The Amber Project: A Survey of Methods and Inks for the Reproduction of the Color of Translucent Objects

Unlike regular pigments based on selective light absorption, the so-called “effect pigments″ are based on the phenomena of structural color, or selective reflectance. Structural color has appealing aesthetic qualities, such as angle-dependent hue, and is able to produce lightfast colors. When used as a pigment, however, the gamut of the print is more limited, the color is difficult to measure, and therefore color management and preprint process become challenging. The aim of this paper is to compare the behavior of effect pigments in the processes of lithographic and screen printing with standard pigments used in so-called process inks, and to analyze their optical properties when used on their own or in combination with absorption pigments. An image of amber beads was printed as screen prints and lithographs. Three sets of inks were used: Set one: Standard process inks in the colors cyan, magenta, yellow and black (CMYK); set two: RGB inks formulated with Merck Spectraval™ pearlescent pigments which allow additive red, green, blue printing on a black substrate; and set three: golden inks formulated with pigments from the Merck Iriodin™ and Pyrisma™ effect pigment range. The image was printed on white and black paper. The optical appearance was assessed visually, and spectra and color coordinates were measured.

A high-performance visible laser rewritable black paper

An automatically printable, classic, and frequently usable high-performance black visible-light-responsive paper has been fabricated.

The Pioneer Mixed a “Batch of ‘Congrats’”

In 1949, after WJMR fired Vernon Winslow, the black paper the Louisiana Weekly hired him as an advertising agent. He also wrote a nightlife gossip column called “Boogie-beat Jive.” In 1950 WMRY was the first local radio station to revamp its programming from white-oriented to exclusively black content. In his column, Winslow critiqued the on-air presentations of the new black DJs whom WMRY hired. He chimed about the good and the bad. George "Tex" Stephens was one of them whom he criticized and later praised. In 1957 WMRY phased out and morphed into WYLD. A year later, WBOK emerged as the city's first racially mixed station playing hillbilly music along with popular black music.

A role for GLABRA1 in dark-induced senescence

The GLABRA (GL1) gene, belonging to the transcription factor-encoding myb gene family, is responsible for trichome formation in Arabidopsis thaliana (L.) Heynh. The leaves and stems of glabra1 mutant plants are devoid of trichomes. Having an easily observable phenotype, the gl1 mutation was one of the first markers established for genetic mapping of Arabidopsis thaliana. Since then, the GL1 gene has been assigned roles in other processes, also related to leaf structure. In this study we present some previously undescribed effects of the gl1 mutation on dark-induced senescence. This process was induced by covering selected mature leaves of Columbia wild-type and gl1 Arabidopsis with black paper for 4 days, while the plants remained growing in a normal photoperiod. While no visible differences in the external symptoms of senescence could be observed in the darkened leaves, the expression of senescence-associated genes was significantly lower in gl1 plants as compared to the wild type. The darkening of leaves led to a decrease in photosynthetic activity and the expression of photosynthesis-associated genes, in comparison to the control leaves. This effect was much less pronounced in gl1 than in the wild type plants. Therefore, gl1 plants seem to be less susceptible to dark-induced aging, suggesting a possible role for the GL1 gene in controlling the onset and progress of senescence. This result is also of practical importance, since gl1 is the genetic background of many other mutants. It may therefore be advisable to revise some of the results obtained with such mutants in light of findings presented here.

The Perspectives of Teachers and Paraeducators on the Relationship between Classroom Clutter and Learning Experiences for Students with Cerebral Visual Impairment

Introduction Cerebral visual impairment (CVI) typically affects children's overall functioning in visually cluttered environments. This study aims to consider whether the removal of classroom clutter ameliorates visual problems and the associated behavioral difficulties for these children. Methods Two classrooms at a special school were de-cluttered. Changes included: covering glass panels with thick black paper; hanging sheets over open shelving; creating areas of blank wall in front of the student to focus attention on work; removing unnecessary equipment and furniture; and taking down information on windows and walls, and that hanging from ceilings. Teachers, paraeducators, and students worked in these classrooms for two weeks, following typical daily routines. Observations by teachers and paraeducators of students’ behavior and learning experiences before and after de-cluttering were sought through interviews. Findings The perspectives of the teachers and paraeducators were that de-cluttering had a positive effect on the students’ learning experiences and behavior and also on their own functioning. They also considered the fact that creation of learning spaces lined with black paper resulted in greater attention and focus, but that students continued to be distracted by the noise and movement of others. Discussion The potential link between cluttered classrooms and students’ functioning and behavior indicates that visual clutter may amplify the visual difficulties associated with CVI and distract the students from learning activities, and is in line with current literature. Changes to classroom layouts that include specific areas for different learning activities, including “black hubs,” may therefore benefit students with CVI. Implications for practitioners This pilot study suggests that the elimination of classroom clutter and the creation of black hub learning spaces enhances functioning and merits further investigation. A study that compares specific behaviors and performances, before and after implementation of de-cluttering strategies, might also determine whether the positive effects described by the teachers can be further corroborated.

The Effect of Different Bags on Chlorophyll and Carotenoids in the Peel of Chinhuang Mango

The effect of different fruit bags on the content of chlorophyll and carotenoids in the fruit peel of Chinhuang mango during normal storage and after-ripening process was studied. The results showed that the content of chlorophyll and carotenoid in the bag was significantly lower than that of the control fruit. The skin color of the white paper bag fruit and the no bagged bag fruit was green during the green ripening process, while the outer yellow inner black paper bag fruit showed a yellow green halo. When ripe, the control fruit is yellowish green and orange red. The white paper bag fruit is greenish orange yellow, and the outside yellow inside black composite paper bag fruit is golden yellow.

The Staircase Gelb Illusion

Adhemar Gelb showed that if a piece of black paper is suspended in midair and illuminated by a projector, it appears white. However, when a white paper is brought into the projector beam and placed next to or surrounding the black paper, the black paper once again appears black. In the staircase Gelb illusion, a succession of increasingly lighter papers, dark gray, middle gray, light gray, and finally white, is brought into the projector beam. Each time a lighter paper is added it appears white, and this causes the prior paper to darken, due to the highest luminance rule of anchoring. When all five shades are present within the beam, the gamut of perceived values is compressed relative to the actual values. The compression requires the simultaneous juxtaposition of different illumination levels and illustrates the codetermination principle of Kardos.