Subtle Color Research Articles

Global spectrophotometric properties of Asteroid (21) Lutetia using Rosetta-OSIRIS images

We present a spectrophotometric analysis of the surface areas of asteroid (21) Lutetia that were imaged during the Rosetta flyby on July 2010 by the OSIRIS camera in the wavelength range 269 to 989 nm. A spectral slope change with respect to phase angle is found and interpreted as being due to areal diversity of Lutetia's surface. We applied Minnaert and Hapke models to disk-integrated and disk-resolved data of Lutetia. Except for the albedo in both models, the Minnaert (limb darkening k) and Hapke (roughness) parameter display no dependence on wavelength. The single scattering albedo, ω, shows a relative flat spectrum across the wavelength range with a slope of (1.65±0.29)% per 100 nm. The Hapke roughness parameter of Lutetia is constrained to be 28°± 1° in average for all wavelengths. We generated three different color ratio maps to investigate the overall color variation across the surface of Lutetia. Apart from differences on local scale no significant color variations are found across the regions imaged on Lutetia's surface (Achaia, Noricum, Narbonensis, Baetica and Etruria). Based on (931.9-nm/269.3-nm) color ratio map, the typical color contrast is estimated to be on the order of 10%. We note that, compared to other asteroids visited by spacecraft, the subtle color variation in order of 10% or less is observed for E-type asteroid (2867) Steins and the C-type asteroid (253) Mathilde.

Икона Ветхозаветной Троицы с деяниями из Успенского собора Тихвинского монастыря: проблемы датировки и интерпретации

The origins of the illustrated cycles of the “wanderings” of the Holy Trinity are usually connected with the mid-16th century, a time when after the Moscow Kremlin Fire (1547) new icons for the royal Annunciation Church were commissioned from the Pskov and Novgorod masters. The border scenes of the new icon of the Old Testament Trinity became one of the central themes of the Case of Diak Viskovaty and the conciliar sessions which followed (1553–1554). The “Doubts and Outrage” of I. Viskovaty were causedby the newly-painted image of Christ, depicted as an Angel, with the octagonal halo of Saint Sophia, the Wisdom of God (seen by some theologians as the ultimate depiction of the Second Hypostasis of the Trinity before the Incarnation). Viskovaty saw a fundamental flaw and temptation in such depictions, since they might have presumed that the Lord took up not only the human nature, but also the angelic. The original icon from Kremlin did not survive, but it is widely believed that its iconographic composition was replicated in all depictions of the Holy Trinity with Acts, painted in the middle and second half of the 16th century. One of these (as traditionally upheld in the academic world) was the icon from Tikhvin, now in collection of theState Tretiakov Gallery, which is surrounded by 24 border scenes that illustrate not only the Book of Genesis and the “wanderings” of the Angels, but also the Life of the Theotokos, Gospel scenes and the Akathistos. Yet it is worth noting that the unique iconographic composition of the given piece, the striking traits of itsstyle and artistry give us every reason not only to attribute the icon to Pskov masters, but also to consider it the oldest among such images. The iconographer clearly retains the volume and proportional balance of thefigures, the softness of the facial depictions, the color work, the generous use of the gold hatching. All of these elements allow us to consider this icon a work of art from the dawn or first quarter of the 16th century. The icon in question follows the same tradition in Pskov art that brought us the Fiery Ascension of the Prophet Elijah (State Museum of History) and the Old Testament Trinity (State Tretiakov Gallery), but stands apart in its subtle color pallet and lack of ornamentation. The centerpiece of the icon, as well as the border scene of “Acts” follow the unique iconographic variations, known only in Pskov. The original interpretation of these themes can easily be justified, since the dedication of the Cathedral to the Holy Trinity is clearly linked with the prolonged evolution of the Trinitarian iconography. All of the border scenes can be split into two thematic categories. The major part (border scenes 1–14) is dedicated to the Book of Genesis. The lesser — to the Gospel narrative and Akathistos hymns. There is reason to believe that this unusual combination of border scene themes, surrounding the Holy Trinity, originated exclusively in Pskov in the late 15th century. The outermost border scenes in the lower tier — depicting Saint Sophia (the Wisdom of God) and the Dormition — coincide directly with the dedication of the Dormition Cathedral in the Tikhvin Monastery, which was part of the Diocese of Novgorod. Since the icon originates from that exact monastery, one should believe that it was painted for the consecration of the Cathedral in 1515.

