Visual Recognition in the Peripheral Field: Letters versus Symbols and Adults versus Children

Perception ◽  
1993 ◽  
Vol 22 (1) ◽  
pp. 77-90 ◽  
Author(s):  
Olga Zegarra-Moran ◽  
Gad Geiger
Keyword(s):  
Visual Acuity ◽  
Visual Recognition ◽  
Letter Recognition ◽  
The Other ◽  
Subject Group ◽  
Lateral Masking ◽  
Visual Strategy ◽  
Large Size

The plot of the form-resolving field (FRF) was obtained by tachistoscopically presenting two figures in each stimulus, one in the center of gaze and the other in the peripheral field. The figures in the periphery were placed at various eccentricities in different presentations. The ensuing plot of average letter recognition as a function of eccentricity is the FRF. Only the horizontal components of the FRFs were used in the comparisons. Three sets of figures were used as stimuli: regular-size letters, large-size letters, and symbols. Three groups of subjects were compared: adult ordinary readers, reading children, and pre-reading-age children. The last were tested with symbols only. In letter recognition, the FRFs for young and adult ordinary readers are similar and fall off monotonically and symmetrically with eccentricity, hence conforming with the first Aubert—Foerster law (1857). However, the FRFs tested with symbols are narrower than those tested with letters of the same sizes and stroke widths, which is not in accordance with the first Aubert—Foerster law. In addition, the FRFs of symbols are different for each subject group. It is suggested that recognition in the peripheral field is not determined by visual acuity alone; rather, it is further confined or determined by the visual strategy employed to accomplish the task, and its associated distribution of lateral masking.

Descriptions of the larvae of four species of Procladius from Great Slave Lake (Chironomidae:Diptera)

1978 ◽  
Vol 56 (9) ◽  
pp. 2055-2057 ◽  
Author(s):  
J. W. Moore ◽  
I. A. Moore
Keyword(s):  
Antennal Segment ◽  
The Other ◽  
Large Size ◽  
Great Slave Lake ◽  
Palpal Segment ◽  
Almost All

Descriptions of larvae of Procladius denticulatus, Procladius culiciformis, Procladius freemani, and Procladius bellus collected from Yellowknife Bay (lat., 62°25′; long., 114°20′) are given. Procladius denticulatus was separated from the other species by its large size, a character which always proved distinctive. Procladius culiciformis and P. freemani were separated from one another through several measurements including those of the basal antennal segment and the basal palpal segment. Almost all characters of the head were useful in distinguishing the much smaller P. bellus from the other species.

A giant within Carpocorini (Hemiptera: Heteroptera: Pentatomidae): Description of Adustonotus graziae sp. nov.

Zootaxa ◽  
2021 ◽  
Vol 4958 (1) ◽  
pp. 489-502
Author(s):  
FILIPE MICHELS BIANCHI
Keyword(s):  
Morphological Characters ◽  
The Other ◽  
Total Evidence ◽  
Valid Species ◽  
Phylogenetic Position ◽  
New Taxon ◽  
Large Size ◽  
Internal Genitalia ◽  
Evidence Analysis ◽  
Heteroptera Pentatomidae

The Carpocorini are distributed worldwide, and it is one of the most speciose tribes within the Pentatomidae with 127 genera and more than 500 valid species. Recently, Adustonotus Bianchi was described to contain eight species formerly placed within Euschistus Dallas. Among them, Adustonotus grandis (Rolston) and Adustonotus latus (Dallas) are remarkable for their large size. Herein, the phylogenetic position of a new taxon is inferred by a total evidence analysis based on 85 morphological characters and four molecular markers. Adustonotus graziae sp. nov. is described, and is recovered in a polytomic lineage, including A. grandis and A. latus. These species share a solid combination of features that enable them to be separated from the other Adustonotus species (e.g., large size, the humeral angles spatulate and exceptionally produced, and the capsula seminalis shortened). Illustrations of external and internal genitalia, and a distributional map are provided. 

scholarly journals Survival analysis of orange tree varieties in Spain

2019 ◽  
Vol 17 (1) ◽  
pp. e0103 ◽  
Author(s):  
Francisco Alcon ◽  
M. Angeles Fernández-Zamudio ◽  
Erasmo I. López-Becerra ◽  
M. Dolores De-Miguel
Keyword(s):  
Survival Analysis ◽  
Frost Resistance ◽  
Fruit Fly ◽  
Duration Analysis ◽  
Point Of View ◽  
The Other ◽  
Optimal Result ◽  
Large Size ◽  
Analysis Technique ◽  
Level Of Significance

The fundamental basis of Spanish citriculture is its varietal composition, which contributes to the existence of a marketing calendar that extends to almost the entire year. As time goes by, the supply of varieties is continuously renewed, requiring significant investments by growers. The guarantee of a quality supply to the markets, on one hand, and the optimal result of the investments made, on the other, require that, in managing the sector, the characteristics determining the survival of the varieties be taken into account. The main purpose of this study was therefore to assess the influence of the attributes affecting the longevity of orange plantations from a technical and commercial point of view. The duration analysis technique applied to the different varieties has been used. The main attributes determining the elimination of a variety were the presence of seeds in the fruit and the tendency towards a decrease in surface size. Permanence- or survival-friendly attributes included the calibre (large size of the variety, within its group) and the price received by farmers. Precocity, frost resistance, commercial quality and resistance to fruit fly did not have the expected level of significance.

