Littérature scientifique sur le sujet « Binocular observations »
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Articles de revues sur le sujet "Binocular observations"
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Zhang, Bin, Kazuki Matsuura, Takafumi Mori, Janice M. Wensveen, Ronald S. Harwerth, Earl L. Smith et Yuzo Chino. « Binocular Deficits Associated With Early Alternating Monocular Defocus. II. Neurophysiological Observations ». Journal of Neurophysiology 90, no 5 (novembre 2003) : 3012–23. http://dx.doi.org/10.1152/jn.00975.2002.
Texte intégralRésumé :
Experiencing binocularly conflicting signals early in life dramatically alters the binocular responses of cortical neurons. Because visual cortex is highly plastic during a critical period of development, cortical deficits resulting from early abnormal visual experience often mirror the nature of interocular decorrelation of neural signals from the two eyes. In the preceding paper, we demonstrated that monkeys that experienced early alternating monocular defocus (–1.5, –3.0, or –6.0 D) show deficits in stereopsis that generally reflected the magnitude of imposed monocular defocus. Because these results indicated that alternating monocular defocus affected the higher spatial frequency components of visual scenes more severely, we employed microelectrode recording methods to investigate whether V1 neurons in these lens-reared monkeys exhibited spatial-frequency-dependent alterations in their binocular response properties. We found that a neuron's sensitivity to interocular spatial phase disparity was reduced in the treated monkeys and that this reduction was generally more severe for units tuned to higher spatial frequencies. In the majority of the affected units, the disparity-sensitivity loss was associated with interocular differences in monocular receptive field properties. The present results suggest that the behavioral deficits in stereopsis produced by abnormal visual experience reflect at least in part the constraints imposed by alterations at the earliest stages of binocular cortical processing and support the hypothesis that the local disparity processing mechanisms in primates are spatially tuned and can be independently compromised by early abnormal visual experience.
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Wensveen, Janice M., Ronald S. Harwerth et Earl L. Smith. « Binocular Deficits Associated With Early Alternating Monocular Defocus. I. Behavioral Observations ». Journal of Neurophysiology 90, no 5 (novembre 2003) : 3001–11. http://dx.doi.org/10.1152/jn.00976.2002.
Texte intégralRésumé :
To study the binocular vision deficits associated with anisometropia, monkeys were reared with alternating monocular defocus, which allowed monocular mechanisms to develop normally while binocular mechanisms were selectively compromised. A defocusing contact lens of –1.5 D, –3 D, or –6 D was worn on alternate eyes on successive days ( n = 3 per lens power) from 3 wk to 9 mo of age. The control subjects were two normally reared monkeys and two human observers. Functional binocular vision was assessed through behavioral measurements of stereoscopic depth discrimination thresholds as a function of spatial frequency. To characterize the extent of the deficits in disparity processing at a given spatial frequency, the contrast required to support stereopsis was determined for a range of disparities that exceeded the subjects' measured stereoacuity. The lens-reared monkeys showed spatial-frequency-selective deficits in stereopsis that depended on the magnitude of the simulated anisometropia experienced during the rearing period. For a given spatial frequency, the treated monkeys generally required higher than normal contrasts to support stereopsis even for large disparities. Moreover, a given increase in contrast produced smaller than normal improvements in stereo discrimination in our treated subjects, which suggests that in addition to deficits in contrast sensitivity, disparity-sensitive mechanisms exhibited low contrast gains. The spatial-frequency selective nature of the binocular deficits produced by the imposed anisometropia indicate that disparity processing mechanisms are normally spatial-frequency selective and that mechanisms tuned to different spatial frequencies can be differentially affected by abnormal binocular visual experience.
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Testa, V., R. P. Mignani, N. Rea, M. Marelli, D. Salvetti, A. A. Breeveld, F. Cusano et R. Carini. « Large Binocular Telescope observations of PSR J2043+2740* ». Monthly Notices of the Royal Astronomical Society 473, no 2 (27 septembre 2017) : 2000–2003. http://dx.doi.org/10.1093/mnras/stx2512.
