scholarly journals Seeing the world through the eyes of a butterfly: visual ecology of the territorial males of Pararge aegeria (Lepidoptera: Nymphalidae)

2021 ◽  
Author(s):  
Martin Bergman ◽  
Jochen Smolka ◽  
Dan-Eric Nilsson ◽  
Almut Kelber
Keyword(s):  
Visual Field ◽  
Spatial Resolution ◽  
Visual Environment ◽  
Sexually Dimorphic ◽  
European Forests ◽  
Head Posture ◽  
Pararge Aegeria ◽  
Visual Systems ◽  
The World ◽  
Retinal Region

AbstractCombining studies of animal visual systems with exact imaging of their visual environment can get us a step closer to understand how animals see their “Umwelt”. Here, we have combined both methods to better understand how males of the speckled wood butterfly, Pararge aegeria, see the surroundings of their perches. These males are well known to sit and wait for a chance to mate with a passing females, in sunspot territories in European forests. We provide a detailed description of the males' body and head posture, viewing direction, visual field and spatial resolution, as well as the visual environment. Pararge aegeria has sexually dimorphic eyes, the smallest interommatidial angles of males are around 1°, those of females 1.5°. Perching males face the antisolar direction with their retinal region of the highest resolution pointing at an angle of about 45° above the horizon; thus, looking at a rather even and dark background in front of which they likely have the best chance to detect a sunlit female passing through the sunspot.

scholarly journals Vision and the representation of the surroundings in spatial memory

2011 ◽  
Vol 366 (1564) ◽  
pp. 596-610 ◽  
Author(s):  
Benjamin W. Tatler ◽  
Michael F. Land
Keyword(s):  
Spatial Memory ◽  
Visual Environment ◽  
Coding Scheme ◽  
Perceptual Stability ◽  
The World ◽  
Scene Viewing ◽  
Memory Representations ◽  
The Brain ◽  
Allocentric Representations ◽  
And Task

One of the paradoxes of vision is that the world as it appears to us and the image on the retina at any moment are not much like each other. The visual world seems to be extensive and continuous across time. However, the manner in which we sample the visual environment is neither extensive nor continuous. How does the brain reconcile these differences? Here, we consider existing evidence from both static and dynamic viewing paradigms together with the logical requirements of any representational scheme that would be able to support active behaviour. While static scene viewing paradigms favour extensive, but perhaps abstracted, memory representations, dynamic settings suggest sparser and task-selective representation. We suggest that in dynamic settings where movement within extended environments is required to complete a task, the combination of visual input, egocentric and allocentric representations work together to allow efficient behaviour. The egocentric model serves as a coding scheme in which actions can be planned, but also offers a potential means of providing the perceptual stability that we experience.

4. Motion perception

2017 ◽  
pp. 50-58
Author(s):  
Brian Rogers
Keyword(s):  
Motion Perception ◽  
Apparent Motion ◽  
Time To Contact ◽  
Motion System ◽  
Visual Systems ◽  
Temporal Process ◽  
The World ◽  
Induced Motion ◽  
After Effect ◽  
Spatio Temporal

The ability to detect motion is one of the most important properties of our visual system and the visual systems of nearly every other species. Motion perception is not just important for detecting the movement of objects—both for catching prey and for avoiding predators—but it is also important for providing information about the 3-D structure of the world, for maintaining balance, determining our direction of heading, segregating the scene and breaking camouflage, and judging time-to-contact with other objects in the world. ‘Motion perception’ describes the spatio-temporal process of motion perception and the perceptual effects that tell us something about the characteristics of the motion system: apparent motion, the motion after-effect, and induced motion.

scholarly journals Bias-corrected and spatially disaggregated seasonal forecasts: a long-term reference forecast product for the water sector in semi-arid regions

2020 ◽  
Author(s):  
Christof Lorenz ◽  
Tanja C. Portele ◽  
Patrick Laux ◽  
Harald Kunstmann
Keyword(s):  
Water Management ◽  
Spatial Resolution ◽  
Arid Regions ◽  
Maximum Temperature ◽  
Test Bed ◽  
Seasonal Forecasts ◽  
Blue Nile ◽  
Model Biases ◽  
The World ◽  
Semi Arid