Production and Polyphenolic Composition of Tea

Tea (Camellia sinensis) is the second most commonly consumed beverage in the world, and its consumption has been associated with several important health benefits due in part to its high concentration of polyphenolic compounds. Tea varieties, including white, green, oolong, pu-erh, and black tea, are all produced from the same plant but differ in postharvest processing. The level of oxidative processing from white to black tea (low to high) drives changes in polyphenol profiles from monomeric polyphenols (catechins) to oxidative products (theaflavins and thearubigins) that convert the subtle yellow color of green tea to the distinctive red/copper color of oolong and black tea. Polyphenol compounds from green teas have been well studied; however, oxidative products are more difficult to characterize and may require a combination of analytical techniques for identification and quantification. This technical summary introduces the major polyphenols in tea and discusses the main steps of tea processing and instrumentation used for polyphenol analysis.

Chemical Sensing in Real Time with Plants Using a Webcam.

It has been established that plants can smell and respond to chemicals in order to adapt to and survive in a changing chemical environment. Here we show that a plant responds to chemicals in air, and the response can be detected rapidly to allow tracking of air pollution in real time. We demonstrate this capability by detecting subtle color and shape changes in the leaves of mosses upon exposure to sulfur dioxide in air with a simple webcam and an imaging-processing algorithm. The leaves of mosses consist of a monolayer of cells, providing a large surface-to-volume ratio for highly sensitive chemical sensing. The plant sensor responds linearly to sulfur dioxide within a wide concentration range (0-180 ppm), and it can tolerate humidity variation (15-85% relative humidity) and chemical interference and regenerate itself. We envision that plants can help alert chemical exposure danger as a part of our living environment using low-cost CMOS imagers, and their chemical-sensing capabilities may be further improved with genetic engineering.

A Comparative Survey of Methods for Remote Heart Rate Detection From Frontal Face Videos.

Remotely measuring physiological activity can provide substantial benefits for both the medical and the affective computing applications. Recent research has proposed different methodologies for the unobtrusive detection of heart rate (HR) using human face recordings. These methods are based on subtle color changes or motions of the face due to cardiovascular activities, which are invisible to human eyes but can be captured by digital cameras. Several approaches have been proposed such as signal processing and machine learning. However, these methods are compared with different datasets, and there is consequently no consensus on method performance. In this article, we describe and evaluate several methods defined in literature, from 2008 until present day, for the remote detection of HR using human face recordings. The general HR processing pipeline is divided into three stages: face video processing, face blood volume pulse (BVP) signal extraction, and HR computation. Approaches presented in the paper are classified and grouped according to each stage. At each stage, algorithms are analyzed and compared based on their performance using the public database MAHNOB-HCI. Results found in this article are limited on MAHNOB-HCI dataset. Results show that extracted face skin area contains more BVP information. Blind source separation and peak detection methods are more robust with head motions for estimating HR.

Watercolor Woodblock Printing with Image Analysis

AbstractWatercolor paintings have a unique look that mixes subtle color gradients and sophisticated diffusion patterns. This makes them immediately recognizable and gives them a unique appeal. Creating such paintings requires advanced skills that are beyond the reach of most people. Even for trained artists, producing several copies of a painting is a tedious task. One can resort to scanning an existing painting and printing replicas, but these are all identical and have lost an essential characteristic of a painting, its uniqueness. We address these two issues with a technique to fabricate woodblocks that we later use to create watercolor prints. The woodblocks can be reused to produce multiple copies but each print is unique due to the physical process that we introduce. We also design an image processing pipeline that helps users to create the woodblocks and describe a protocol that produces prints by carefully controlling the interplay between the paper, ink pigments, and water so that the final piece depicts the desired scene while exhibiting the distinctive features of watercolor. Our technique enables anyone with the resources to produce watercolor prints.

