296 research outputs found
Inert scalars and vacuum metastability around the electroweak scale
We analyse effective potential around the electroweak (EW) scale in the
Standard Model extended with a heavy scalar doublet. We show that the
additional scalars can have a strong impact on vacuum stability. Although the
additional heavy scalars may improve the behaviour of running Higgs
self-coupling at large field values, we prove that they can destabilise the
vacuum due to EW-scale effects. A new EW symmetry conserving minimum of the
effective potential can appear rendering the electroweak symmetry breaking
minimum meta- or unstable. However, for the case of the inert doublet model
(IDM) with a 125 GeV Higgs boson we demonstrate that the parameter space region
where the vacuum is meta- or unstable cannot be reconciled with the constraints
from perturbative unitarity, electroweak precision tests and dark matter relic
abundance measurements.Comment: 15 pages, 4 figures, v2: references added, discussion extended (one
figure added), results unchanged, matches published versio
The history and recent advances in research of polyprenol and its derivatives
The reduction pathway leading to the formation of dolichol was clarified in 2010 with the identification of SRD5A3, which is the polyprenol reductase. The finding inspired us to reanalyze the length of the major chain of polyprenol and dolichol from several plant leaves, including mangrove plants, as well as from animal and fish livers by 2D-TLC. Polyprenol- and dolichol derived metabolites such as polyprenylacetone and epoxydolichol were found together with
rubber-like prenol. This review focuses on analyses of polyprenol and its derivatives, including recently found epoxypolyprenol and polyprenylacetone. Attention has also been paid to the chromatographic behavior of rubber-like prenol on TLC
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