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Read, Jenny C. A., et Bruce G. Cumming. « Testing Quantitative Models of Binocular Disparity Selectivity in Primary Visual Cortex ». Journal of Neurophysiology 90, no 5 (novembre 2003) : 2795–817. http://dx.doi.org/10.1152/jn.01110.2002.
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Disparity-selective neurons in striate cortex (V1) probably implement the initial processing that supports binocular vision. Recently, much progress has been made in understanding the computations that these neurons perform on retinal inputs. The binocular energy model has been highly successful in providing a simple theory of these computations. A key feature of the energy model is that it is linear until after inputs from the two eyes are combined. Recently, however, a modified version of the energy model, incorporating threshold nonlinearities before binocular combination, has been proposed to account for the weaker disparity tuning observed with anticorrelated stimuli. In this study, we present new data needed for a critical assessment of these two models. We compare two key predictions of the models with responses of disparity-selective neurons recorded from V1 of awake fixating monkeys. We find that the original energy model, and a family of generalizations retaining linear binocular combination, are quantitatively inconsistent with the response of V1 neurons. In contrast, the modified version incorporating threshold nonlinearities can explain both sets of observations. We conclude that the energy model can be reconciled with experimental observations by adding a threshold before binocular combination. This gives us the clearest picture yet of the computation being carried out by disparity-selective V1 neurons.
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de Kleer, Katherine, Michael Skrutskie, Jarron Leisenring, Ashley G. Davies, Al Conrad, Imke de Pater, Aaron Resnick et al. « Resolving Io’s Volcanoes from a Mutual Event Observation at the Large Binocular Telescope ». Planetary Science Journal 2, no 6 (12 novembre 2021) : 227. http://dx.doi.org/10.3847/psj/ac28fe.
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Abstract Unraveling the geological processes ongoing at Io’s numerous sites of active volcanism requires high spatial resolution to, for example, measure the areal coverage of lava flows or identify the presence of multiple emitting regions within a single volcanic center. In de Kleer et al. (2017) we described observations with the Large Binocular Telescope during an occultation of Io by Europa at ∼6:17 UT on 2015 March 8 and presented a map of the temperature distribution within Loki Patera derived from these data. Here we present emission maps of three other volcanic centers derived from the same observation: Pillan Patera, Kurdalagon Patera, and the vicinity of Ulgen Patera/PV59/N Lerna Regio. The emission is localized by the light curves and resolved into multiple distinct emitting regions in two of the cases. Both Pillan and Kurdalagon Paterae had undergone eruptions in the months prior to our observations, and the location and intensity of the emission are interpreted in the context of the temporal evolution of these eruptions observed from other facilities. The emission from Kurdalagon Patera is resolved into two distinct emitting regions separated by only a few degrees in latitude that were unresolved by Keck observations from the same month.
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Ono, Hiroshi, Nicholas J. Wade et Linda Lillakas. « Binocular Vision : Defining the Historical Directions ». Perception 38, no 4 (1 janvier 2009) : 492–507. http://dx.doi.org/10.1068/p6130.
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Ever since Kepler described the image-forming properties of the eye (400 years ago) there has been a widespread belief, which remains to this day, that an object seen with one eye is always seen where it is. Predictions made by Ptolemy in the first century, Alhazen in the eleventh, and Wells in the eighteenth, and supported by Towne, Hering, and LeConte in the nineteenth century, however, are contrary to this claimed veridicality. We discuss how among eighteenth-and nineteenth-century British researchers, particularly Porterfield, Brewster, and Wheatstone, the erroneous idea continued and also why observations made by Wells were neither understood nor appreciated. Finally, we discuss recent data, obtained with a new method, that further support Wells's predictions and which show that a distinction between headcentric and relative direction tasks is needed to appreciate the predictions.
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Freeman, Alan W. « Multistage Model for Binocular Rivalry ». Journal of Neurophysiology 94, no 6 (décembre 2005) : 4412–20. http://dx.doi.org/10.1152/jn.00557.2005.