Abstract. Seasonal forecasts have the potential to substantially improve water management particularly in water scarce regions. However, global seasonal forecasts are usually not directly applicable as they are provided at coarse spatial resolutions of at best 36 km and suffer from model biases and drifts. In this study, we therefore apply a bias-correction and spatial-disaggregation (BCSD) approach to seasonal precipitation, temperature and radiation forecasts of the latest long-range seasonal forecasting system SEAS5 of the European Centre for Medium Range Weather Forecasts (ECMWF). As reference we use data from the ERA5-Land offline land surface re-run of the latest ECMWF reanalysis ERA5. By that, we correct for model biases and drifts and improve the spatial resolution from 36 km to 0.1°. This is exemplary performed over 4 predominately semi-arid study domains across the world, which include the river basins of the Karun (Iran), the São Francisco (Brazil), the Tekeze-Atbara and Blue Nile (Sudan, Ethiopia and Eritrea), and the Catamayo-Chira (Ecuador and Peru). Compared against ERA5-Land, the bias-corrected and spatially disaggregated forecasts have a higher spatial resolution and show reduced biases and better agreement of spatial patterns than the raw forecasts. Furthermore, the lead-dependent drift effects are remarkably reduced in the BCSD-forecasts. However, our analysis also showed that computing monthly averages from daily bias-corrected forecasts can lead to statistical inconsistencies particularly during periods and seasons with strong temporal climate gradients or heteroscedasticity. During such periods, particularly the lowest- and highest-lead forecasts can show remaining biases. Our dataset covers the whole (re-)forecast period from 1981 to 2019, for which we provide bias-corrected and spatially disaggregated daily ensemble forecasts for precipitation, average, minimum and maximum temperature as well as for shortwave radiation from the initial date to the coming 214 days. This sums up to more than 100,000 forecasted days for each of the 25 (until the year 2016) and 51 (from the year 2017) ensemble members and each of the 5 analyzed variables. The full repository is made freely available to the public via the World Data Centre for Climate at https://doi.org/10.26050/WDCC/SaWaM_D01_SEAS5_BCSD (Domain D01, Karun Basin (Iran), Lorenz et al., 2020b), https://doi. org/10.26050/WDCC/SaWaM_D02_SEAS5_BCSD (Domain D02: São Francisco Basin (Brazil), Lorenz et al., 2020c), https://doi.org/10.26050/WDCC/SaWaM_D03_SEAS5_BCSD (Domain D03: Tekeze-Atbara and Blue Nile Basins (Ethiopia, Eritrea, Sudan), Lorenz et al., 2020d), and https://doi.org/10.26050/WDCC/SaWaM_D04_SEAS5_BCSD (Domain D04: Catamayo-Chira Basin (Ecuador, Peru), Lorenz et al., 2020a). It is currently the first publicly available daily high-resolution seasonal forecast product that covers multiple regions and variables for such a long period. It hence provides a unique test-bed for evaluating the performance of seasonal forecasts over semi-arid regions and as driving data for hydrological, ecosystem or climate impact models. Therefore, our forecasts provide a crucial contribution for the disaster preparedness and, finally, climate proofing of the regional water management in climatically sensitive regions.

scholarly journals Tree Cover for the Year 2010 of the Metropolitan Region of São Paulo, Brazil

Data ◽  
2019 ◽  
Vol 4 (4) ◽  
pp. 145
Author(s):  
Fabien H. Wagner ◽  
Mayumi C.M. Hirye
Keyword(s):  
Ecosystem Services ◽  
Spatial Resolution ◽  
Urban Forest ◽  
Sao Paulo ◽  
Urban Trees ◽  
Aerial Photographs ◽  
Metropolitan Region ◽  
Tree Cover ◽  
São Paulo ◽  
The World

Mapping urban trees with images at a very high spatial resolution (≤1 m) is a particularly relevant recent challenge due to the need to assess the ecosystem services they provide. However, due to the effort needed to produce these maps from tree censuses or with remote sensing data, few cities in the world have a complete tree cover map. Here, we present the tree cover data at 1-m spatial resolution of the Metropolitan Region of São Paulo, Brazil, the fourth largest urban agglomeration in the world. This dataset, based on 71 orthorectified RGB aerial photographs taken in 2010 at 1-m spatial resolution, was produced using a deep learning method for image segmentation called U-net. The model was trained with 1286 images of size 64 × 64 pixels at 1-m spatial resolution, containing one or more trees or only background, and their labelled masks. The validation was based on 322 images of the same size not used in the training and their labelled masks. The map produced by the U-net algorithm showed an excellent level of accuracy, with an overall accuracy of 96.4% and an F1-score of 0.941 (precision = 0.945 and recall = 0.937). This dataset is a valuable input for the estimation of urban forest ecosystem services, and more broadly for urban studies or urban ecological modelling of the São Paulo Metropolitan Region.

COMPARATIVE ANALYSIS OF PEDAGOGICAL TECHNOLOGIES OF PROFESSIONAL TRAINING OF GRAPHIC DESIGNERS IN UNIVERSITIES OF LEADING COUNTRIES OF THE WORLD

2019 ◽  
pp. 71-83
Author(s):  
Inna Bykhovets
Keyword(s):  
Graphic Design ◽  
Interaction Design ◽  
Information Technologies ◽  
Professional Training ◽  
Rapid Development ◽  
Exhibition Design ◽  
Educational Institutions ◽  
Visual Systems ◽  
Graphic Designer ◽  
The World

The worldwide trend in education is to train a professional who is able to respond quickly to the rapid development of information technologies that extend the graphic designer from the master of illustration, visual systems, advertising, and exhibition design to such areas of graphic design as moving graphics, interaction design, design animation, interactive design. The study found that the peculiarity of such training is the collaboration of educational institutions with enterprises, firms and institutions to make sure that the educational programs offered for students training meet the needs of production, and students really acquire the necessary knowledge, skills and competencies that are modern requirements for competitive graphic design specialist.

