10 research outputs found
Dark Matter Candidates: A Ten-Point Test
An extraordinarily rich zoo of non-baryonic Dark Matter candidates has been
proposed over the last three decades. Here we present a 10-point test that a
new particle has to pass, in order to be considered a viable DM candidate: I.)
Does it match the appropriate relic density? II.) Is it {\it cold}? III.) Is it
neutral? IV.) Is it consistent with BBN? V.) Does it leave stellar evolution
unchanged? VI.) Is it compatible with constraints on self-interactions? VII.)
Is it consistent with {\it direct} DM searches? VIII.) Is it compatible with
gamma-ray constraints? IX.) Is it compatible with other astrophysical bounds?
X.) Can it be probed experimentally?Comment: 29 pages, 12 figure
Dark matter with invisible light from heavy double charged leptons of almost-commutative geometry?
A new candidate of cold dark matter arises by a novel elementary particle
model: the almostcommutative AC-geometrical framework. Two heavy leptons are
added to the Standard Model, each one sharing a double opposite electric charge
and an own lepton flavor number The novel mathematical theory of
almost-commutative geometry [1] wishes to unify gauge models with gravity. In
this scenario two new heavy (m_L>100GeV), oppositely double charged leptons
(A,C),(A with charge -2 and C with charge +2), are born with no twin quark
companions. The model naturally involves a new U(1) gauge interaction,
possessed only by the AC-leptons and providing a Coulomblike attraction between
them. AC-leptons posses electro-magnetic as well as Z-boson interaction and,
according to the charge chosen for the new U(1) gauge interaction, a new
"invisible light" interaction. Their final cosmic relics are bounded into
"neutral" stable atoms (AC) forming the mysterious cold dark matter, in the
spirit of the Glashow's Sinister model. An (AC) state is reached in the early
Universe along a tail of a few secondary frozen exotic components. They should
be now here somehow hidden in the surrounding matter. The two main secondary
manifest relics are C (mostly hidden in a neutral (Cee) "anomalous helium"
atom, at a 10-8 ratio) and a corresponding "ion" A bounded with an ordinary
helium ion (4He); indeed the positive helium ions are able to attract and
capture the free A fixing them into a neutral relic cage that has nuclear
interaction (4HeA).Comment: This paper has been merged with [astro-ph/0603187] for publication in
Classical and Quantum Gravit
The neurogenic bladder: medical treatment
Neurogenic bladder sphincter dysfunction (NBSD) can cause severe and irreversible renal damage and bladder-wall destruction years before incontinence becomes an issue. Therefore, the first step in adequate management is to recognize early the bladder at risk for upper- and lower-tract deterioration and to start adequate medical treatment proactively. Clean intermittent catheterization combined with anticholinergics (oral or intravesical) is the standard therapy for NBSD. Early institution of such treatment can prevent both renal damage and secondary bladder-wall changes, thereby potentially improving long-term outcomes. In children with severe side effects or with insufficient suppression of detrusor overactivity despite maximal dosage of oral oxybutynin, intravesical instillation is an effective alternative. Intravesical instillation eliminates systemic side effects by reducing the first-pass metabolism and, compared with oral oxybutynin, intravesical oxybutynin is a more potent and long-acting detrusor suppressor. There is growing evidence that with early adequate treatment, kidneys are saved and normal bladder growth can be achieved in children so they will no longer need surgical bladder augmentation to achieve safe urinary continence in adolescence and adulthood
Protein/Emulsifier Interactions
An important consequence of protein-lipid interaction is the effect on stability of the protein in solution as well as on its behavior at interfaces. Here we will discuss key aspects of protein aggregation and unfolding as well as the effects of protein structure (random coil proteins versus globular) that are relevant for our understanding protein-lipid interaction. The main types of emulsifiers are the (1) aqueous soluble, surfactant type and (2) lipids with low aqueous solubility. The monomer concentration as defined by cmc is an important parameter for the soluble lipids. For emulsifiers with low aqueous solubility the emulsifier self-assembly structure and its properties control the interaction with proteins. We will therefore summarize the main features of lipid self-assembly. It also allows us to define different plausible scenarios and principles and models for factors that control the interactions in real food (and Pharmaceutical) systems. For the food applications the fate of the lipid during digestion is important and therefore we will discuss some aspects of enzyme-catalyzed lipolysis in terms of the structural evolution. New products and concepts of using protein/emulsifier interactions will be exemplified by illustrating how food nanotechnology possibly can be used for the delivery of functionality