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Binocular rivalry is the alternating perception that occurs when incompatible stimuli are presented to the two eyes: one monocular stimulus dominates vision and then the other stimulus dominates, with a perceptual switch occurring every few seconds. There is a need for a binocular rivalry model that accounts for both well-established results on the timing of dominance intervals and for more recent evidence on the distributed neural processing of rivalry. The model for binocular rivalry developed here consists of four parallel visual channels, two driven by the left eye and two by the right. Each channel consists of several consecutive processing stages representing successively higher cortical levels, with mutual inhibition between the channels at each stage. All stages are architecturally identical. With n the number of stages, the model is implemented as 4 n nonlinear differential equations using a total of eight parameters. Despite the simplicity of its architecture, the model accounts for a variety of experimental observations: 1) the increasing depth of rivalry at higher cortical areas, as shown in electrophysiological, imaging, and psychophysical experiments; 2) the unimodal probability density of dominance durations, where the mode is less than the mean; 3) the lack of correlation between successive dominance durations; 4) the effect of interocular stimulus differences on dominance duration; and 5) eye suppression, as opposed to feature suppression. The model is potentially applicable to issues of visual processing more general than binocular rivalry.
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Xie, Wanyi, Yiren Wang, Yingwei Xia, Zhenyu Gao et Dong Liu. « Angular Calibration of Visible and Infrared Binocular All-Sky-View Cameras Using Sun Positions ». Remote Sensing 13, no 13 (23 juin 2021) : 2455. http://dx.doi.org/10.3390/rs13132455.
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Visible and infrared binocular all-sky-view cameras can provide continuous and complementary ground-based cloud observations. Accurate angular calibration for every pixel is an essential premise to further cloud analysis and georeferencing. However, most current calibration methods mainly rely on calibration plates, which still remains difficult for simultaneously calibrating visible and infrared binocular cameras, especially with different imaging resolutions. Thus, in this study, we present a simple and convenient angular calibration method for wide field-of-view visible and infrared binocular cameras. Without any extra instruments, the proposed method only utilizes the relation between the angular information of direct sun lights and the projected sun pixel coordinates to compute the geometric imaging parameters of the two cameras. According to the obtained parameters, the pixel-view-angle for the visible and infrared all-sky images is efficiently computed via back projection. Meanwhile, the projected pixel coordinates for the incident lights at any angle can also be computed via reprojection. Experimental results show the effectiveness and accuracy of the proposed angular calibration through the error estimation of reprojection and back projection. As a novel application, we successfully achieve visible and infrared binocular image registration at the pixel level after finishing angular calibration, which not only verifies the accuracy of calibration results, but also contributes to further cloud parameter analysis under these two different imaging features. The registration results, to our knowledge, also provide a reference for the current blank in visible and infrared binocular cloud image registration.
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Ashcraft, Teresa A., Tyler McCabe, Caleb Redshaw, Rogier A. Windhorst, Rolf A. Jansen, Seth H. Cohen, Timothy Carleton et al. « Deep Large Binocular Camera r-band Observations of the GOODS-N Field ». Publications of the Astronomical Society of the Pacific 135, no 1044 (1 février 2023) : 024101. http://dx.doi.org/10.1088/1538-3873/aca1e0.
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Abstract We obtained 838 Sloan r-band images (∼28 hr) of the GOODS-North field with the Large Binocular Camera (LBC) on the Large Binocular Telescope in order to study the presence of extended, low surface brightness features in galaxies and investigate the trade-off between image depth and resolution. The individual images were sorted by effective seeing, which allowed for optimal resolution and optimal depth mosaics to be created with all images with seeing FWHM < 0.″9 and FWHM < 2.″0, respectively. Examining bright galaxies and their substructure as well as accurately deblending overlapping objects requires the optimal resolution mosaic, while detecting the faintest objects possible (to a limiting magnitude of m AB ∼ 29.2 mag) requires the optimal depth mosaic. The better surface brightness sensitivity resulting from the larger LBC pixels, compared to those of extant WFC3/UVIS and ACS/WFC cameras aboard the Hubble Space Telescope allows for unambiguous detection of both diffuse flux and very faint tidal tails. Azimuthally-averaged radial surface brightness profiles were created for the 360 brightest galaxies in each of the two mosaics. On average, these profiles showed minimal difference between the optimal resolution and optimal depth surface brightness profiles. However, ≲15% of the profiles show excess flux in the galaxy outskirts down to surface brightness levels of μ r AB ≃ 31 mag arcsec−2. This is relevant to Extragalactic Background Light (EBL) studies as diffuse light in the outer regions of galaxies are thought to be a major contribution to the EBL. While some additional diffuse light exists in the optimal depth profiles compared to the shallower, optimal resolution profiles, we find that diffuse light in galaxy outskirts is a minor contribution to the EBL overall in the r-band.
