Perceptual motion standstill in rapidly moving chromatic displays

In motion standstill, a quickly moving object appears to stand still, and its details are clearly visible. It is proposed that motion standstill can occur when the spatiotemporal resolution of the shape and color systems exceeds that of the motion systems. For moving red-green gratings, the first- and second-order motion systems fail when the grating is isoluminant. The third-order motion system fails when the green/red saturation ratio produces isosalience (equal distinctiveness of red and green). When a variety of high-contrast red-green gratings, with different spatial frequencies and speeds, were made isoluminant and isosalient, the perception of motion standstill was so complete that motion direction judgments were at chance levels. Speed ratings also indicated that, within a narrow range of luminance contrasts and green/red saturation ratios, moving stimuli were perceived as absolutely motionless. The results provide further evidence that isoluminant color motion is perceived only by the third-order motion system, and they have profound implications for the nature of shape and color perception.

Circuitry for color coding in the primate retina.

Human color vision starts with the signals from three cone photoreceptor types, maximally sensitive to long (L-cone), middle (M-cone), and short (S-cone) wavelengths. Within the retina these signals combine in an antagonistic way to form red-green and blue-yellow spectral opponent pathways. In the classical model this antagonism is thought to arise from the convergence of cone type-specific excitatory and inhibitory inputs to retinal ganglion cells. The circuitry for spectral opponency is now being investigated using an in vitro preparation of the macaque monkey retina. Intracellular recording and staining has shown that blue-ON/yellow-OFF opponent responses arise from a distinctive bistratified ganglion cell type. Surprisingly, this cone opponency appears to arise by dual excitatory cone bipolar cell inputs: an ON bipolar cell that contacts only S-cones and an OFF bipolar cell that contacts L- and M-cones. Red-green spectral opponency has long been linked to the midget ganglion cells, but an underlying mechanism remains unclear. For example, receptive field mapping argues for segregation of L-and M-cone signals to the midget cell center and surround, but horizontal cell interneurons, believed to generate the inhibitory surround, lack opponency and cannot contribute selective L- or M-cone input to the midget cell surround. The solution to this color puzzle no doubt lies in the great diversity of cell types in the primate retina that still await discovery and analysis.

Characterization of a new murine retinal cell line (MU-PH1) with glial, progenitor and photoreceptor characteristics

Unlike fish and amphibians, mammals do not regenerate retinal neurons throughout life. However, neurogenic potential may be conserved in adult mammal retina and it is necessary to identify the factors that regulate retinal progenitor cells (RPC) proliferative capacity to scope their therapeutic potential. Müller cells can be progenitors for retinal neuronal cells and can play an essential role in the restoration of visual function after retinal injury. Some members of the Toll-like receptor (TLR) family, TLR2, TLR3 and TLR4, are related to progenitor cells proliferation. Müller cells are important in retinal regeneration and stable cell lines are useful for the study of retinal stem cell biology. Our purpose was to obtain a Müller-derived cell line with progenitor characteristics and potential interest in regeneration processes. We obtained and characterized a murine Müller-derived cell line (MU-PH1), which proliferates indefinitely in vitro. Our results show that (i) MU-PH1 cells expresses the Müller cell markers Vimentin, S-100, glutamine synthetase and the progenitor and stem cell markers Nestin, Abcg2, Ascl1, α-tubulin and β-III-tubulin, whereas lacks the expression of CRALBP, GFAP, Chx10, Pax6 and Notch1 markers; (ii) MU-PH1 cell line stably express the photoreceptor markers recoverin, transducin, rhodopsin, blue and red/green opsins and also melanopsin; (iii) the presence of opsins was confirmed by the recording of intracellular free calcium levels during light stimulation; (iv) MU-PH1 cell line also expresses the melatonin MT1 and MT2 receptors; (v) MU-PH1 cells express TLR1, 2, 4 and 6 mRNA; (vi) MU-PH1 express TLR2 at cell surface level; (vii) Candida albicans increases TLR2 and TLR6 mRNA expression; (viii) C. albicans or TLR selective agonists (Pam(3)CysSK(4), LPS) did not elicit morphological changes nor TNF-α secretion; (ix) C. albicans and Pam(3)CysSK(4) augmented MU-PH1 neurospheres formation in a statistically significant manner. Our results indicate that MU-PH1 cell line could be of great interest both as a photoreceptor model and in retinal regeneration approaches and that TLR2 may also play a role in retinal cell proliferation.

