosed by the opaque and diffusely emitting walls. The walls may reflect diffusely or specularly. Boussinesq approximation is used for the buoyancy term. The radiative heat transfer is evaluated using the direct discrete ordinates method. The parameters under considerations are Rayleigh number, conduction to radiation parameter, optical thickness, wall emissivity and reflection mode. The differences caused by the reflection mode on the stream line, and temperature distribution and wall heat fluxes are studied. Some differences are observed for the categories mentioned above if the order of the conduction to radiation parameter is less than order of 10-3 for the range of Rayleigh number studied. The differences at the side wall heat flux distributions are observed as long as the medium is optically thin. As the top wall emissivity decreases, the differences between these two modes are increased. As the optical thickness decreases at the fixed wall emissivity, the differences also increase. The difference of the streamlines or the temperature contours is not as distinct as the side wall heat flux distributions. The specular reflection may alter the fluid motion. [ABSTRACT FROM AUTHOR]

With the recent increase in numbers of small and versatile low-power meteor radars, the opportunity exists to benefit from simultaneous application of multiple systems spaced by only a few hundred km and less. Transmissions from one site can be recorded at adjacent receiving sites using various degrees of forward scatter, potentially allowing atmospheric conditions in the mesopause regions between stations to be diagnosed. This can allow a better spatial overview of the atmospheric conditions at any time. Such studies have been carried out using a small version of such so-called multistatic meteor radars, e.g. Chau et al. (Radio Sci 52:811-828, 2017, 10.1002/2016rs006225). These authors were able to also make measurements of vorticity and divergence. However, measurement uncertainties arise which need to be considered in any application of such techniques. Some errors are so severe that they prohibit useful application of the technique in certain locations, particularly for zones at the midpoints of the radars sites. In this paper, software is developed to allow these errors to be determined, and examples of typical errors involved are discussed. The software should be of value to others who wish to optimize their own MMR systems. [ABSTRACT FROM AUTHOR]