color pattern Dotaz Zobrazit nápovědu
In a previous study, we found that the shape of a bird, rather than its color, plays a major role in the determination of human preferences. Thus, in the present study, we asked whether the preferences of human respondents towards uniformly shaped, colorful birds are determined by pattern rather than color. The experimental stimuli were pictures of small passerine birds of the family Pittidae possessing uniform shape but vivid coloration. We asked 200 participants to rank 43 colored and 43 identical, but grayscaled, pictures of birds. To find the traits determining human preferences, we performed GLM analysis in which we tried to explain the mean preference ranks and PC axes by the following explanatory variables: the overall lightness and saturation, edges (pattern), and the portion of each of the basic color hues. The results showed that the mean preference ranks of the grayscale set is explained mostly by the birds' pattern, whereas the colored set ranking is mostly determined by the overall lightness. The effect of colors was weaker, but still significant, and revealed that people liked blue and green birds. We found no significant role of the color red, the perception of which was acquired relatively recently in evolution.
- MeSH
- barva * MeSH
- emoce MeSH
- estetika psychologie MeSH
- lidé MeSH
- ptáci klasifikace MeSH
- světelná stimulace metody MeSH
- vnímání barev * MeSH
- výběrové chování fyziologie MeSH
- zrak MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
The number of L cones in the retina normally exceeds that of the M cones. Because normal color vision does not depend on the ratio of L- and M-photoreceptors, their signals must undergo an alteration in gain before being analyzed in the cortex. Previous studies have shown that this gain must take place before the cortex, but after the bipolar/amacrine cell layer of the retina. The aim of this study was to obtain topographical information about L- and M-cone activity at the ganglion cell layer using multifocal pattern electroretinography (mfPERG). A standard (black and white) stimulus was used, as well as stimuli modulating only the long wavelength-sensitive (L) or only the middle wavelength-sensitive (M) cones. The L:M ratio was calculated from the amplitude of the L-cone isolating mfPERG to that of the M-cone isolating mfPERG of 10 trichromats. Both the positive and negative components of the waveform were analyzed. Additional recordings of single cone modulated mfERGs were obtained from nine of the 10 subjects. We also recorded from one protanope and one deuteranope. The L:M cone amplitude ratios for both deflections of the mfPERG in the trichromats were around unity (medians 1.18 and 1.16, respectively) for the central 8 degrees of retina. In the peripheral retina between 12.8 degrees and 26 degrees , this ratio increased to 1.42 for the positive component, and 1.37 for the negative component. The median L:M cone amplitude ratios for the mfPERG were higher and ranged between 1.00-2.78 in the central 8 degrees and 1.29-2.78 in the periphery. The results indicate that a major gain adjustment of the retinal signals takes place at the ganglion cell level, and that the ratio is higher at eccentric locations than in the central retinal area.
- MeSH
- barva MeSH
- čípky retiny patofyziologie MeSH
- citlivost na kontrast fyziologie MeSH
- dospělí MeSH
- elektroretinografie * MeSH
- lidé MeSH
- poruchy barevného vidění patofyziologie MeSH
- psychofyzika MeSH
- reakční čas MeSH
- senzorické prahy fyziologie MeSH
- světelná stimulace metody MeSH
- testy barvocitu MeSH
- vnímání barev MeSH
- zraková pole fyziologie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Red hair is associated in women with pain sensitivity. This medical condition, and perhaps others, seems facilitated by the combination of being red-haired and female. We tested this hypothesis by questioning a large sample of Czech and Slovak respondents about the natural redness and darkness of their hair, their natural eye color, their physical and mental health (24 categories), and other personal attributes (height, weight, number of children, lifelong number of sexual partners, frequency of smoking). Red-haired women did worse than other women in ten health categories and better in only three, being particularly prone to colorectal, cervical, uterine, and ovarian cancer. Red-haired men showed a balanced pattern, doing better than other men in three health categories and worse in three. Number of children was the only category where both male and female redheads did better than other respondents. We also confirmed earlier findings that red hair is naturally more frequent in women than in men. Of the 'new' hair and eye colors, red hair diverges the most from the ancestral state of black hair and brown eyes, being the most sexually dimorphic variant not only in population frequency but also in health status. This divergent health status may have one or more causes: direct effects of red hair pigments (pheomelanins) or their by-products; effects of other genes that show linkage with genes involved in pheomelanin production; excessive prenatal exposure to estrogen (which facilitates expression of red hair during fetal development and which, at high levels, may cause health problems later in life); evolutionary recentness of red hair and corresponding lack of time to correct negative side effects; or genetic incompatibilities associated with the allele Val92Met, which seems to be of Neanderthal origin and is one of the alleles that can cause red hair.