Two new species of the Ophisops microlepis (Squamata: Lacertidae) complex from northwestern India with a key to Indian Ophisops

ABSTRACTWe describe two new species of the lacertid genus Ophisops based on a series of 19 specimens from semi-arid habitats in the states of Gujarat and Rajasthan in northwestern India, provide a description of Ophisops microlepis sensu stricto, and a key to Indian Ophisops. Ophisops pushkarensis sp. nov. and Ophisops kutchensis sp. nov. are allied to Ophisops microlepis and can be diagnosed from all other Indian Ophisops by the fusion of the lower and upper eyelids, their large body size (snout to vent length > 50 mm), and ≥ 50 scales around midbody. They differ from O. microlepis and each other in the number of scales around midbody, the number of dorsal scales, subtle colour pattern differences, as well as uncorrected mitochondrial sequence divergence (6–9%). These are some of the only known endemic reptiles in these semi-arid landscapes and indicate that many other such habitats may harbour endemic biodiversity.www.zoobank.org/urn:lsid:zoobank.org:pub:3CD04F6F-D699-4100-A462-9BDD4B36FEE2

The exquisitely painful fingertip – subungual glomus tumours

While most painful fingertips have a distinct causal history and/or associated symptoms, some can leave the practitioner at a loss during diagnosis. We present a rare differential that often has an indistinct history, subtle clinical signs and is commonly misdiagnosed, with average diagnosis time reported as 7 years 1. A 25-year-old patient presented with a several-year history of a gradually increasingly painful fingertip, just beneath her nail plate. There was no history of trauma or precipitating event she could recollect. She had been assessed by several practitioners over the years with normal radiology and ineffective neuromodulation, and analgesics offered little effect. On examination, she had a minimal area of slight blue discolouration under her nail plate, which elicited exquisite pain on palpation. This was diagnosed clinically as a subungual glomus tumour based on the symptom of exquisite pain in the fingertip without causal history and the subtle colour discolouration. Treatment was surgical excision under a digital nerve block with removal of the overlying nail plate. The lesion was characterised as a spot directly beneath the nail plate (Figure 1A), with a leash of proximal feeding vessels (Figure 1B). Excision was performed and the resulting defect closed directly (Figure 1C). Histology subsequently confirmed the clinical diagnosis of a glomus tumour, and on postoperative review, she was pain free. Glomus tumours were first described by Wood in 1812, with subsequent histological characterisation by Masson in 1924 2, 3. They are rare, typically benign tumours that arise from the neuromyoarterial structure of the glomus body, a structure believed to serve a thermoregulatory purpose 4. They account for 1–4·5% of hand tumours and are more common in women 1, 5. Although within the hand, the most common site being subungual, glomus tumours may also be found under the nail fold, nail matrix and within the pulp. They characteristically present with a triad of a tender, single, identifiable spot, which is hypersensitive to the cold and causes extreme pain 2. Two clinical tests, with high specificity, are commonly used to aid diagnosis: Love and Heldrith's tests. “Love's test” describes using a small rounded tip, such as a ball point pen nib, to press against the lesion eliciting exquisite pain. “Heldrith's test” involves raising the arm above heart level to exsanguinate the limb prior to inflation of a blood pressure cuff over the upper arm. The patient may experience symptomatic relief during this phase. The pressure cuff is then released, and pain is instantly elicited in the fingertip with a positive test 1, 6. Magnetic resonance imaging and ultrasound scanning have been shown to play a role in delineating the extent and location of the tumour, although this is not clinically indicated 7. In summary, when presented with a patient who has an extremely painful fingertip and an unclear history, never forget the rare but debilitating glomus tumour and refer the patient on to a hand surgeon for further management.