Binding SNOMED CT Terms to Archetype Elements

2015 ◽  
Vol 54 (01) ◽  
pp. 45-49 ◽  
Author(s):  
J. Bermudez ◽  
A. Illarramendi ◽  
I. Berges
Keyword(s):  
Electronic Health Records ◽  
Health Systems ◽  
The Other ◽  
Snomed Ct ◽  
Health Records ◽  
Large Size ◽  
Level Of Confidence ◽  
Comparison Methods ◽  
String Comparison ◽  
Text Information

SummaryIntroduction: This article is part of the Focus Theme of Methods of Information in Medicine on “Managing Interoperability and Complexity in Health Systems”.Background: The proliferation of archetypes as a means to represent information of Electronic Health Records has raised the need of binding terminological codes – such as SNOMED CT codes – to their elements, in order to identify them univocally. However, the large size of the terminologies makes it difficult to perform this task manually.Objectives: To establish a baseline of results for the aforementioned problem by using off-the-shelf string comparison-based techniques against which results from more complex techniques could be evaluated.Methods: Nine Typed Comparison Methods were evaluated for binding using a set of 487 archetype elements. Their recall was calculated and Friedman and Nemenyi tests were applied in order to assess whether any of the methods outperformed the others.Results: Using the qGrams method along with the ‘Text’ information piece of archetype elements outperforms the other methods if a level of confidence of 90% is considered. A recall of 25.26% is obtained if just one SNOMED CT term is retrieved for each archetype element. This recall rises to 50.51% and 75.56% if 10 and 100 elements are retrieved respectively, that being a reduction of more than 99.99% on the SNOMED CT code set.Conclusions: The baseline has been established following the above-mentioned results. Moreover, it has been observed that although string comparison-based methods do not outperform more sophisticated techniques, they still can be an alternative for providing a reduced set of candidate terms for each archetype element from which the ultimate term can be chosen later in the more-than-likely manual supervision task.

scholarly journals Predation selects for smaller eye size in a vertebrate: effects of environmental conditions and sex

2019 ◽  
Vol 286 (1897) ◽  
pp. 20182625 ◽  
Author(s):  
Richard Svanbäck ◽  
Frank Johansson
Keyword(s):  
Visual Acuity ◽  
Phenotypic Plasticity ◽  
Experimental Evidence ◽  
Predation Risk ◽  
Environmental Conditions ◽  
Retinal Image ◽  
The Other ◽  
Eye Size ◽  
Fish Predators ◽  
Resource Levels

Increased eye size in animals results in a larger retinal image and thus improves visual acuity. Thus, larger eyes should aid both in finding food as well as detecting predators. On the other hand, eyes are usually very conspicuous and several studies have suggested that eye size is associated with predation risk. However, experimental evidence is scant. In this study, we address how predation affects variation in eye size by performing two experiments using Eurasian perch juveniles as prey and either larger perch or pike as predators. First, we used large outdoor tanks to compare selection due to predators on relative eye size in open and artificial vegetated habitats. Second, we studied the effects of both predation risk and resource levels on phenotypic plasticity in relative eye size in indoor aquaria experiments. In the first experiment, we found that habitat altered selection due to predators, since predators selected for smaller eye size in a non-vegetated habitat, but not in a vegetated habitat. In the plasticity experiment, we found that fish predators induced smaller eye size in males, but not in females, while resource levels had no effect on eye size plasticity. Our experiments provide evidence that predation risk could be one of the driving factors behind variation in eye size within species.

scholarly journals Rubeola keratitis emergence during a recent measles outbreak in New Zealand

2020 ◽  
Vol 12 (3) ◽  
pp. 289
Author(s):  
Aaron P.C. Ong ◽  
Adam Watson ◽  
Shanu Subbiah
Keyword(s):  
Visual Acuity ◽  
New Zealand ◽  
The Other ◽  
Effective Vaccine ◽  
Eye Drops ◽  
Corneal Perforation ◽  
Ocular Complications ◽  
Measles Outbreak ◽  
Recent Outbreak ◽  
Baseline Visual Acuity

ABSTRACT INTRODUCTIONMeasles is a highly contagious disease caused by the rubeola virus. It can result in ocular complications such as conjunctivitis and keratitis, which will be encountered in general practice. Cases usually resolve without sequelae, but may progress to corneal perforation if left untreated. AIMWe present two cases of rubeola keratitis secondary to measles infection. METHODSThis report is about a retrospective review of data from two patients who presented to the eye department with rubeola keratitis in the midst of the recent measles outbreak in New Zealand. RESULTSBoth patients presented with decreased visual acuity approximately 2 weeks after being diagnosed with measles. One of them was unvaccinated, whereas the other had no documentation of previous vaccination. Both were healthy and immunocompetent individuals. There was no evidence of corneal perforation or retinopathy on examination. Both patients regained their baseline visual acuity after treatment with fluorometholone eye drops. DISCUSSIONDespite the existence of a safe and effective vaccine, there were more than 2000 cases of measles in the recent outbreak in New Zealand. The lack of vaccination is one of the primary causes of rubeola keratitis. These cases highlight the effects of measles infection from an ophthalmology perspective and reinforce the paramount importance of getting vaccinated.

