41 research outputs found
Unifying darko-lepto-genesis with scalar triplet inflation
We present a scalar triplet extension of the standard model to unify the
origin of inflation with neutrino mass, asymmetric dark matter and
leptogenesis. In presence of non-minimal couplings to gravity the scalar
triplet, mixed with the standard model Higgs, plays the role of inflaton in the
early Universe, while its decay to SM Higgs, lepton and dark matter
simultaneously generate an asymmetry in the visible and dark matter sectors. On
the other hand, in the low energy effective theory the induced vacuum
expectation value of the triplet gives sub-eV Majorana masses to active
neutrinos. We investigate the model parameter space leading to successful
inflation as well as the observed dark matter to baryon abundance. Assuming the
standard model like Higgs mass to be at 125-126 GeV, we found that the mass
scale of the scalar triplet to be ~ O(10^9) GeV and its trilinear coupling to
doublet Higgs is ~ 0.09 so that it not only evades the possibility of having a
metastable vacuum in the standard model, but also lead to a rich
phenomenological consequences as stated above. Moreover, we found that the
scalar triplet inflation strongly constrains the quartic couplings, while
allowing for a wide range of Yukawa couplings which generate the CP asymmetries
in the visible and dark matter sectors.Comment: (v1) 29 pages, 11 figures; (v2) 30 pages, 1 figure added and
discussions expanded, to appear in Nuclear Physics
Enhancing the recovery of oilseed rape seed oil bodies (oleosomes) using bicarbonate-based soaking and grinding media
An aqueous process for the recovery of oil bodies from rapeseed using sodium bicarbonate-based soaking and grinding media (pH 9.5) was investigated. The effect of the ratio between seed and mass of media during grinding and molarity of the medium used on oil body integrity, purity and storage stability have been studied. The grinding of seeds in solution at a ratio of 1:7 (w/w) significantly improved the quality of oil body suspension to a size more in-line with that seen in vivo (average D4,3 of 1.19 μm). The purity and the composition of the recovered oil bodies depends on the molarity of medium used; the use of a sodium bicarbonate solution (pH 9.5, 0.1 M) in the grinding and washing steps produced oil body preparations with the same purity as that resulting from washing a crude preparation with 9 M urea. The resultant emulsion had improved physical stability over a storage period of one month
Resolution of dark matter problem in f(T) gravity
In this paper, we attempt to resolve the dark matter problem in f(T) gravity.
Specifically, from our model we successfully obtain the flat rotation curves of
galaxies containing dark matter. Further, we obtain the density profile of dark
matter in galaxies. Comparison of our analytical results shows that our
torsion-based toy model for dark matter is in good agreement with empirical
data-based models. It shows that we can address the dark matter as an effect of
torsion of the space.Comment: 14 pages, 3 figure
Electroweak Baryogenesis and Dark Matter with an approximate R-symmetry
It is well known that R-symmetric models dramatically alleviate the SUSY
flavor and CP problems. We study particular modifications of existing
R-symmetric models which share the solution to the above problems, and have
interesting consequences for electroweak baryogenesis and the Dark Matter (DM)
content of the universe. In particular, we find that it is naturally possible
to have a strongly first-order electroweak phase transition while
simultaneously relaxing the tension with EDM experiments. The R-symmetry (and
its small breaking) implies that the gauginos (and the neutralino LSP) are
pseudo-Dirac fermions, which is relevant for both baryogenesis and DM. The
singlet superpartner of the U(1)_Y pseudo-Dirac gaugino plays a prominent role
in making the electroweak phase transition strongly first-order. The
pseudo-Dirac nature of the LSP allows it to behave similarly to a Dirac
particle during freeze-out, but like a Majorana particle for annihilation today
and in scattering against nuclei, thus being consistent with current
constraints. Assuming a standard cosmology, it is possible to simultaneously
have a strongly first-order phase transition conducive to baryogenesis and have
the LSP provide the full DM relic abundance, in part of the allowed parameter
space. However, other possibilities for DM also exist, which are discussed. It
is expected that upcoming direct DM searches as well as neutrino signals from
DM annihilation in the Sun will be sensitive to this class of models.
Interesting collider and Gravity-wave signals are also briefly discussed.Comment: 50 pages, 10 figure
Respiratory disease and the role of oral bacteria
The relationship between oral health and systemic conditions, including the association between poor oral hygiene, periodontal disease, and respiratory disease, has been increasingly debated over recent decades. A considerable number of hypotheses have sought to explain the possible role of oral bacteria in the pathogenesis of respiratory diseases, and some clinical and epidemiological studies have found results favoring such an association. This review discusses the effect of oral bacteria on respiratory disease, briefly introduces the putative biological mechanisms involved, and the main factors that could contribute to this relationship. It also describes the role of oral care for individuals who are vulnerable to respiratory infections