Siltstones Across the Daptocephalus ( Dicynodon ) and Lystrosaurus Assemblage Zones, Karoo Basin, South Africa, Show No Evidence For Aridification

Abstract: Changes in the record of vertebrate-assemblage zones in the Karoo Basin, South Africa, serve as a model for the response of terrestrial ecosystems to the end-Permian biotic crisis. Vertebrate turnover from the Daptocephalus to Lystrosaurus Assemblage Zone is believed to have begun with the appearance of subtle siltstone-color variance and is coeval with a unique, laminated lithofacies, both of which are interpreted by other workers to represent evidence for an aridification trend. The laminated facies consists of interbedded greenish-gray and dark reddish-gray siltstone, with coloration of the latter reported as a function of an increasing eolian component. The current study combines stratigraphy, petrography, geochemistry, and rock magnetic properties of an interlaminated succession and lateral equivalents at Old Lootsberg Pass in the Eastern Cape Province to determine whether such subtle color variance is a function of aridification and, hence, climate change. Siltstones were evaluated from intervals both below and above a pedogenic nodule-bearing feldspathic wacke that is physically correlated over a > 0.5 km distance. The lower succession consists of interbedded greenish-gray ( sensu latu ) and reddish-gray ( sensu latu ) siltstone in which undisturbed and minimally disturbed primary sedimentary, along with few secondary biogenic structures, are interpreted to represent deposition in an abandoned channel-fill complex. Massive greenish-gray and dark reddish-gray siltstone above the channel complex demonstrate that coloration is variable across laterally equivalent strata. Both lithologies were assessed using X-ray fluorescence, X-ray diffraction, Mossbauer spectroscopy, scanning electron microscopy with EDS, and bulk magnetic susceptibility, stepwise acquisition of an isothermal remanent magnetization (IRM), and backfield direct field demagnetization. Our data indicate that there is no statistically significant difference in major-element concentrations between lithologies and that subtle color difference is a function of the presence of fine ( Lystrosaurus Assemblage Zone was not arid. In contrast, the landscape was wet, that allowed for the continued growth of a Permian-age flora under conditions of high water table that experienced temporal fluxes in the hydrological regime promoting spatial color modification of sediment.

Human colour in mate choice and competition.

The colour of our skin and clothing affects how others perceive us and how we behave. Human skin colour varies conspicuously with genetic ancestry, but even subtle changes in skin colour due to diet, blood oxygenation and hormone levels influence social perceptions. In this review, we describe the theoretical and empirical frameworks in which human colour is researched. We explore how subtle skin colour differences relate to judgements of health and attractiveness. Also, because humans are one of the few organisms able to manipulate their apparent colour, we review how cosmetics and clothing are implicated in courtship and competition, both inside the laboratory and in the real world. Research on human colour is in its infancy compared with human psychophysics and colour research in non-human animals, and hence we present best-practice guidelines for methods and reporting, which we hope will improve the validity and reproducibility of studies on human coloration.This article is part of the themed issue 'Animal coloration: production, perception, function and application'.

For Art’s Sake: The Aesthetic Movement in Print & Beyond, 1870–1890: The Grolier Club of New YorkJanuary 25–March 11, 2017CatalogueFor Art’s Sake: The Aesthetic Movement in Print & Beyond, 1870–1890Eric HolzenbergNew York: The Grolier Club, 2017.136 pp.; 146 color ills.Paper over board $50ISBN 9781605830643

For Art’s Sake: The Aesthetic Movement in Print &amp; Beyond, 1870–1890: The Grolier Club of New YorkJanuary 25–March 11, 2017Catalogue<i>For Art’s Sake: The Aesthetic Movement in Print &amp; Beyond, 1870–1890</i>Eric HolzenbergNew York: The Grolier Club, 2017.136 pp.; 146 color ills.Paper over board $50ISBN 9781605830643

