Search results for "Lens"
showing 10 items of 948 documents
Euclid preparation. XII. Optimizing the photometric sample of the Euclid survey for galaxy clustering and galaxy-galaxy lensing analyses
2021
Pocino, A., et al. (Euclid Collaboration)
“Thanks for Watching.” The Effectiveness of YouTube vlogendorsements
2019
This study examines the effectiveness of brand endorsements in vlogs (video blogs) by assessing the role of audience participation, parasocial relationship, and valence toward vlog endorsements on the perceived credibility of the vlogger and brand attitudes. Four experimental conditions were created on Qualtrics based on a YouTube vlog where the endorser reviewed a few products. The data were collected using Mturk and analyzed with 203 usable responses. The findings indicate that audience participation in the vlog enhances para-social relationship with the vlogger, thus further fostering the vlogger's perceived credibility as an endorser. Additionally, the valence of the audience's attitude…
Generation of programmable 3D optical vortex structures through devil’s vortex-lens arrays
2013
Different spatial distributions of optical vortices have been generated and characterized by implementing arrays of devil's vortex lenses in a reconfigurable spatial light modulator. A simple design procedure assigns the preferred position and topological charge value to each vortex in the structure, tuning the desired angular momentum. Distributions with charges and momenta of the opposite sign have been experimentally demonstrated. The angular velocity exhibited by the phase distribution around the focal plane has been visualized, showing an excellent agreement with the simulations. The practical limits of the method, with interest for applications involving particle transfer and manipula…
Ambivalent emotional experiences of everyday visual and musical objects.
2019
Art brings rich, pleasurable experiences to our daily lives. However, many theories of art and aesthetics focus on specific strong experiences—in the contexts of museums, galleries, and concert halls and the aesthetic perception of canonized arts—disregarding the impact of daily experiences. Furthermore, pleasure is often treated as a simplistic concept of merely positive affective character, yet recent psychological research has revealed the experience of pleasure is far more complicated. This study explored the nature of pleasure evoked by everyday aesthetic objects. A mixture of statistical and qualitative methods was applied in the analysis of the data collected through a semi-structure…
Behavioural thresholds of blue tit colour vision and the effect of background chromatic complexity
2020
Vision is a vital attribute to foraging, navigation, mate selection and social signalling in animals, which often have a very different colour perception in comparison to humans. For understanding how animal colour perception works, vision models provide the smallest colour difference that animals of a given species are assumed to detect. To determine the just-noticeable-difference, or JND, vision models use Weber fractions that set discrimination thresholds of a stimulus compared to its background. However, although vision models are widely used, they rely on assumptions of Weber fractions since the exact fractions are unknown for most species. Here, we test; i) which Weber fractions in lo…
Emotional expression in music: contribution, linearity, and additivity of primary musical cues
2013
The aim of this study is to manipulate musical cues systematically to determine the aspects of music that contribute to emotional expression, and whether these cues operate in additive or interactive fashion, and whether the cue levels can be characterized as linear or non-linear. An optimized factorial design was used with six primary musical cues (mode, tempo, dynamics, articulation, timbre, and register) across four different music examples. Listeners rated 200 musical examples according to four perceived emotional characters (happy, sad, peaceful, and scary). The results exhibited robust effects for all cues and the ranked importance of these was established by multiple regression. The …
Agreement between 2 swept-source OCT biometers and a Scheimpflug partial coherence interferometer
2020
PURPOSE To evaluate the agreement between different parameters obtained with 2 swept-source optical coherence tomography (SS-OCT)-based biometers and 1 Scheimpflug camera with partial coherence interferometry (PCI). SETTING Single center, Oftalvist, Alicante, Spain. DESIGN Prospective case series. METHODS Biometry was performed in 49 eyes using 3 optical biometers: ANTERION SS-OCT, IOLMaster 700 SS-OCT, and Pentacam AXL PCI. Keratometry (K), J0 and J45 vectors, anterior chamber depth (ACD), central corneal thickness (CCT), white-to-white (WTW), lens thickness (LT), and axial length (AL) were measured with each device. Bland-Altman analysis was applied. RESULTS This study comprises 49 eyes o…
Determining postoperative anterior chamber depth
2003
Abstract Purpose: To compare measured and calculated postoperative anterior chamber depths (ACDs). Setting: Department of Ophthalmology and Institute of Medical Physics, University of Vienna, Vienna, Austria, and Department of Ophthalmology, University of Mainz, Mainz, Germany. Methods: The postoperative ACD was measured in 189 pseudophakic eyes using a laboratory prototype of partial coherence interferometry (PCI). In 6 intraocular lens (IOL) groups, the mean ACD was calculated by ray tracing based on the best-known A-constants of the SRK formulas. In addition, for each IOL type, each measured ACD was compared with a value calculated using the individual spherical equivalent of the postope…
Comparison of biometric measurements using partial coherence interferometry and applanation ultrasound
2003
Abstract Purpose To compare and contrast axial length (AL) measurements assessed by ultrasound biometry and optical biometry. Setting Department of Ophthalmology, Johannes Gutenberg-University, Mainz, Germany. Methods Optical biometry and ultrasound biometry were performed in 360 eyes to measure AL. Results In eyes with a clear-appearing crystalline lens, there was a statistically significant median difference in AL measurements between the 2 methods in eyes with a normal or long length. In eyes with cataract, there was a statistically significant median difference in AL measurements in eyes with a normal or short length. In these cases, optical biometry produced larger readings than ultras…
Flegmasia cerulea dolens en paciente con carcinoma testicular
2006
Describimos un caso de flegmasia cerulea dolens secundaria a una trombosis venosa profunda por compresión de la vena cava inferior, en un varón de 31 años con un tumor germinal. Necesitó un tratamiento urgente con agentes fibrinolíticos, heparina intravenosa y quimioterapia. Con el tratamiento obtuvo una respuesta completa tumoral y una completa revascularización de la vena cava y vena femoral derecha.