Visual function alterations in essential tremor: A case report

Our purpose is to report alterations in contrast sensitivity function (CSF) and in the magno, parvo and koniocellular visual pathways by means of a multichannel perimeter in case of an essential tremor (ET). A complete evaluation of the visual function was performed in a 69-year old patient, including the analysis of the chromatic discrimination by the Fansworth–Munsell 100 hue test, the measurement of the CSF by the CSV-1000E test, and the detection of potential alteration patterns in the magno, parvo and koniocellular visual pathways by means of a multichannel perimeter. Visual acuity and intraocular pressure (IOP) were within the ranges of normality in both eyes. No abnormalities were detected in the fundoscopic examination and in the optical coherence tomography (OCT) exam. The results of the color vision examination were also within the ranges of normality. A significant decrease in the achromatic CSFs for right eye (RE) and left eye (LE) was detected for all spatial frequencies. The statistical global values provided by the multichannel perimeter confirms that there were significant absolute sensitivity losses compared to the normal pattern in RE. In the LE, only a statistically significant decrease in sensitivity was detected for the blue-yellow (BY) channel. The pattern standard deviation (PSD) values obtained in our patient indicated that there were significant localized losses compared to the normality pattern in the achromatic channel of the RE and in the red-green (RG) channel of the LE. Some color vision alterations may be present in ET that cannot be detected with conventional color vision tests, such as the FM 100 Hue.

Tuḥfat al-ʻIrāqayn : manuscript, 1604

Title supplied by cataloger.

Thesaurus gemmarum antiquarum astriferarum : quae e compluribus dactyliothecis selectae aereis tabulis CC insculptae observationibus inlustrantur : adiectis parergis LX, Atlante Farnesiano prolegomenis, diatribis III, dissertationibus XV et indicibus /

The 200 etched plates in v. 1 are partly signed by Ioannes Franceschini (some repeated in v. 3). Etched head- and tail-pieces signed J. Verkruys, as is one of 7 folded plates in v. 3. Occasional in-text woodcuts.

Dvcvm Brabantiae chronica /

Engraved printer's device on t.p. (compasses), woodcut version on last p. Etched arms of Albrecht, Grand Duke of Austria, to whom with Isabella of Austria his consort the work is dedicated. Bound in before A1 is folded map of Brabant, dated 1599. Ill. are full-length ports. of the dukes of Brabant, with their coats of arms. Head and tail pieces, initials.

The Little Colonel's Christmas vacation /

Purchased from Gilman, Crompond, N.Y.

Poketown people, or, parables in black /

Advertisements on p. 4 at front and p. [2]-[12] at end.

Michigan Union tap room

Irving Kane and Allen B. Pond, architects. Plans for the Union were on a scale unknown at the time for "club houses" in American colleges and universities: 250 feet long and 200 feet wide. Construction began in 1916 and owing to war time difficulties was not ready to be used by students until 1919. Two new wings to the south were completed in 1936 and 1938. Another addition was begun 1954-55. Verso: 7636 MICHIGAN UNION BLDG., University of Mich., Ann Arbor Facing for stean table in tap room. Magnesium Oxycholride tiles, in buff red and blue laid in 1937. Substitute following caption for above: Michigan Union Bldg., University of Mich., Ann Arbor Facing for steam table of tap room of magnesium oxychloride in buff and brown with color inserts of red, green yelloe, blue , purple and gold. On image: 7636

Planting plan for home grounds of Mr. W. E. Haseltine. Ripon, Wisconsin.

Red, green, black ink on tracing paper; existing plantings, modified areas, parking lot outlined.Signed. 70 cm. x 45 cm. Scale: 1"=8' [from photographic copy by Lance Burgharrdt]

Planting plan for home grounds of Mr. W. E. Haseltine. Ripon, Wisconsin.

Red, green, black ink on tracing paper; existing plantings, modified areas, parking lot outlined. Signed. 70 cm. x 45 cm. Scale: 1"=8' [from photographic copy by Lance Burgharrdt]

Drain and water system plan. Grounds of Mr. L. Rueckheim.

Red, green, black ink on linen; note, "See Anderson, Lake Forest, for topo. survey"; signed; 78 x 42 cm.; Scale: 1" = 20' [from photographic copy by Lance Burgharrdt]

Die Grünen and the Israeli-Palestinian Conflict

This paper discusses the German Greens' recent policy on Israel and Palestine, from the beginning of the first red-green federal government to the present. It looks at Green Foreign Minister Joschka Fischer's diplomatic role in the Middle East, and the Greens' current very mild policy with regards to Israel, especially when compared to earlier Green attitudes to the region. This is explained with reference to both the continuing relevance of German history to German foreign policy, and the constraints that participation in the federal coalition - and supplying Germany's Foreign Minister - place on the Greens. The influence of history and power on the German Greens is further illustrated by a comparison of German Green attitudes to Israel with the US Greens' much more critical position.

Raman microscopic investigation of paint samples from the Rosalila building, Copan, Honduras

Micro-Raman spectroscopy was applied to the study of multiple layered wall paints from the Rosalila temple, Copan, Honduras, which dates to the Middle Classic period (A.D. 520 to 655). Samples of red, green and grey paint and a thick white overcoating were analysed. The paint pigments have been identified as hematite, celadonite or green earth and a combined carbon/mica mixture. By combining Raman spectroscopy with micro-ATR infrared spectroscopy and environmental scanning electron microscopy (ESEM), a detailed study has been made of the materials and processes used to make the stucco and paints. The use of green earth as a green pigment on Maya buildings has not been reported before. The combination of carbon and muscovite mica to create a reflective paint is also a novel finding.