Type I cod haemoglobin no better than type II in warm water

Not all cod are created equal. Scratch beneath the surface and an essential difference in their blood appears. Michael Berenbrink from the University of Liverpool, UK, explains that most cod found at the southern extent of their range tend to produce a specific form (genotype) of the oxygen carrying protein haemoglobin in their red blood cells (type I haemoglobin), while individuals from the population further north tend to carry a second form of the protein (type II). And when fish with one or other of the two haemoglobin forms are offered a choice of temperatures, cod carrying the first prefer warmer conditions, while those carrying the second select the chillier water. ‘There is something that translates from the genotype to how the whole organism behaves in a thermal gradient, so there must be something that is different, but what it is we don't know’, says Berenbrink.Evidence suggested that the different haemoglobins could lie at the heart of the population distributions, if the first form of haemoglobin allowed the fish to transport more oxygen in warm conditions while the second haemoglobin was optimised for oxygen transport in cold conditions. ‘But nobody has ever checked this carefully’, says Berenbrink. With the possibility that climate change may eradicate cod from the Irish Sea by the end of this century, Berenbrink and his colleagues, Samantha Barlow, Julian Metcalfe and David Righton, decided to test how tightly red blood cells from fish in the Irish Sea bind oxygen.Knowing that she could catch type I and type II individuals in the Liverpool bay, Barlow headed out into the ferocious sea conditions in the dead of winter on charter boats to fish for blood samples. ‘We chose that time of year because there was no difference in the water column temperature and we took all of the fish from a certain spot’, says Berenbrink, explaining that different temperature experiences and stress can dramatically affect how tightly fish red blood cells bind oxygen. And when Barlow returned to the lab with the precious vials of blood, she had to work fast, running the red blood cell proteins on a gel to identify which form of haemoglobin each individual fish carried before selecting the blood group she would test the following day. She then cautiously isolated the red blood cells and stabilised them at three different temperatures (5, 12.5 and 20°C) and three different pHs (7.9, 7.65 and 7.4), before painstakingly adjusting the oxygen concentration in the red blood cells (ranging from 0–100% air) and measuring the subtle colour change as the haemoglobin in the red blood cells absorbed the gas, to determine how tightly the blood cells bound oxygen.However, when Barlow plotted the characteristic S-shaped oxygen binding curves and adjusted for the internal pH change that occurs naturally as blood cells warm, she and Berenbrink could see that all of the curves essentially overlapped. The different forms of the oxygen carrying haemoglobin did not affect the red blood cells’ ability to bind oxygen at different temperatures, despite the fish's temperature preferences: ‘We are back to the drawing board to figure out what limits cod thermal tolerance’, says Berenbrink.Realising that the red blood cell oxygen binding was essentially identical, the duo then pooled the data from all 16 samples and calculated how well the fish could absorb oxygen and deliver it to tissues as their temperature and metabolic rates increase under future climate scenarios. However, their calculations suggest that the fish's red blood cells will struggle to meet their increasing oxygen demands at temperatures around 20°C and above. ‘This does not necessarily mean the animal is doomed, just that any improvements in oxygen supply must come from other sources’, Berenbrink concludes.

Eulerian video magnification and analysis

The world is filled with important, but visually subtle signals. A person's pulse, the breathing of an infant, the sag and sway of a bridge---these all create visual patterns, which are too difficult to see with the naked eye. We present Eulerian Video Magnification, a computational technique for visualizing subtle color and motion variations in ordinary videos by making the variations larger. It is a microscope for small changes that are hard or impossible for us to see by ourselves. In addition, these small changes can be quantitatively analyzed and used to recover sounds from vibrations in distant objects, characterize material properties, and remotely measure a person's pulse.

