White light/dark cycles

Ochromonas danica culture (code LI298) was obtained from the culture collection of the University of Texas at Austin. The cells were cultured in a modified Hoaglands medium (11) for 10 days. For both species, the culture conditions were T - 22°C pH 8.2 light intensity 100 /jEinstein/m -sec light/dark cycle of cool-white fluorescence light 16/8hr COj source bubbling with filter sterilized air. 

In each experiment, groups of 6-12 male white rats were fed diets of controlled composition for 28-30 days. All rats were individually caged in a room with controlled temperature (25 + 1°C) and a controlled light-dark cycle. 

Cultures of G. polyedra (L. polyedrum) are grown at 20 5°C in a supplemented sea water medium (Hastings and Sweeney, 1957 Hastings and Dunlap, 1986), under cool-white fluorescent lighting of a 12-hr light/12-hr dark cycle. The cultures are inoculated at densities of 100 to 500 cells/ml. After 2-4 weeks, cells are harvested by vacuum filtration on a filter paper at cell densities of 7,000-15,000 cells/ml, yielding 0.3-0.7 g wet cells per liter of culture. 

This value corresponds to semicont inuous cultures in the laboratory at high irradiance (300 W m-2, white light), under 12 h light/12 h dark cycles. 

Kinetics of Stem Elongation under 12 h White Light/12 h Dark Cycles... 

FIGURE 138.3 Wheel-running actograms of cryptochrome and rd mutants. Animals were entrained to 12 h light 12 h dark cycles, followed by constant darkness at Day 19. Numbers on the Y axis indicate days numbers on the X axis indicate time of day. White bars indicate light, black bars indicate dark (top). (From Selby, C.P., et al., Proc. NatL Acad. Sci. USA, 97, 14697, 2000. With permission.)... 

FIG. 1. Firing-rate patterns in SCN slices from wild-type mice kept in constant darkness (DD) or in 12 h light-12 h dark (LD) cycles. The running wheel activity patterns of the mice over the last 7 days prior to slice preparation is indicated above the records. (A) Circadian rhythm in multiunit activity (MUA) in the SCN of a wild-type mouse, previously kept under DD conditions and isolated at CT2 (B) Circadian rhythm in MUA activity in the SCN of a wild-type mouse, previously kept under LD conditions, and isolated at CT2. Black/ grey and black/white bars above each plot indicate the subjective night/day and night/day respectively. CT, circadian time. (Reprinted from Albus et al 2002, with permission from Elsevier Science.)... 

Fig. 9.17. Simulated structures of a ZrOz film after (a) one ALD cycle, (b) two ALD cycles, (c) three ALD cycles, and (d) four ALD cycles. Black balls are O, dark gray balls are Si, light gray balls are Zr, and white balls are H atoms.

Figure 4 Comparisons of host cage topologies, (a) The hour glass-shape of Dianin s compound 8." (b) The ellipsoidal cavity of compound 13. (c) The Chinese lantern-shaped cavity of 21. In all cases, the molecules at the front and rear of the cage, and H atoms, have been omitted for clarity. Color code C, green (opposite enantiomCTs light or dark) O, red S, yellow. The (O-H)e cycles are indicated by red and white dashes.

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