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Blais, Brian S., Mikhail Y. Frenkel, Scott R. Kuindersma, Rahmat Muhammad, Harel Z. Shouval, Leon N. Cooper et Mark F. Bear. « Recovery From Monocular Deprivation Using Binocular Deprivation ». Journal of Neurophysiology 100, no 4 (octobre 2008) : 2217–24. http://dx.doi.org/10.1152/jn.90411.2008.
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Ocular dominance (OD) plasticity is a robust paradigm for examining the functional consequences of synaptic plasticity. Previous experimental and theoretical results have shown that OD plasticity can be accounted for by known synaptic plasticity mechanisms, using the assumption that deprivation by lid suture eliminates spatial structure in the deprived channel. Here we show that in the mouse, recovery from monocular lid suture can be obtained by subsequent binocular lid suture but not by dark rearing. This poses a significant challenge to previous theoretical results. We therefore performed simulations with a natural input environment appropriate for mouse visual cortex. In contrast to previous work, we assume that lid suture causes degradation but not elimination of spatial structure, whereas dark rearing produces elimination of spatial structure. We present experimental evidence that supports this assumption, measuring responses through sutured lids in the mouse. The change in assumptions about the input environment is sufficient to account for new experimental observations, while still accounting for previous experimental results.
Thèses sur le sujet "Binocular observations"
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« Deep Imaging of Distant Galaxies Using the Large Binocular Telescope ». Doctoral diss., 2018. http://hdl.handle.net/2286/R.I.50516.
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abstract: In the past three decades with the deployment of space-based from x-rays to infrared telescopes and operation of 8-10 m class ground based telescopes, a hand-full of regions of the sky have emerged that probe the distant universe over relatively wide fields with the aim of understanding the assembly of apparently faint galaxies. To explore this new frontier, observations were made with the Large Binocular Cameras (LBCs) on the Large Binocular Telescope (LBT) of a well-studied deep field, GOODS-North, which has been observed by a wide range of telescopes from the radio to x-ray. I present a study of the trade-off between depth and resolution using a large number of LBT/LBC U-band and R-band imaging observations in the GOODS-N field. Having acquired over 30 hours of data (315 images with 5-6 minute exposures) for U-band and 27 hours for R-band (828 images with 2 minute exposures), multiple mosaics were generated, starting with images taken under the best atmospheric conditions (FWHM <0.8"). For subsequent mosaics, data with coarser seeing values were added in until the final, deepest mosaic included all images with FWHM <1.8". For each mosaic, object catalogs were made to compare the optimal-resolution, yet shallower image to the low-resolution but deeper image. For the brightest galaxies within the GOODS-N field, structure and clumpy features within the galaxies are more prominent in the optimal-resolution image compared to the deeper mosaics. I conclude that for studies of brighter galaxies and features within them, the optimal-resolution image should be used. However, to fully explore and understand the faintest objects, the deeper imaging with lower resolution are also required. For the 220 and 360 brightest galaxies in the U-band and R-band images respectively, there is only a marginal difference between the optimal-resolution and lower-resolution light-profiles and their integrated total fluxes. This helps constrain how much flux can be missed in galaxy outskirts, which is important for studies of Extragalactic Background Light. Finally, I also comment on a collection of galaxies in the field with tidal tails and streams, diffuse plumes, and bridges.Dissertation/Thesis
Doctoral Dissertation Astrophysics and Astronomy 2018
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Zhang, Yuqing. « Partially perfluorinated derivatives as powerful components for artwork restoration ». Doctoral thesis, 2022. https://hdl.handle.net/2158/1290796.