Reflectance Transformation Imaging (RTI) of saw marks on bones

Abstract Reflectance Transformation Imaging (RTI) is a photographic method where a series of lighting details are captured to create an interactive digital image that, combined with associated software, enhances the surface details of an object. Primarily used in archaeological applications, RTI has been making a transition into forensic science. The ability to capture subtle color and surface variation details makes RTI potentially appealing for examining surface alterations such as tool impressions on bone. This study investigated whether RTI may be useful for preservation and analysis of saw marks on bones through a comparison of RTI photographs to traditional photographic counterparts. RTI was found to be excellent for visualizing tool mark on bones, though it was more successful in capturing shallow surface details versus deeper alterations. Time and file storage may be minor limitations, but overall RTI is relatively inexpensive, easy to perform, and effective for imaging alterations on bones.

The medial temporal lobe supports sensing-based visual working memory

It is well established that the medial temporal lobe (MTL), including the hippocampus, is essential for long-term memory. In addition, recent studies suggest that the MTL may also support visual working memory (VWM), but the conditions under which the MTL plays a critical role are not yet clear. To address this issue, we used a color change detection paradigm to examine the effects of MTL damage on VWM by analyzing the receiver operating characteristics of patients with MTL damage and healthy age- and education-matched controls. Compared to controls, patients with MTL damage demonstrated significant reductions in VWM accuracy. Importantly, the patients were not impaired at making accurate high-confidence judgments that a change had occurred; however, they were impaired when making low-confidence responses indicating that they sensed whether or not there had been a visual change. Moreover, these impairments were observed under conditions that emphasized the retrieval of complex bindings or the retrieval of high-resolution bindings. That is, patients with MTL damage exhibited VWM impairments when they were required to remember either a larger number of low-resolution bindings (i.e., set size of 5 and obvious color changes) or a smaller number of high-resolution bindings (i.e., set size of 3 and subtle color changes). The results indicate that only some VWM processes are dependent on the MTL, and are consistent with the proposal that the MTL plays a critical role in forming complex, high-resolution bindings.

Comparison of LED and Laser Forensic Light Source for Detection of Semen Stain

정액흔을 효과적으로 탐색하기 위하여 LED 기반 법광원 장비인 Polilight Flare plus 2(이하PF+2)와 Laser 기반 법광원 장비인 BrightBeam Laser ULTRA (이하 BBL Ultra)의 성능과 특성을 각각 비교하였다. PF+2는 주황색, BBL Ultra는 노란색 고글을 이용하였을 경우에 가장 선명한 정액흔을 발견할 수 있었으며 두 법광원의 탐색 최소한계는 큰 차이를 보이지 않았다. 특이성 연구결과, 소변, 커피 및 주스에서 비교적 약한 형광이 관찰되었고 질액, 혈액 및 타액에서는 형광이 관찰되지 않았으며 일부 시료들 간의 미세한 형광색상 및 밝기 차이를 구분하는데 BBL Ultra가 PF+2보다 효과적이었다. 색상의 종이에 부착된 정액흔 시험결과로부터 빨간색과 분홍색에서 PF+2로는 보이지 않았던 정액흔이 BBL Ultra를 사용하였을 때 관찰되었다. 그러므로 범죄현장 증거물로부터 다양한 정액흔을 탐색하는데 BBL Ultra가 PF+2보다 더욱 효과적인 것으로 판단되었다.In this study, we compared two Forensic Light Sources (FLSs), LED-based Polilight Flare plus 2 (PF+2) and Laser-based BrightBeam Laser ULTRA (BBL Ultra), in order to detect semen stain from crime scene evidences. The best combinations of FLSs and goggles for detecting semen stain were PF+2/orange and BBL Ultra/yellow, respectively. There were no significant difference in sensitivity for both FLSs. In specificity study, urine, coffee, and juice showed relatively low intensity of fluorescence by both FLSs, however no fluorescence were detected for vaginal fluid, whole blood, and saliva. We found that BBL Ultra is superior to distinguish subtle color and brightness difference between several samples. From the results of background effect tests using semen stain on colored paper, it was shown that PF+2 could not detect the semen stain on the red and pink paper, but BBL Ultra could detect the semen stain. Therefore, we suggested that BBL Ultra was suitable forensic light source for detection of semen stains.

