3 research outputs found
Quark and Lepton Masses in 5D SO(10)
We construct a five dimensional supersymmetric SO(10)D grand
unified model with an orbifold as the extra
dimension. The orbifold breaks half of the supersymmetry and breaks the SO(10)
gauge symmetry down to . The Higgs mechanism is used to break the remaining gauge symmetry
the rest of the way to the Standard Model. We place matter fields variously in
the bulk and on the orbifold fixed points and the resulting massless fields are
mixtures between these brane and bulk fields. A chiral adjoint field in the
bulk gets a U(1) vacuum expectation value, resulting in an -dependent
localization of the bulk matter fields and the Standard Model Higgs field. This
Higgs field localization allows us to simultaneously explain the hierarchies
and . The model uses 11 parameters to fit the 13
independent low energy observables of the quark and charged lepton Yukawa
matrices. The model predicts the values of two quark mass combinations,
\f{m_u}{m_c} and , each of which are predicted to be
approximately above their experimental values. The remaining
observables are successfully fit at the 5% level.Comment: 52 pages, published version, includes more discussion of 6D version
of mode
Quark Mass Textures and sin 2 beta
Recent precise measurements of sin 2 beta from the B-factories (BABAR and
BELLE) and a better known strange quark mass from lattice QCD make precision
tests of predictive texture models possible. The models tested include those
hierarchical N-zero textures classified by Ramond, Roberts and Ross, as well as
any other hierarchical matrix Ansatz with non-zero 12 = 21 and vanishing 11 and
13 elements. We calculate the maximally allowed value for sin 2 beta in these
models and show that all the aforementioned models with vanishing 11 and 13
elements are ruled out at the 3 sigma level. While at present sin 2 beta and
|Vub/Vcb| are equally good for testing N-zero texture models, in the near
future the former will surpass the latter in constraining power.Comment: 1+20 pages, 2 figures, JHEP3 clas
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What can inactivity (in its various forms) reveal about affective states in non-human animals? A review
Captive/domestic animals are often described as inactive, with the implicit or explicit implication that this high level of inactivity is a welfare problem. Conversely, not being inactive enough may also indicate or cause poor welfare. In humans, too much inactivity can certainly be associated with either negative or positive affective states. In non-human animals, however, the affective states associated with elevated or suppressed levels of inactivity are still not well understood.
Part of the complexity is due to the fact that there are many different forms of inactivity, each likely associated with very different affective states. This paper has two aims. One is to identify specific forms of inactivity that can be used as indicators of specific affective states in animals. The other is to identify issues that need to be resolved before we could validly use the remaining, not yet validated forms of inactivity as indicators of affective state.
We briefly discuss how inactivity is defined and assessed in the literature, and then how inactivity in its various forms relates to affective (either negative or positive) states in animals, basing our reasoning on linguistic reports of affective states collected from humans displaying inactivity phenotypically similar to that displayed by animals in similar situations, and, when possible, on pharmacological validation. Specific forms of inactivity expressed in response to perceived threats (freezing, tonic immobility, and hiding) appear to be, to date, the best-validated indicators of specific affective states in animals. We also identify a number of specific forms of inactivity likely to reflect either negative (associated with ill-heath, boredom-like, and depression-like conditions), or positive states (e.g. ‘sun-basking’, post-consummatory inactivity), although further research is warranted before we could use those forms as indicators of the affective states. We further discuss the relationship between increased inactivity and affective states by presenting misleading situations likely to yield wrong conclusions. We conclude that more attention should be paid to inactivity in animal welfare studies: specific forms of inactivity identified in this paper are, or have the potential to be, useful indicators of affective (welfare) states in animals