The anatomical and physiological properties of the visual cortex argue against cognitive penetration

2016 ◽  
Vol 39 ◽  
Author(s):  
Moshe Gur
Keyword(s):  
Visual Cortex ◽  
Visual Field ◽  
Spatial Resolution ◽  
Image Representation ◽  
Visual Area ◽  
Cognitive Penetration ◽  
Top Down ◽  
Visual Objects ◽  
Physiological Properties ◽  
Perceptual Abilities

AbstractWe are consciously aware of visual objects together with the minute details that characterize each object. Those details are perceived instantaneously and in parallel. V1 is the only visual area with spatial resolution and topographical exactitude matching perceptual abilities. For cognition to penetrate perception, it needs to affect V1 image representation. That is unlikely because of the detailed parallel V1 organization and the nature of top-down connections, which can influence only large parts of the visual field.

Rainbow over Woolsthorpe Manor

1981 ◽  
Vol 36 (1) ◽  
pp. 1-11
Keyword(s):  
Physical Science ◽  
Geometric Theory ◽  
Natural World ◽  
Human Cortex ◽  
Conical Shells ◽  
Visual Systems ◽  
Dynamic Forces ◽  
The World

ONE of the glories of the natural world is the rainbow. Water, moulded into near-spheres by molecular and dynamic forces, refracts, reflects and diffracts light to yield conical shells of enhanced irradiance for each Sunobserver axis. For observers with frequency-discriminating visual systems, the result is that chromatic apparition, a rainbow. The theory of the rainbow has challenged many men over the centuries, including Aristotle, Descartes, Newton, Young, Airy, and Mie. It was Newton who appreciated first ‘the true origin of colours’ and extended Descartes’s geometric theory to explain the colours of the rainbow. Newton realized also that ‘the rays to speak properly are not coloured’, and thus that the colours of the world, with its flowers and rainbows, are but constructs of the human cortex. This and more appear in his Opticks , one of the classics of physical science.

scholarly journals Studying SARS-CoV-2 with Fluorescence Microscopy

2021 ◽  
Vol 22 (12) ◽  
pp. 6558
Author(s):  
Lidia V. Putlyaeva ◽  
Konstantin A. Lukyanov
Keyword(s):  
Molecular Biology ◽  
Fluorescence Microscopy ◽  
Spatial Resolution ◽  
Super Resolution ◽  
High Specificity ◽  
Fluorescence Labeling ◽  
World Community ◽  
The World ◽  
Fundamental Research ◽  
Diagnostics And Therapy

The COVID-19 pandemic caused by SARS-CoV-2 coronavirus deeply affected the world community. It gave a strong impetus to the development of not only approaches to diagnostics and therapy, but also fundamental research of the molecular biology of this virus. Fluorescence microscopy is a powerful technology enabling detailed investigation of virus–cell interactions in fixed and live samples with high specificity. While spatial resolution of conventional fluorescence microscopy is not sufficient to resolve all virus-related structures, super-resolution fluorescence microscopy can solve this problem. In this paper, we review the use of fluorescence microscopy to study SARS-CoV-2 and related viruses. The prospects for the application of the recently developed advanced methods of fluorescence labeling and microscopy—which in our opinion can provide important information about the molecular biology of SARS-CoV-2—are discussed.

scholarly journals Visual search without central vision – no single pseudofovea location is best

2014 ◽  
Vol 7 (2) ◽  
Author(s):  
Angelika Lingnau ◽  
Thorsten Albrecht ◽  
Jens Schwarzbach ◽  
Dirk Vorberg
Keyword(s):  
Visual Search ◽  
Macular Degeneration ◽  
Spatial Resolution ◽  
Central Vision ◽  
Foveal Vision ◽  
Scan Path ◽  
Path Direction ◽  
Retinal Region ◽  
Field Location

We typically fixate targets such that they are projected onto the fovea for best spatial resolution. Macular degeneration patients often develop fixation strategies such that targets are projected to an intact eccentric part of the retina, called pseudofovea. A longstanding debate concerns which pseudofovea-location is optimal for non-foveal vision. We examined how pseudofovea position and eccentricity affect performance in visual search, when vision is restricted to an off-foveal retinal region by a gaze-contingent display that dynamically blurs the stimulus except within a small viewing window (forced field location). Trained normally sighted participants were more accurate when forced field location was congruent with the required scan path direction; this contradicts the view that a single pseudofovea location is generally best. Rather, performance depends on the congruence between pseudofovea location and scan path direction.

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