Proliferations of portable devices and increasing design complexity have made low power consumption one of the major factors guiding digital design. The clock distribution and generation circuitry forms a critical component of current synchronous digital system and is known to consume large amount the power budget of the current processor. This paper describes the importance of the sinusoidal c...

and the resulting dimer can bind to E box elements and activate transcription (references in Bunger et al., 2000; Maemura et al., 2000). Moreover, Bmal2 is expressed The molecular dissection of the mammalian circadian in the SCN. The discovery of Bmal2 raised questions clock continues to yield exciting and important discover-concerning the importance of Bmal1 in the SCN clock-ies. Here we revie...

This paper describes an automated layout design technique for the gated-clock design. Two issues must be considered for gated-clock circuits to work correctly. One is to minimize the skew for gated-clock nets. The other is to keep timing constraints for enable-logic parts. We propose the layout design technique to taking these things into consideration. We developed GatedClock Tree Synthesizer ...

Several varieties of clock drivers with 1ns or less skew from output-to-output are available from Motorola. Microprocessor-based systems are now running at 33MHz and beyond, and system clock distribution at these frequencies mandate the use of low skew clock drivers. Unfortunately, just plugging a high performance clock driver into a system does not guarantee trouble free operation. Only carefu...

Cryptochrome (CRY), a photoreceptor for the circadian clock in Drosophila, binds to the clock component TIM in a light-dependent fashion and blocks its function. In mammals, genetic evidence suggests a role for CRYs within the clock, distinct from hypothetical photoreceptor functions. Mammalian CRY1 and CRY2 are here shown to act as light-independent inhibitors of CLOCK-BMAL1, the activator dri...

In this paper, a new robust non-overlapping twophase clock generator with adjustable duty cycle is proposed. The generator is based on a differential negative edge trigged D flip-flop and has small area and power consumption. The maximal clock rate and delay are also improved reaching a clock frequency of 1.0 GHz in a standard 0.35 μm CMOS process. The new clock generator is inherently glitch a...

Circadian clock oscillation emerges in mouse embryo in the later developmental stages. Although circadian clock development is closely correlated with cellular differentiation, the mechanisms of its emergence during mammalian development are not well understood. Here, we demonstrate an essential role of the posttranscriptional regulation of Clock subsequent to the cellular differentiation for t...

The role of peripheral vs. central circadian rhythms and Clock in the maintenance of metabolic homeostasis and with aging was examined by using Clock(Delta19)+MEL mice. These have preserved suprachiasmatic nucleus and pineal gland rhythmicity but arrhythmic Clock gene expression in the liver and skeletal muscle. Clock(Delta19)+MEL mice showed fasting hypoglycemia in young-adult males, fasting h...

Colonic morphology and function change significantly during ontogenesis. In mammals, many colonic physiological functions are temporally controlled by the circadian clock in the colon, which is entrained by the central circadian clock in the suprachiasmatic nuclei (SCN). The aim of this present study was to ascertain when and how the circadian clock in the colon develops during the perinatal pe...

The sensitive to freezing6 (sfr6) mutant of Arabidopsis (Arabidopsis thaliana) is late flowering in long days due to reduced expression of components in the photoperiodic flowering pathway in long-day photoperiods. Microarray analysis of gene expression showed that a circadian clock-associated motif, the evening element, was overrepresented in promoters of genes down-regulated in sfr6 plants. A...