- MeSH
- barva očí * MeSH
- barva vlasů * MeSH
- lidé MeSH
- sexuální faktory * MeSH
- zdravotní stav * MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
- Slovenská republika MeSH
Precision fish farming is an emerging concept in aquaculture research and industry, which combines new technologies and data processing methods to enable data-based decision making in fish farming. The concept is based on the automated monitoring of fish, infrastructure, and the environment ideally by contactless methods. The identification of individual fish of the same species within the cultivated group is critical for individualized treatment, biomass estimation and fish state determination. A few studies have shown that fish body patterns can be used for individual identification, but no system for the automation of this exists. We introduced a methodology for fully automatic Atlantic salmon (Salmo salar) individual identification according to the dot patterns on the skin. The method was tested for 328 individuals, with identification accuracy of 100%. We also studied the long-term stability of the patterns (aging) for individual identification over a period of 6 months. The identification accuracy was 100% for 30 fish (out of water images). The methodology can be adapted to any fish species with dot skin patterns. We proved that the methodology can be used as a non-invasive substitute for invasive fish tagging. The non-invasive fish identification opens new posiblities to maintain the fish individually and not as a fish school which is impossible with current invasive fish tagging.
Complex visual signaling through various combinations of colors and patterns has been well documented in a number of diurnal reptiles. However, there are many nocturnal species with highly sensitive vision, being able to discriminate colors in night conditions, as was shown in geckos. Because of their sensitivity to chromatic signals, including UV (ultraviolet), they may have potential hidden features in their coloration, which may play role in intraspecific communication (e.g. mate choice) or interspecific signals (e.g. antipredatory function). We explored this hypothesis in nocturnal Leopard geckos (Eublepharis macularius), a species using visual signals in both antipredation defense and courtship, having ontogenetic color change accompanied by a shift in behavior. We used UV photography and visual modeling in order to compare various aspects of their coloration (luminance, contrast, color proportions) between sexes, age groups and populations. We found that Leopard geckos have considerable UV reflectance in white patches on their tails (and on the head in juveniles). Though, no prominent differences were detected in their coloration between various groups. We hypothesize that the limitation of UV reflectance to the head and tail, which are both actively displayed during defense, especially in juveniles, might potentially boost the effect of antipredation signaling.
- Klíčová slova
- Antipredation, Squamata, UV, Visual modeling, Visual signaling,
- MeSH
- ještěři fyziologie MeSH
- noční vidění fyziologie MeSH
- rozpoznávání obrazu fyziologie MeSH
- sexuální faktory MeSH
- světelná stimulace MeSH
- ultrafialové záření MeSH
- věkové faktory MeSH
- vidění barevné fyziologie MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Color polymorphism offers rich opportunities for studying the eco-evolutionary mechanisms that drive the adaptations of local populations to heterogeneous and changing environments. We explored the color morph diversity and composition in a Chrysomela lapponica leaf beetle across its entire distribution range to test the hypothesis that environmental and climatic variables shape spatiotemporal variation in the phenotypic structure of a polymorphic species. We obtained information on 13 617 specimens of this beetle from museums, private collections, and websites. These specimens (collected from 1830-2020) originated from 959 localities spanning 33° latitude, 178° longitude, and 4200 m altitude. We classified the beetles into five color morphs and searched for environmental factors that could explain the variation in the level of polymorphism (quantified by the Shannon diversity index) and in the relative frequencies of individual color morphs. The highest level of polymorphism was found at high latitudes and altitudes. The color morphs differed in their climatic requirements; composition of colour morphs was independent of the geographic distance that separated populations but changed with collection year, longitude, mean July temperature and between-year temperature fluctuations. The proportion of melanic beetles, in line with the thermal melanism hypothesis, increased with increasing latitude and altitude and decreased with increasing climate seasonality. Melanic morph frequencies also declined during the past century, but only at high latitudes and altitudes where recent climate warming was especially strong. The observed patterns suggest that color polymorphism is especially advantageous for populations inhabiting unpredictable environments, presumably due to the different climatic requirements of coexisting color morphs.