Surgical anatomy and physiology of swallowing

Deglutition, the act of swallowing, is an extremely complex process involving approximately 50 pairs of muscles and nerves that are responsible for preparing and transferring food and liquids from the mouth to the stomach. A problem with any of these structures can lead to dysphagia and a decrease in the quality of life in patients suffering from it. To successfully diagnose and treat dysphagia, a thorough understanding of deglutition is essential. The anatomy and physiology of the swallowing process is reviewed as it pertains to operative approach and technique.

Integrated organic geochemistry with palynofacies analysis of the Chia Gara Formation in the Kirkuk and Hamrin oilfields, North Iraq

The idea of the present work was to combine Rock-Eval pyrolysis and palynofacies analysis in an integrated approach to study 51 source rock cores and cuttings samples collected from the middle Tithonian- Berriasian Chia Gara Formation, in well K-109, Kirkuk Oilfield and well Hr-1 drilled in the Hamrin Oilfield, north of Iraq to evaluate quantitatively and qualitatively the nature of sedimentary organic matter, generation potential and assess thermal maturity of the studied formation in both wells. Rock-Eval pyrolysis and palynofacies data indicate that the Chia Gara Formation in well K-109, Kirkuk Oilfield has kerogen type III/II and II/I and the amorphous organic matter AOM is dense and amber brown to very dark brown in color assigned to type C and D which reflects mature to overmature stage (gas-oil prone). On the other hand, the source rock samples of the Chia Gara Formation encountered in well Hr-1, Hamrin Oilfield has kerogen type II/III and II/I and the AOM is dense rounded, yellow to yellowish brown typeD, mature and is oil-gas prone. The regional tectonic movements and thermal history may cause the diversity in kerogen type and the subtle color variation in the AOM from the Chia Gara Formation in the Kirkuk Field in the north to Hamrin Field in the south.

Sex Differences in Long-eared Owl Plumage Coloration

Abstract Most species of owls lack distinctive sexual color dimorphism, and plumage is not considered reliable for distinguishing sex. In North America, Long-eared Owls (Asio otus) are generally considered monomorphic in color, although there are subtle color differences between the sexes. From 1987 to 2015, we investigated differences in plumage coloration of male and female Long-eared Owls in western Montana. We initially used an observational method (1987–1993), followed by a quantitative method (1994–1999), and then a simplified method (2000–2015). When we used the observational method, we correctly sexed all 22 Long-eared Owls. For the quantitative method, we used a Munsell Soil Color Chart to score underwing coverts, tarsometatarsus, and facial disc of breeding males and females and museum specimens purportedly sexed correctly. We found significant sex-specific color differences: underwing coverts (G = 136.77, df = 5, P < 0.01), tarsometatarsus (G = 44.50, df = 4, P < 0.01), and facial disc (G = 50....

Measuring Color Defects in Flat Panel Displays Using HDR Imaging and Appearance Modeling

Measuring and quantifying color defects in flat panel displays (FPDs) are critical in the FPD industry and related business. Color defects are traditionally investigated by professional human assessors, as color defects are subtle perceptual phenomena that are difficult to detect using a camera system. However, human-based inspection has hindered the quantitative analysis of such color defects. Thus, the industrial automation of color defect measurement in FPDs has been severely limited even by leading manufacturers accordingly. This paper presents a systematic framework for the measurement and numerical evaluation of color defects. Our framework exploits high-dynamic-range imaging to robustly measure physically meaningful quantities of subtle color defects. In addition to the application of advanced imaging technology, an image appearance model is employed to predict the human visual perception of color defects as human assessors do. This proposed automated framework can output quantitative analysis of the color defects. This paper demonstrates the performance of the proposed workflow in investigating subtle color defects in FPDs with a high accuracy.