Reset the clock

This is exploited in the technique of uranium-thorium dating, which involves measuring the amount of thorium-230 that has accumulated in a substance by decay of uranium. If the object contained no thorium at all when it was formed, the ratio of remaining U to accumulated °Th is a measure of the age. The object being dated must not have had access to sources of fresh uranium that could reset the clock. This is true, for example, of coral left stranded on fossil beaches when sea levels recede, or of... 

In order to affect the system-bath coupling and control, or modulate, the decoherence due to this coupling, one must dynamically modulate the system faster than the correlation time. Slower modulation will have no effect on the loss of coherence and will thus not be able to control it. Modulating the system faster than the correlation time can effectively reset the clock. Applying a modulation sequence repeatedly can thus drastically change the decoherence and impose a continued coherent evolution of the system-bath coupling [46, 94]. 

Figure 6. Spin frame representation of a spin-vector by flagpole normalized pair representation a,b over the Poincare sphere in Minkowski tetrad (l,x,y,z) form (n representation) and for three timeframes or sampling intervals providing overall (t]. r ) a Cartan-Weyl form representation. The sampling intervals reset the clock after every sampling of instantaneous polarization. Thus polarization modulation is represented by the collection of samplings over time. Minkowski form after Penrose and Rindler [28]. This is an SU(2) Gd hx) m C over it representation, not an SO(3) Q(to, 8) in C representation over 2it. This can be seen by noting that an b or bt-z a over it, not 2n, while the polarization modulation in SO(3) repeats at a period of 2it.

Noguchi, T. and Watanabe, K. 2005. Tetrodotoxin resets the clock. Eur. J. Neurosci. 21, 3361-3367. Noguchi, T., Konosu, S., and Hashimoto, Y. 1969. Identity of the crab toxin with saxitoxin. Toxicon 7, 325-326. 

Manual proof testing reduces the probability of failure on demand because it effectively resets the clock on the cumulative probability of a failure. After a proof test has been successfully carried out the cumulative probability figure is very low and begins to rise with time. Hence the average probability between proof tests is lower than the untested and cumulative probability of failure (which would eventually approach 100%). 

If, at time, tg, the creep experiment has reached a steady-state (constant shear rate) then the recovered strain no longer depends on tg, and it is convenient to set tg equal to zero, thus resetting the clock . This leads to ... 

FIGURE 138.4 Molecular mechanism of circadian rhythm. Circadian rhythm is established by a negative feedback loop. This simplified model shows transcriptional activation by the Bmal-Clock heterodimer to drive transcription from E-box containing genes such as Per and Cry. Per and Cry then feed back to inhibit their own transcription. Light input resets the clock by rapid induction of the per transcript through the CRE element. 

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