- Klíčová slova
- adaptive polymorphism, color morphs, evolutionary dynamics, geographic variation, phenotypic diversity, thermal melanism,
- MeSH
- aklimatizace MeSH
- barva MeSH
- biologická evoluce MeSH
- brouci * genetika MeSH
- nadmořská výška MeSH
- teplota MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
INTRODUCTION: The presence of a velocity in isovolumic contraction phase (Vivc) evaluated using tissue Pulse wave Doppler myocardial imaging (PWDMI) correlates with a transmural extent of scar after myocardial infarction. The possible clinical usefulness of Vivc evaluated using color Doppler myocardial imaging (CDMI) in detection of a scar after myocardial infarction extent in patients with coronary heart disease (CHD) and low LV systolic function remains to be clarified. PATIENTS AND METHODS: 57 patients with CHD (average LVEF 33.5±5%), examined echocardiographicaly (17-segment LV model, 689 segments evaluated) and by cardiac magnetic resonance. All segments were scanned for Vivc presence using CDMI. Vivc presence/absence was correlated with signs of a scar after MI in all segments and in akinetic segments separately. RESULTS: We found significantly larger values of wall thickness (8.2±2,2 vs. 7.1±1.9, p<0.0001), significantly lower values of average late enhancement (LE) extent (1.32±1.78 vs. 1.66±1.98, p=0.041) and LE/wall thickness ratio (20.1±29.8 vs. 29.6±36.7, p=0.008) in segments with present Vivc. Vivc presence in a segment with an abnormal wall motion had a sensitivity of 72.9% and a specificity of 35.7% in recognizing a segment without a transmural scar (LE/ wall thickness ratio ≤75%). Vivc absence in a segment with an abnormal wall motion had a sensitivity of 72.7% and a specificity of 41.2% in recognizing a segment with a transmural scar (LE/wall thickness ratio ≥75%). CONCLUSIONS: Isovolumic velocities evaluation assessed using color Doppler myocardial imaging is not applicable in a real-world clinical setting. The presence or absence of a velocity pattern during LV isovolumic contraction is not useful in in the assessment of a post-infarction scar transmurality.
- MeSH
- barevná dopplerovská echokardiografie * MeSH
- infarkt myokardu diagnostické zobrazování patologie MeSH
- jizva diagnostické zobrazování etiologie MeSH
- kontrakce myokardu MeSH
- koronární nemoc diagnostické zobrazování patofyziologie MeSH
- lidé MeSH
- magnetická rezonanční tomografie MeSH
- myokard patologie MeSH
- odchylka pozorovatele MeSH
- senioři MeSH
- senzitivita a specificita MeSH
- tepový objem * MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Fabry disease is an X-linked genetic disorder characterized by progressive intracellular accumulation of neutral glycosphingolipids. Cardiac involvement is frequent and left ventricular (LV) diastolic dysfunction is present in most of the affected subjects. Pulsed-wave tissue Doppler echocardiography (PW-TDE) and color M-mode are new Doppler methods for LV diastolic function evaluation. Their role in the assessment of Fabry disease-related cardiomyopathy remains to be established. In this study we aimed to determine the utility of PW-TDE and color M-mode-derived parameters in the assessment of LV diastolic function in patients with Fabry disease. Eighty-one echocardiographic examinations performed in 35 patients affected by Fabry disease were retrospectively analyzed. Early diastolic lateral mitral annular velocity (E(m)) determined by PW-TDE and color M-mode flow propagation velocity (V(p)) were measured and compared to LV filling patterns obtained using standard Doppler indexes. The receiver operating characteristics (ROC) curves method was used to determine the summary measure of relative accuracy for E(m) and V(p). A comparison of ROC curves showed a significant difference for areas under the curve in favor of E(m) (P < 0.001). Pseudonormal filling pattern, higher LV mass index, higher relative wall thickness, larger left atrial diameter, and older age were more frequent (all P < 0.001) in patients with incorrect diagnosis of normal LV diastolic function based on the measurement of V(p). E(m) appears to be superior to V(p) in the assessment of LV diastolic function in patients with Fabry disease. V(p) fails to detect abnormal LV diastolic function in subjects with pronounced concentric LV remodeling and pseudonormal filling pattern.