scholarly journals A lateral masking effect in tactile and blurred visual letter recognition

1976 ◽  
Vol 20 (4) ◽  
pp. 221-226 ◽  
Author(s):  
Jack M. Loomis ◽  
Patricia Apkarian-Stielau
Keyword(s):  
Letter Recognition ◽  
Masking Effect ◽  
Lateral Masking

The dorsal eye of the mayfly Atalophlebia (Ephemeroptera)

1978 ◽  
Vol 200 (1139) ◽  
pp. 137-150 ◽  
Keyword(s):  
Visual Pigment ◽  
Current Flow ◽  
Yellow Pigment ◽  
The Other ◽  
Retinula Cell ◽  
Clear Zone ◽  
Large Size ◽  
Sharp Focus ◽  
Pigment Distribution ◽  
Light Guides

The dorsal eye of Atalophlebia has two unusual features, the sensitivity only to ultraviolet (u. v.) light, and the candelabra-shaped rhabdom. In addition, the crystalline cone is surrounded to its tip by a yellow pigment, and the tip tapers gradually as a dense fibre. These details, particularly the pigment distribution, indicate that a superposition image cannot be formed by u. v. light. Also, there is no refracting or reflecting structure that could form a sharp superposition image. Instead, it is suggested that u. v. rays are sharply focused on the cone tip and conducted by the retinula cell columns acting as light guides across the clear zone. Light of longer wavelength, on the other hand, is partially focused through the yellow pigment, and, although it is not seen by the insect, it is available to photoregenerate the visual pigment. This method of boosting sensitivity is appropriate for a pure u. v. eye and does not require a sharp focus of the regenerative rays, although the clear zone is an essential part of the mechanism. The rhabdom has an extraordinary shape like a flat 5-armed candelabra in cross section, with five posteriorly directed arms which are formed by six retinula cells. There is also a 7th retinula cell without a rhabdomere. This cell penetrates laterally the rhabdom of the other six, and also forms a sheath around half of its own ommatidium and half of the the adjacent ommatidium. The exceptional relations between this cell, and the other six, together with the orientated candelabra pattern of the rhabdom, and the large size of the 7th retinula axon, is interpreted as a way of enhancing the current flow down the 7th axon which runs direct to the medulla, bypassing the lamina.

A large and enigmatic new eleutherodactyline frog (Anura, Strabomantidae) from Serra do Sincora Espinhaco range, Northeastern Brazil

Zootaxa ◽  
2008 ◽  
Vol 1761 (1) ◽  
pp. 59 ◽  
Author(s):  
JOSÉ CASSIMIRO ◽  
VANESSA K. VERDADE ◽  
MIGUEL T. RODRIGUES
Keyword(s):  
New Species ◽  
Central America ◽  
The Other ◽  
Northeastern Brazil ◽  
Head Width ◽  
Mountain Range ◽  
Campos Rupestres ◽  
Espinhaço Range ◽  
Large Size ◽  
A New Species

We describe a new species of a large eleutherodactyline frog from the mountain rocky meadows (“campos rupestres”) of the Serra do Sincorá, Espinhaço mountain range, Mucugê municipality, State of Bahia, Brazil. The new species is promptly diagnosed from all the other Brazilian eleutherodactylines by its large size (males SVL 40.3–41.1; females SVL 75.2–79.7mm), broad head (head width 43–49% of SVL), presence of frontoparietal crests, pars fascialis of the maxilla deepened, discs absent on fingers, toes with poorly developed discs, first and second toes ridged, and tarsal fold absent. On the basis of these characters the new species is attributed to the genus Strabomantis up to now restricted to southern part of Central America and northwest part of South America.

Sex Differences and Initial Reading Performance

1980 ◽  
Vol 46 (2) ◽  
pp. 523-526 ◽  
Author(s):  
Norman M. Chansky ◽  
Joanne Czernik ◽  
James Duffy ◽  
Lillian Finnell
Keyword(s):  
Sex Differences ◽  
Cross Validation ◽  
First Grade ◽  
Reading Performance ◽  
Letter Recognition ◽  
The Other ◽  
Regression Equations ◽  
Similar Accuracy ◽  
Initial Reading ◽  
School Records

400 school records were randomly selected from school files, equally divided between boys and girls. Kindergarten Letter Recognition and Number Readiness scores were then correlated with subsequent first-grade achievement. Regression equations were developed for half of each sample and applied to the other half. This produced Calibration and Cross-validation samples for each sex. Although girls' means were significantly higher than boys' the magnitude of difference was not deemed psychologically relevant. Sex did not moderate the relationships between any predictor with any criterion. Letter recognition and number readiness predicted first-grade reading with similar accuracy. Finally, each criterion correlated only slightly higher with several predictors combined than it did with each predictor separately.

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