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Stone artworks and easel paintings are challenged by diverse degradations. In particularly, this thesis focuses
on two restoration issues mainly induced by liquid water or moisture, which are stone degradation and blanching
of easel paintings. From previous research, partially perfluorinated derivatives have been proved to provide
promising restoration performance on those two restoration issues, by showing good water repellency as stone
protective products and decreasing blanching in easel paintings. Inspired by those results, two families of partially
perfluorinated derivatives with hydroxyl groups are proposed and designed as stone protection and blanching
painting restoration products in this thesis. Those hydroxyl groups could give good adhesion on polar stone
substrates by hydrogen bonding. Meanwhile, hydrophobicity of the compounds can be realized by the
perfluorinated chains.
The first compounds proposed and synthesized are partially perfluorinated C-glycosides. C-glycosides are
carbon-linked analogues of naturally occurring sugars, which have high hydrophilic properties due to the polar
hydroxyl groups. In addition to the hydrophilicity and water repellency, C-glycosides themselves possess an
improved stability towards hydrolysis. Starting from the unprotected carbohydrate, the natural, renewable and
cheap D-glucose, via Lubineau reaction and followed by the convenient one-pot reductive amination reaction, the
target compound (partially perfluorinated C-glycoside) was successfully obtained. Moreover, partially
perfluorinated C-glycoside with acetyl groups as protecting groups has been successfully synthesized as a control
compound, in order to investigate if hydroxyl groups in C-glycoside can improve the restoration efficacy as
expected. Then, those new partially perfluorinated C-glycosides have been tested on stone materials as
protective products, and on blanching mock-up painting samples. The results indicated that different properties
of those C-glycosides caused by the hydroxyls, like physical states, solubility, color and interaction with stone and
painting substrates, have been influenced their behaviors as the restoration products.
The other series of compounds proposed is partially perfluorinated hydroxylated oligoamides. In order to
further improve the interaction between partially perfluorinated oligomers and polar substrates, new partially
perfluorinated hydroxylated oligoamides derived from different monomers (dimethyl L-tartrate, diethyl succinate,
diethylenetriamine or ethylenediamine) have been successfully synthesized. Those compounds have different
structures and properties, i.e. solubility, hydrophilicity, chain length, molecular weight, and etc. Moreover, in
order to understand the roles of hydroxyl group and amine in the applicative performance, new partially
perfluorinated oligamides with no hydroxyl groups, but with the unchanged amine and succinate sources were
successfully synthesized. Then, those new partially perfluorinated derivatives were tested on stone and mock-up
blanching painting samples. The results showed that their efficacy for restoration was highly influenced by the
structures and properties of the molecules.
At the end, 4 promising new partially perfluorinated derivatives for stone protection and blanching painting
restoration have been selected. Further optimization of the structures of molecules and their practical process for
the application on stone artefacts and easel paintings worth being developed in the future to go deeper on this
main cultural heritage approach.
Livres sur le sujet "Binocular observations"
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Kislyuk, V. S. Moon in the Sky… PH “Akademperiodyka”, 2009. http://dx.doi.org/10.15407/akademperiodyka.126.120.
Texte intégralRésumé :
The book “Moon in the Sky…” consists of two chapters: “The Wonderful World of Selena” and “Return to the Moon.” The first of them tells about the current state of the study of the Moon: its origin, features of rotational motion, nature and internal structure. The second section discusses the problems of further study and development of the Earth's natural satellite with the help of spacecraft and the creation of populated scientific and research-production bases on its surface. The appendices provide basic information about the Moon, a glossary of lunar terms, a chronology of lunar explorations using spacecraft, a map of the visible side of the Moon for observations with binoculars or a school telescope. The book “Moon in the Sky…” is intended for a wide range of readers.
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Real Life Observation Proof Study of S.S.S.R.D. and the Cortex Eye and Also the Dome Shaped Image : The Two Permanent Structures in the Optic Array for Binocular and Monocular Visual Perception. Choice Publishing, 2017.
Trouver le texte intégralChapitres de livres sur le sujet "Binocular observations"
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Powers, Maureen, et William P. Fisher. « Functional Binocular Vision : Toward a Person-Centered Metric ». Dans Springer Series in Measurement Science and Technology, 151–64. Cham : Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-07465-3_6.
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AbstractA research program investigating correctable issues in Functional Binocular Vision (FBV) related optometric variables to responses from a symptom survey and reading test results. The study was mounted with no explicit attention to measurement modeling. Data from this research program were retrospectively analyzed with the aims of evaluating the potential for learning from the existing observations, and for improving the study design in future iterations. Results suggest that the physical and psychological measurements of vision combine into a model of FBV that could be standardized and deployed for use in diagnosing significant numbers of untreated vision problems negatively impacting learning outcomes.
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Ropelewski, Mike, et R. W. Argyle. « The Observation of Binocular Double Stars ». Dans Observing and Measuring Visual Double Stars, 25–32. New York, NY : Springer New York, 2012. http://dx.doi.org/10.1007/978-1-4614-3945-5_3.
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Skov, M. W., et R. G. Hartnoll. « Comparative suitability of binocular observation, burrow counting and excavation for the quantification of the mangrove fiddler crab Uca annulipes (H. Milne Edwards) ». Dans Advances in Decapod Crustacean Research, 201–12. Dordrecht : Springer Netherlands, 2001. http://dx.doi.org/10.1007/978-94-017-0645-2_22.
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Brinton, Daniel A., et Charles P. Wilkinson. « History of Surgery for Retinal Detachment ». Dans Retinal Detachment. Oxford University Press, 2009. http://dx.doi.org/10.1093/oso/9780195330823.003.0005.
Texte intégralRésumé :
The evolution of the retinal reattachment operation is one of the most remarkable chapters in the history of ophthalmology. Gonin’s operation for repair of the detached retina ranks with Daviel’s cataract extraction, von Graefe’s peripheral iridectomy, and Machemer’s vitrectomy as one of history’s most important surgical treatments for blinding eye diseases. The entity of retinal detachment was recognized early in the eighteenth century by de Saint-Yves, who reported the gross pathologic examination of an eye with a detached retina. The first clinical description did not appear until almost a century later, in 1817, when Beer detected a retinal detachment without the benefit of an ophthalmoscope. Von Helmholtz’s invention of the direct ophthalmoscope in 1851 was a giant step forward in diagnostic technique, and a rapid succession of ophthalmoscopic observations of retinal detachments soon followed. In the same year, Coccius reported the ophthalmoscopic detection of breaks in the detached retina. Von Graefe theorized in 1858 that retinal detachment was caused by a serous effusion from the choroid into the subretinal space. When he observed a retinal break, he assumed that it was secondary to the detachment and represented the eye’s attempt to cure itself. Supposing that the development of a break would allow the subretinal fluid to pass from the subretinal space into the vitreous cavity, he attempted unsuccessfully to treat detachments with deliberate incision of the retina. Girard-Teulon invented the reflecting binocular indirect ophthalmoscope in 1861. This potentially important contribution was generally overlooked by the profession, and more than 80 years transpired before Schepens developed the selfilluminating binocular indirect ophthalmoscope. In 1869 Iwanoff described the entity of posterior vitreous detachment, which is now recognized as a prerequisite to the development of most retinal detachments. The following year de Wecker suggested that retinal breaks cause detachment due to the resultant passage of vitreous fluid through the break into the subretinal space. Unfortunately, his accurate interpretation was not generally accepted. In 1882 Leber reported his observation of retinal breaks in 14 of 27 retinal detachments, and he correctly inferred the role of vitreous traction in the pathogenesis of breaks. Unfortunately, he later altered this opinion.
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« Vision binoculaire et observation stéréoscopique ». Dans Précis de télédétection, 133–62. Presses de l'Université du Québec, 2007. http://dx.doi.org/10.2307/j.ctv18ph8f6.12.
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Ducruix, A., et R. Giegé. « Methods of Crystallization ». Dans Crystallization of Nucleic Acids and Proteins. Oxford University Press, 1999. http://dx.doi.org/10.1093/oso/9780199636792.003.0009.
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There are many methods to crystallize biological macromolecules (for reviews see refs 1-3), all of which aim at bringing the solution of macromolecules to a supersaturation state (see Chapters 10 and 11). Although vapour phase equilibrium and dialysis techniques are the two most favoured by crystallographers and biochemists, batch and interface diffusion methods will also be described. Many chemical and physical parameters influence nucleation and crystal growth of macromolecules (see Chapter 1, Table 1). Nucleation and crystal growth will in addition be affected by the method used. Thus it may be wise to try different methods, keeping in mind that protocols should be adapted (see Chapter 4). As solubility is dependent on temperature (it could increase or decrease depending on the protein), it is strongly recommended to work at constant temperature (unless temperature variation is part of the experiment), using commercially thermoregulated incubators. Refrigerators can be used, but if the door is often open, temperature will vary, impeding reproducibility. Also, vibrations due to the refrigerating compressor can interfere with crystal growth. This drawback can be overcome by dissociating the refrigerator from the compressor. In this chapter, crystallization will be described and correlated with solubility diagrams as described in Chapter 10. Observation is an important step during a crystallization experiment. If you have a large number of samples to examine, then this will be time-consuming, and a zoom lens would be an asset. The use of a binocular generally means the presence of a lamp; use of a cold lamp avoids warming the crystals (which could dissolve them). If crystals are made at 4°C and observation is made at room temperature, observation time should be minimized. Preparation of the solutions of all chemicals used for the crystallization of biological macromolecules should follow some common rules: • when possible, use a hood (such as laminar flux hood) to avoid dust • all chemicals must be of purest chemical grade (ACS grade) • stock solutions are prepared as concentrated as possible with double distilled water. Solubility of most chemicals are given in Merck Index. Filter solutions with 0.22 μm minifilter.
Actes de conférences sur le sujet "Binocular observations"
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Cogan, Alexander I. « Toward a general model of binocular Interaction ». Dans OSA Annual Meeting. Washington, D.C. : Optica Publishing Group, 1986. http://dx.doi.org/10.1364/oam.1986.mi3.
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A recent model1 of binocular interaction in human vision was tested at the differential luminance threshold; it was also used to fit the data of Birch2 on suprathreshold contrast matching. The quantitative model was quite successful in predicting the relations among monoptic, binoptic, and dichoptic effects, both at threshold and for the suprathreshold task. The threshold experiment was similar to that of Cohn and Lasley,3 and their observations were replicated. It will be shown, however, that these observations do not indicate the operation of two independent binocular channels, as proposed by Cohn and Lasley.3 On the present model1 all binocular stimuli, of whatever interocular polarity, are processed in the same bilateral either-eye channel, where excitatory summation is reduced by reciprocal inhibition. In addition, same-polarity (binoptic) stimuli evoke a fused binocular response that is purely excitatory. The model offers a unified qualitative explanation for diverse binocular phenomena, including the Julesz-Tyler neurontropy.4
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Zhang, Yu, Xiping Xu, Yaowen Lv et Kailin Zhang. « Visual odometry based on binocular catadioptric panoramic camera ». Dans Conference on Novel Technologies and Instruments for Astronomical Multi-Band Observations, sous la direction de Suijian Xue et Yongtian Zhu. SPIE, 2021. http://dx.doi.org/10.1117/12.2606363.
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Spalding, Eckhart, Phil Hinz, Steve Ertel, Jordan Stone et Erin Maier. « Towards controlled Fizeau observations with the Large Binocular Telescope ». Dans Optical and Infrared Interferometry and Imaging VI, sous la direction de Antoine Mérand, Michelle J. Creech-Eakman et Peter G. Tuthill. SPIE, 2018. http://dx.doi.org/10.1117/12.2315498.
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Cogan, Alexander I., Maureen Clarke et Andrew Rossi. « Interocular phase : its effect on binocular summation ». Dans OSA Annual Meeting. Washington, D.C. : Optica Publishing Group, 1987. http://dx.doi.org/10.1364/oam.1987.fh3.