- MeSH
- barevná dopplerovská echokardiografie * MeSH
- dospělí MeSH
- dysfunkce levé srdeční komory diagnostické zobrazování patofyziologie MeSH
- Fabryho nemoc diagnostické zobrazování patofyziologie MeSH
- falešně negativní reakce MeSH
- funkce levé komory srdeční * MeSH
- hypertrofie levé komory srdeční diagnostické zobrazování patofyziologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- mitrální chlopeň diagnostické zobrazování patofyziologie MeSH
- plocha pod křivkou MeSH
- počítačové zpracování obrazu MeSH
- pulzní dopplerovská echokardiografie MeSH
- remodelace komor MeSH
- retrospektivní studie MeSH
- rychlost toku krve MeSH
- senzitivita a specificita MeSH
- srdeční síně diagnostické zobrazování patofyziologie MeSH
- tepový objem * MeSH
- výzkumný projekt MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
In this paper, we examine intraspecific variation in the quantity of alkaloid chemical defence in field collected individuals of the polymorphic ladybird beetle Adalia decempunctata (10-spot ladybird). Like its more widely studied relative Adalia bipunctata (2-spot ladybird), A. decempunctata possesses the alkaloids adaline and adalinine, which are, respectively, the major and minor alkaloids of A. bipunctata. We focused especially on alkaloid concentration in relation to colour pattern morph, sex, and the relationship between female and egg parameters. There was a marked sexual dimorphism in the balance of the two alkaloids, with adaline predominating in females and adalinine predominating in males: in males, on average, over 70% of total alkaloid was adalinine. Females had a lower proportion of adalinine (< 10%) than their eggs (> 15%) and relationships between egg alkaloid and female alkaloid or fecundity were weak or non-existent. Colour pattern morph had a borderline (although not) significant relationship with adaline concentration and total alkaloid concentration, which could be further explored with laboratory reared individuals. The sexual dimorphism in alkaloid content, which seems likely due to differences in synthesis, might be related to their relative costs to the two sexes and might provide insight into the evolution of alkaloid diversity in ladybirds.
- Klíčová slova
- Aposematism, Chemical defence, Color morph, Polymorphism, Reproductive allocation, Sexual dimorphism,
- MeSH
- alkaloidy * analýza chemie metabolismus MeSH
- barva MeSH
- brouci * fyziologie chemie MeSH
- druhová specificita MeSH
- ovum chemie MeSH
- pigmentace MeSH
- pohlavní dimorfismus MeSH
- rozmnožování * MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- alkaloidy * MeSH
Images of ocular fundus are routinely utilized in ophthalmology. Since an examination using fundus camera is relatively fast and cheap procedure, it can be used as a proper diagnostic tool for screening of retinal diseases such as the glaucoma. One of the glaucoma symptoms is progressive atrophy of the retinal nerve fiber layer (RNFL) resulting in variations of the RNFL thickness. Here, we introduce a novel approach to capture these variations using computer-aided analysis of the RNFL textural appearance in standard and easily available color fundus images. The proposed method uses the features based on Gaussian Markov random fields and local binary patterns, together with various regression models for prediction of the RNFL thickness. The approach allows description of the changes in RNFL texture, directly reflecting variations in the RNFL thickness. Evaluation of the method is carried out on 16 normal ("healthy") and 8 glaucomatous eyes. We achieved significant correlation (normals: ρ=0.72±0.14; p≪0.05, glaucomatous: ρ=0.58±0.10; p≪0.05) between values of the model predicted output and the RNFL thickness measured by optical coherence tomography, which is currently regarded as a standard glaucoma assessment device. The evaluation thus revealed good applicability of the proposed approach to measure possible RNFL thinning.
- Klíčová slova
- Fundus images, Glaucoma, Local binary patterns, Markov random fields, Retinal nerve fiber layer, Texture analysis,
- MeSH
- barva * MeSH
- discus nervi optici patologie MeSH
- fundus oculi MeSH
- glaukom patologie MeSH
- lidé MeSH
- Markovovy řetězce * MeSH
- nervová vlákna patologie MeSH
- normální rozdělení MeSH
- optická koherentní tomografie MeSH
- retinální gangliové buňky patologie MeSH
- vylepšení obrazu metody MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH