1,503 research outputs found
Niemann-Pick type C disease - the tip of the iceberg? A review of neuropsychiatric presentation, diagnosis and treatment
Niemann-Pick type C (NP-C) disease is a rare neurodegenerative
lysosomal storage disorder. It is highly heterogeneous, and there is limited awareness
of a substantial subgroup that has an attenuated adolescent/adult-onset disease.
In these patients psychiatric features, often a psychosis, may dominate the initial
impression, although often there is an associated ataxia and cognitive impairment.
Typically, patients experience a substantial diagnostic delay. In this review we
highlight the importance of early recognition and discuss the pathophysiology,
neuropsychiatric presentation and recent changes in the investigation and work-up of
these patients, and treatment options.http://www.apa.org/pubs/journals/bulam2018Paediatrics and Child Healt
DNA electrophoresis studied with the cage model
The cage model for polymer reptation, proposed by Evans and Edwards, and its
recent extension to model DNA electrophoresis, are studied by numerically exact
computation of the drift velocities for polymers with a length L of up to 15
monomers. The computations show the Nernst-Einstein regime (v ~ E) followed by
a regime where the velocity decreases exponentially with the applied electric
field strength. In agreement with de Gennes' reptation arguments, we find that
asymptotically for large polymers the diffusion coefficient D decreases
quadratically with polymer length; for the cage model, the proportionality
coefficient is DL^2=0.175(2). Additionally we find that the leading correction
term for finite polymer lengths scales as N^{-1/2}, where N=L-1 is the number
of bonds.Comment: LaTeX (cjour.cls), 15 pages, 6 figures, added correctness proof of
kink representation approac
Levi-Civita Effect in the polarizable vacuum (PV) representation of general relativity
The polarizable vacuum (PV) representation of general relativity (GR),
derived from a model by Dicke and related to the "TH-epsilon-mu" formalism used
in comparative studies of gravitational theories, provides for a compact
derivation of the Levi-Civita Effect (both magnetic and electric), herein
demonstrated.Comment: 8 page
Tunneling and Metastability of continuous time Markov chains
We propose a new definition of metastability of Markov processes on countable
state spaces. We obtain sufficient conditions for a sequence of processes to be
metastable. In the reversible case these conditions are expressed in terms of
the capacity and of the stationary measure of the metastable states
Gulf Stream remote forcing of shelfbreak currents in the Mid‐Atlantic Bight
The “Slope Sea” is a narrow band of ocean that lies between the Gulf Stream and the continental shelf edge in the Mid‐Atlantic Bight. It is composed primarily of slopewater, and a closed cyclonic gyre circulates within the upper few hundred meters of its western end. A two‐year time series of current measurements in this region has shown that the southwestward flowing shelfbreak currents along the shoreward flank of the gyre are directly related to the position of the Gulf Stream, which is typically some 150 to 300 km seaward of the shelfbreak. The mean monthly shelfbreak currents are strongest, towards the southwest at about 30–40 cm s−1, when the Stream is within 150 km of the shelf edge, whereas those currents are close to zero when the Stream is about 300 km away
Extraction of the coupling constant from NN scattering data
We reexamine Chew's method for extracting the coupling constant from
np differential cross section measurements. Values for this coupling are
extracted below 350 MeV, in the potential model region, and up to 1 GeV. The
analyses to 1~GeV have utilized 55 data sets. We compare these results to those
obtained via mapping techniques. We find that these two methods give
consistent results which are in agreement with previous Nijmegen
determinations.Comment: 12 pages of text plus 2 figures. Revtex file and postscript figures
available via anonymous FTP at ftp://clsaid.phys.vt.edu/pub/n
Identity of the imaginary-time and real-time thermal propagators for scalar bound states in a one-generation Nambu-Jona-Lasinio model
By rigorous reanalysis of the results, we have proven that the propagators at
finite temperature for scalar bound states in one-generation fermion condensate
scheme of electroweak symmetry breaking are in fact identical in the
imaginary-time and the real-time formalism. This dismisses the doubt about
possible discrepancy between the two formalisms in this problem. Identity of
the derived thermal transformation matrices of the real-time matrix propagators
for scalar bound states without and with chemical potential and the ones for
corresponding elementary scalar particles shows similarity of thermodynamic
property between the two types of particles. Only one former inference is
modified, i.e. when the two flavors of fermions have unequal nonzero masses,
the amplitude of the composite Higgs particle will decay instead grow in time.Comment: 5 pages, revtex4, no figure
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