Search results for " display"
showing 10 items of 225 documents
Comparative assessment of spatial perception in augmented reality depending on the consistency of depth cues
2021
Discrepancies between depth cues (accommodation and vergence) is one of the major issues caused in a stereoscopic augmented reality at close viewing distances. It adversely affects not only user comfort but also spatial judgements. Images with consonant cues at different distances have become available due to the implementation of multifocal architecture in the head-mounted displays, although its effect on spatial perception has remained unknown. In this psychophysical study, we investigated the effects of consonant and conflicting depth cues on perceptual distance matching in the stereoscopic environment of augmented reality using a head-mounted display that was driven in two modes: multif…
Optical See-Through Head-Mounted Displays With Short Focal Distance: Conditions for Mitigating Parallax-Related Registration Error
2020
Optical see-through (OST) augmented reality head-mounted displays are quickly emerging as a key asset in several application fields but their ability to profitably assist high precision activities in the peripersonal space is still sub-optimal due to the calibration procedure required to properly model the user's viewpoint through the see-through display. In this work, we demonstrate the beneficial impact, on the parallax-related AR misregistration, of the use of optical see-through displays whose optical engines collimate the computer-generated image at a depth close to the fixation point of the user in the peripersonal space. To estimate the projection parameters of the OST display for a …
Pheromonal emission during the mating behavior ofEurycotis floridana (Walker) (Dictyoptera: Blattidae)
1996
The sexual behavior of males and females ofEurycotis floridana was investigated and the various associated behavioral sequences are described. Olfactometer data proved that the male produces a volatile sex pheromone attractive at a distance to conspecific females. The male initiates courtship behavior by exposing the glandular areas on the anterior parts of abdominal tergites 2, 7, and 8. This male calling behavior was observed throughout the day. The males can mate when 8 days old, whereas virgin females are sexually receptive 18 days after becoming adults. Once attracted near the male, the female opens her genital atrium and climbs on the back of the male, where she feeds on the glandular…
Testing the assumptions of conditional handicap theory: costs and condition dependence of a sexually selected trait
2000
Conditional handicap models of sexual selection predict that sexual traits are reliable signals of male quality because they are (a) condition dependent and (b) costly to produce or maintain. In this study, my objective was to experimentally investigate whether the drumming of male Hygrolycosa rubrofasciata wolf spiders is a condition-dependent costly trait. Males court females by drumming dry leaves with their abdomen and females preferentially mate with males drumming at higher rates. I manipulated male phenotypic condition and drumming rate simultaneously by keeping males on three different food rations and either introducing or not introducing them to a female. Food ration treatment aff…
In vivo studies of altered expression patterns of p53 and proliferative control genes in chronic vitamin A deficiency and hypervitaminosis
2003
Several clinical trials have revealed that individuals who were given beta-carotene and vitamin A did not have a reduced risk of cancer compared to those given placebo; rather, vitamin A could actually have caused an adverse effect in the lungs of smokers [Omenn, G.S., Goodman, G.E., Thornquist, M.D., Balmes, J., Cullen, M.R., Glass, A., Keogh, J.P., Meyskens, F.L., Valanis, B., Williams, J.H., Barnhart, S. & Hammar, S. N. Engl. J. Med (1996) 334, 1150-1155; Hennekens, C.H., Buring, J.E., Manson, J.E., Stampfer, M., Rosner, B., Cook, N.R., Belanger, C., LaMotte, F., Gaziano, J.M., Ridker, P.M., Willet, W. & Peto, R. (1996) N. Engl. J. Med. 334, 1145-1149]. Using differential display techniq…
Identification of a gene overexpressed in aphids reared under short photoperiod.
2003
Most aphids develop a cyclic parthenogenesis life-cycle. After several generations of viviparously produced parthenogenetic females, follows a single annual generation of sexual individuals, usually in autumn, that mate and lay the sexual eggs. Shortening of photoperiod at the end of the summer (together with temperature) is a key factor inducing the sexual response. Currently no genes involved in the cascade of events that lead to the appearance of sexual forms have been reported. After a Differential Display RT-PCR survey performed on Acyrthosiphon pisum aphids, we identified a gene that is overexpressed in aphids reared under short photoperiod conditions that induce sexuality in this spe…
Role of ambient light in the detection of contrast elements in digital dental radiography.
2018
Objective This study aimed to evaluate the effect of different ambient light levels on observer detection of small contrast differences in a contrast phantom by using a high-end liquid crystal display (LCD) monitor. Study Design An aluminum step wedge was converted into a contrast phantom by the addition of bore holes. Radiographic images of the contrast elements were presented to 20 observers. Images were displayed in random order under different ambient light levels (0, 50, 200, and 500 lux) twice, and the observers had to determine if contrast elements were visible. Sensitivity and specificity were determined to calculate areas under receiver operating characteristic curves and Friedmann…
PCR-Amplified cDNA Probes for Verification of Differentially Expressed Genes
1997
Differential display has proven to be a powerful technique for the detection and isolation of differentially expressed genes. By generating reproducible cDNA expression patterns, it is possible to compare gene expression by two or more cell types, developmental stages or tissues and to isolate as yet unknown differentially expressed genes. A sensitive method is necessary to verify the differential expression of the isolated cDNAs. Here we describe the use of adaptor-ligated, PCR-amplified total cDNA of the two cell types compared as a probe for Southern hybridizations with the isolated cDNAs.
Mid-region parathyroid hormone-related protein (PTHrP) and gene expression of MDA-MB231 breast cancer cells.
2007
Abstract We have previously shown that PTHrP(38–94) amide restrains growth and invasion in vitro, causes striking toxicity and accelerates death of some breast cancer cell lines, the most responsive being MDA-MB231, for which tumorigenesis was also attenuated in vivo. We have also demonstrated that mid-region PTHrP gains access to the nuclear compartment of these cells and displays DNA-binding properties in vitro by recognizing targets in both cellular chromatin and isolated oligonucleotides. Here, we examined whether PTHrP(38–94) amide was able to modulate gene expression of MDA-MB231 cells, employing a combination of conventional, differential display and semi-quantitative multiplex PCR t…
Induction of tcI 7 , a gene encoding a β-subunit of proteasome, in tobacco plants treated with elicitins, salicylic acid or hydrogen peroxide 1
2000
We previously isolated, by differential display and 5′ RACE (rapid amplification of cDNA ends), cDNAs corresponding to genes activated following cryptogein treatment of tobacco cell suspensions, among them tcI 7 (tcI for obacco ryptogein nduced), a gene encoding a β-subunit of proteasome. Here, we report that tcI 7 was up-regulated in tobacco plants treated with elicitins (cryptogein and parasiticein) that have been shown to induce a systemic acquired resistance (SAR). Moreover, subsequent inoculation of tobacco with the pathogen Phytophthora parasitica var. nicotianae (Ppn) was shown to induce an additional activation of tcI 7 in tobacco plants pretreated with cryptogein. We also showed an…