Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Coherent Control of Optogenetic Switching by Stimulated Depletion
  Quenching   Optogenetics is a revolutionary new field of biotechnology, achieving optical
control over biological functions in living cells by genetically inserting
light sensitive proteins into cellular signaling pathways. Applications of
optogenetic switches are expanding rapidly, but the technique is hampered by
spectral cross-talk: the broad absorption spectra of compatible biochemical
chromophores limits the number of switches that can be independently controlled
and restricts the dynamic range of each switch. In the present work we develop
and implement a non-linear optical photoswitching capability, Stimulated
Depletion Quenching (SDQ), is used to overcome spectral cross-talk by
exploiting the molecules' unique dynamic response to ultrashort laser pulses.
SDQ is employed to enhance the control of Cph8, a photo-reversible phytochrome
based optogenetic switch designed to control gene expression in E. Coli
bacteria. The Cph8 switch can not be fully converted to it's biologically
inactive state ($P_{FR}$) by linear photos-witching, as spectral cross-talk
causes a reverse photoswitching reaction to revert to it back to the active
state ($P_{R}$). SDQ selectively halts this reverse reaction while allowing the
forward reaction to proceed. The results of this proof of concept experiment
lay the foundation for future experiments that will use optimal pulse shaping
to further enhance control of Cph8 and enable simultaneous, multiplexed control
of multiple optogenetic switches.

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The categories of this paper are: nlin
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The categories of this paper are: hep-lat
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The categories of this paper are: cmp-lg
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The categories of this paper are: math
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The categories of this paper are: gr-qc
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The categories of this paper are: physics
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The categories of this paper are: chao-dyn
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The categories of this paper are: econ
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The categories of this paper are: adap-org
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The categories of this paper are: q-fin
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The categories of this paper are: ao-sci
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The categories of this paper are: chem-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: supr-con
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The categories of this paper are: dg-ga
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The categories of this paper are: solv-int