A simple model to accomodate light sterile neutrinos naturally with large mixing with the usual neutrinos has been proposed. The standard model gauge group is extended to include an SU(2)S gauge symmetry. Heavy triplet higgs scalars give small masses to the lefthanded neutrinos, while a heavy doublet higgs scalar give mixing with the sterile neutrinos of the same order of magnitude. The neutrin...

About 90% of people are right-handed and 10% are lefthanded. Handedness is associated with functional lateralization for cerebral dominance, and may also be associated with various types of psychopathology. Broadly speaking, the vast majority of humans seem to have been right-handed since the emergence of the genus Homo, some three to four million years ago. Likewise, in all societies studied, ...

It has recently been shown that by extending the minimal standard model to include a right-handed partner to ντ , it is possible to gauge the B − 3Lτ quantum number consistently. If we add two scalar triplets, one trivial (ξ1) and one nontrivial (ξ2) under B − 3Lτ , it is possible also to have desirable neutrino masses and mixing for neutrino oscillations. At the same time, a lepton asymmetry c...

Upper bounds on the CP asymmetry relevant for leptogenesis are reexamined and found weaker than in previous literature, both for hierarchical and for quasi-degenerate righthanded neutrinos. Successful leptogenesis implies the usual lower bound on right-handed neutrino masses, and an upper bound on left-handed neutrino masses (which we obtain to be 0.15 eV at 3σ) only if right-handed neutrinos a...

A minimal extension of the Standard Model is proposed, where the observed lefthanded neutrinos obtain naturally small Majorana masses from a one-loop radiative seesaw mechanism. This model has two candidates (one bosonic and one fermionic) for the dark matter of the Universe. It has a very simple structure and should be verifiable in forthcoming experiments at the Large Hadron Collider. In the ...

patients’ healthcare as medicine. Racial or ethnic discrimination is illegal in the UK under the Race Relations Act 1976. Since 2nd October 2000, religious and cultural discrimination (or lack of consideration or respect) has also become illegal under the Human Rights Act 1998, Article 9, which ensures that everyone has the right to freedom of thought, conscience and religion.1 As a result, per...

T hierarchical, multidimensional assemblies of protein–DNA structures known as the eukaryotic chromosome present both challenges and opportunities for biophysicists interested in chromatin structure (1, 2). One of the most interesting aspects of chromatin structure to come to light in recent years is the discovery that the core histone proteins alone can effectively direct the formation of mult...

Bacteria come in a variety of shapes, as most species elaborate on the ‘default’ sphere to resemble ovoids, rods, bend rods, spirals, branched filaments or other more complicated forms. How cells that are under considerable turgor pressure maintain a nonspherical shape is unclear, though it is known to depend on structural elements on either side of the cytoplasmic membrane: the murein (peptido...

This thesis is concerned with the reflection and transmission properties of layered lefthanded materials (LHM). In particular, the reflection properties of (LHM) slabs are studied for the Goos-Hiinchen (GH) lateral shift phenomenon. We demonstrate a unique GH lateral shift phenomenon, which shows that both positive and negative shifts can be achieved using the same LHM slab configuration. This ...

In the light of the recent muon (gμ − 2) result by the E821 experiment at the Brookhaven National Laboratory, we study the event rates of the charged leptonflavour-violating (LFV) processes in the supersymmetric standard model (SUSY SM) with the heavy right-handed neutrinos (SUSY see-saw model). Since the left-handed sleptons get the LFV masses via the neutrino Yukawa interaction in this model,...