3,386 research outputs found
Fundamental Principles in Bacterial Physiology - History, Recent progress, and the Future with Focus on Cell Size Control: A Review
Bacterial physiology is a branch of biology that aims to understand
overarching principles of cellular reproduction. Many important issues in
bacterial physiology are inherently quantitative, and major contributors to the
field have often brought together tools and ways of thinking from multiple
disciplines. This article presents a comprehensive overview of major ideas and
approaches developed since the early 20th century for anyone who is interested
in the fundamental problems in bacterial physiology. This article is divided
into two parts. In the first part (Sections 1 to 3), we review the first
`golden era' of bacterial physiology from the 1940s to early 1970s and provide
a complete list of major references from that period. In the second part
(Sections 4 to 7), we explain how the pioneering work from the first golden era
has influenced various rediscoveries of general quantitative principles and
significant further development in modern bacterial physiology. Specifically,
Section 4 presents the history and current progress of the `adder' principle of
cell size homeostasis. Section 5 discusses the implications of coarse-graining
the cellular protein composition, and how the coarse-grained proteome `sectors'
re-balance under different growth conditions. Section 6 focuses on
physiological invariants, and explains how they are the key to understanding
the coordination between growth and the cell cycle underlying cell size control
in steady-state growth. Section 7 overviews how the temporal organization of
all the internal processes enables balanced growth. In the final Section 8, we
conclude by discussing the remaining challenges for the future in the field.Comment: Published in Reports on Progress in Physics.
(https://doi.org/10.1088/1361-6633/aaa628) 96 pages, 48 figures, 7 boxes, 715
reference
Storing images in warm atomic vapor
Reversible and coherent storage of light in atomic medium is a key-stone of
future quantum information applications. In this work, arbitrary
two-dimensional images are slowed and stored in warm atomic vapor for up to 30
s, utilizing electromagnetically induced transparency. Both the intensity
and the phase patterns of the optical field are maintained. The main limitation
on the storage resolution and duration is found to be the diffusion of atoms. A
techniqueanalogous to phase-shift lithography is employed to diminish the
effect of diffusion on the visibility of the reconstructed image
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