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Assuming that the internal response to a brief change of luminance is biphasic,1 it has been proposed2 that responses to binocular stimuli must be interocularly in phase to produce a hypothetical fused effect represented psychophysically as binocular summation (e.g., at threshold). Binocular summation has been demonstrated3 for stimuli that were both spatially and temporally in 0 or 180° phase. These observations are in agreement with the model.2 To test it further, we measured differential luminance thresholds for binocular stimuli of like and opposite polarity as a function of interocular delay (SOA). Pulse duration was a parameter between 5 and 150 ms. With no delay, thresholds were lower for like than for opposite polarity stimuli: the usual finding. The relationship was reversed at a critical delay, near SOA = 50 ms. This effect was at maximum for pulses of 50-ms duration, which suggests that (1) both on and off parts of a pulse contribute to the net response and (2) there is a limit (a temporal window) of phase dependent binocular interaction.
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Matsuki, Hitomi, Shohei Mori, Sei Ikeda, Fumihisa Shibata, Asako Kimura et Hideyuki Tamura. « Considerations on binocular mismatching in observation-based diminished reality ». Dans 2016 IEEE Symposium on 3D User Interfaces (3DUI). IEEE, 2016. http://dx.doi.org/10.1109/3dui.2016.7460070.
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Yang, Chen, He Xu, Xin Li, Haihang Wang et Fengshu Yu. « Underwater Flexible Manipulator Double-Loop Feedback Control Based on Built-in Binocular Vision and Displacement Sensor ». Dans BATH/ASME 2020 Symposium on Fluid Power and Motion Control. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/fpmc2020-2730.
Texte intégralRésumé :
Abstract A real-time and effective double-loop feedback control system for underwater flexible manipulators is raised in this paper. The research object is a kind of underwater flexible manipulator driven by McKibben water hydraulic artificial muscle (WHAM) that can grasp, swallow, and disgorge target objects in its interior space. To make up for the lack of flexibility, an underwater flexible manipulator collaborative working strategy is proposed. A more flexible and smaller flexible manipulator is placed inside the flexible manipulator to assist it in performing difficult underwater works. The control system feeds back the position of internal objects through a built-in binocular camera and the working state of the manipulator through displacement sensors. The control system setups including underwater flexible manipulator subsystem, hydraulic drive subsystem, PLC control subsystem, displacement sensor subsystem, built-in binocular vision subsystem, and upper computer subsystem is built. PYTHON-based built-in binocular vision software and C++-based underwater flexible manipulator control software are also developed to facilitate observation and recording. The underwater flexible manipulator collaborative experiment is designed to verify the performance of the control system and the control algorithm.
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Shioiri, Satoshi, Tadashi Koshige et Souichi Kubo. « Optimum lead time of luminance cue for facilitating stereoscopic perception time ». Dans OSA Annual Meeting. Washington, D.C. : Optica Publishing Group, 1993. http://dx.doi.org/10.1364/oam.1993.wrr.4.
Texte intégralRésumé :
We investigated the effect of preceding luminance depth cues on stereopsis perception time. The stimulus was a random-dot stereogram which contained two horizontal bands defined by binocular disparity: the dots inside of one of the bands had crossed disparity (the band was closer than the background) and those inside of the other were uncorrelated. The dots in the disparity bands were lighter than those in the background so that the both bands appeared to be closer by monocular observation. Observer’s task was to report which band appeared to be closer. The method of constant stimuli was used to determine the stereopsis perception time as the stimulus presentation duration which gave 75 (varied between 0 and 1000 msec). The results show that the perception time is the shortest when the luminance cue lead time is about 200 msec. Since little effect of the lead time was found when dots inside of the disparity bars were darker than those in background, it is suggested that the optimum lead time of luminance cue is a reflection of the dynamic interaction between monocular and binocular depth cues rather than that of attention.
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Awano, Yumi. « Effect of the luminous of the peripheral visual field on the binocular vision : aspects of three-dimensional seeing on the different color stimulus observation with stereoscope on CRT display ». Dans 9th Congress of the International Color Association, sous la direction de Robert Chung et Allan Rodrigues. SPIE, 2002. http://dx.doi.org/10.1117/12.464535.
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