Search results for " Structures"
showing 10 items of 4162 documents
There is more to accommodation of the eye than simply minimizing retinal blur
2017
Eyes of children and young adults change their optical power to focus nearby objects at the retina. But does accommodation function by trial and error to minimize blur and maximize contrast as is generally accepted? Three experiments in monocular and monochromatic vision were performed under two conditions while aberrations were being corrected. In the first condition, feedback was available to the eye from both optical vergence and optical blur. In the second, feedback was only available from target blur. Accommodation was less precise for the second condition, suggesting that it is more than a trial-and-error function. Optical vergence itself seems to be an important cue for accommodation.
A new trifocal corneal inlay for presbyopia
2021
[EN] Corneal inlays (CIs) are the most recent surgical procedure for the treatment of presbyopia in patients who want complete independence from the use of glasses or contact lenses. Although refractive surgery in presbyopic patients is mostly performed in combination with cataract surgery, when the implantation of an intraocular lens is not necessary, the option of CIs has the advantage of being minimally invasive. Current designs of CIs are, either: small aperture devices, or refractive devices, however, both methods do not have good performance simultaneously at intermediate and near distances in eyes that are unable to accommodate. In the present study, we propose the first design of a …
When virtual and real worlds coexist: Visualization and visual system affect spatial performance in augmented reality
2021
New visualization approaches are being actively developed aiming to mitigate the effect of vergence-accommodation conflict in stereoscopic augmented reality; however, high interindividual variability in spatial performance makes it difficult to predict user gain. To address this issue, we investigated the effects of consistent and inconsistent binocular and focus cues on perceptual matching in the stereoscopic environment of augmented reality using a head-mounted display that was driven in multifocal and single focal plane modes. Participants matched the distance of a real object with images projected at three viewing distances, concordant with the display focal planes when driven in the mu…
Ultraviolet reflectance of male nuptial colouration in sand lizards (Lacerta agilis) from the Pyrenees
2007
Abstract The evolutionary significance of lacertid colourations is relatively unexplored. However, several studies have demonstrated signalling by means of bright green colouration in Swedish Lacerta agilis males during the breeding season. Unfortunately, most of these studies have been based on human colour perception that differs in several ways from that of lizard. An important difference between human and lizard colour vision is the presence of an ultraviolet (UV) sensitive cone in lizards. The available evidence suggests that male sand lizards colorations do not reflect UV wavelengths, at least in Swedish populations. However, this study, based on objective (spectrophotometric) measur…
HOW MUCH DANGEROUS IS CT ACCORDING TO PATIENTS AND HOW DOES DOSE BILL AFFECT THEIR PERCEPTION OF IONIZING RADIATION?
2015
Aims and objectives Methods and materials Results Conclusion Personal information References
Longer wavelengths of light improve the growth, intake and feed efficiency of individually reared juvenile pikeperchSander lucioperca(L.)
2009
We tested the effects of monochromatic light on the specific growth rate (SGR), feed intake and feed efficiency (FE) of juvenile pikeperch, Sander lucioperca (L.). Pikeperch were reared individually for 42 days in aquaria covered with blue, green, yellow or red gelatin filters or white paper (control; n=5). Linear regression analysis indicated a significant positive effect of longer wavelengths of light on the condition factor (CF), FE and SGR. The final weight, SGR and CF were significantly higher in fish reared under red than under white light, and FE was better under green, yellow and red light than under white light (Dunnett's post hoc test, P<0.05) while blue was comparable to white li…
Assortment, but not knowledge of assortment, affects cooperation and individual success in human groups
2017
The success or failure of human collective action often depends on the cooperation tendencies of individuals in groups, and on the information that individuals have about each other's cooperativeness. However, it is unclear whether these two factors have an interactive effect on cooperation dynamics. Using a decision-making experiment, we confirm that groups comprising individuals with higher cooperation tendencies cooperate at a higher level than groups comprising individuals with low cooperation tendencies. Moreover, assorting individuals with similar cooperation tendency together affected behaviour so that the most cooperative individuals tended to cooperate more and the least cooperativ…
Data for: Financial and Fiscal Shocks in the Great Recession and Recovery of the Spanish Economy
2021
Data for paper Financial and Fiscal Shocks in the Great Recession and Recovery of the Spanish Economy THIS DATASET IS ARCHIVED AT DANS/EASY, BUT NOT ACCESSIBLE HERE. TO VIEW A LIST OF FILES AND ACCESS THE FILES IN THIS DATASET CLICK ON THE DOI-LINK ABOVE
PATIENTS' KNOWLEDGE AND AWARENESS OF RADIATION DOSE AND RISKS FROM CT: DO PATIENTS NEED A PERSONALIZED COMMUNICATION OF DOSE BILL?
2015
Aims and objectives Methods and materials Results Conclusion Personal information References
MRI DEFECOGRAPHY: TECHNIQUE, INDICATIONS AND CLINICAL FINDINGS NOT ONLY IN OBSTRUCTED DEFECATION SYNDROME
2016
Learning objectives Background Findings and procedure details Conclusion Personal information References