21,029 research outputs found
Hierarchic trees with branching number close to one: noiseless KPZ equation with additional linear term for imitation of 2-d and 3-d phase transitions.
An imitation of 2d field theory is formulated by means of a model on the
hierarhic tree (with branching number close to one) with the same potential and
the free correlators identical to 2d correlators ones.
Such a model carries on some features of the original model for certain scale
invariant theories. For the case of 2d conformal models it is possible to
derive exact results. The renormalization group equation for the free energy is
noiseless KPZ equation with additional linear term.Comment: latex, 5 page
The needs of people with dementia living at home from user, caregiver and professional perspectives: a cross-sectional survey
Few reports have been published about differences in perspectives on perceived needs among community-residing people with dementia, their family caregivers, and professionals. The aim of this study was to compare these perspectives
Pathogenicity of the root-knot nematode Meloidogyne javanica on potato
Host–parasite relationships and pathogenicity of
Meloidogyne javanica
on potatoes (newly recorded from Malta) were
studied under glasshouse and natural conditions. Potato cvs Cara and Spunta showed a typical susceptible reaction to
M. javanica
under natural and artificial infections, respectively. In potato tubers,
M. javanica
induced feeding sites that
consisted of three to four hypertrophied giant cells per adult female. Infection of feeder roots by the nematode resulted
in mature large galls which usually contained at least one mature female and egg mass. In both tubers and roots, feeding
sites were characterized by giant cells containing granular cytoplasm and many hypertrophied nuclei. Cytoplasm in giant
cells was aggregated alongside the thickened cell walls. Stelar tissues within galls appeared disorganized. The relationship
between initial nematode population density (
P
) [0–64 eggs + second-stage juveniles (J2s) per cm
3
soil] and growth of
cv. Spunta potato seedlings was tested under glasshouse conditions. A Seinhorst model [
y = m
+ (1
−
m
)
z
(
P
−
T
)
] was fitted
to fresh shoot weight and shoot height data of nematode-inoculated and control plants. Tolerance limits (
T
) for fresh
shoot weight and shoot height of cv. Spunta plants infected with
M. javanica
were 0·50 and 0·64 eggs + J2s per cm
3
soil,
respectively. The
m
parameter in that model (i.e. the minimum possible
y
-values) for fresh shoot weight and shoot height
were 0·60 and 0·20, respectively, at
P
= 64 eggs + J2s per cm
3
soil. Root galling was proportional to the initial nematode
population density. Maximum nematode reproduction rate was 51·2 at a moderate initial population density (
P
= 4
eggs + J2s per cm
3
soil).peer-reviewe
Charged particle dynamics in the presence of non-Gaussian L\'evy electrostatic fluctuations
Full orbit dynamics of charged particles in a -dimensional helical
magnetic field in the presence of -stable L\'evy electrostatic
fluctuations and linear friction modeling collisional Coulomb drag is studied
via Monte Carlo numerical simulations. The L\'evy fluctuations are introduced
to model the effect of non-local transport due to fractional diffusion in
velocity space resulting from intermittent electrostatic turbulence. The
probability distribution functions of energy, particle displacements, and
Larmor radii are computed and showed to exhibit a transition from exponential
decay, in the case of Gaussian fluctuations, to power law decay in the case of
L\'evy fluctuations. The absolute value of the power law decay exponents are
linearly proportional to the L\'evy index . The observed anomalous
non-Gaussian statistics of the particles' Larmor radii (resulting from outlier
transport events) indicate that, when electrostatic turbulent fluctuations
exhibit non-Gaussian L\'evy statistics, gyro-averaging and guiding centre
approximations might face limitations and full particle orbit effects should be
taken into account.Comment: 5 pages, 5 figures. Accepted as a letter in Physics of Plasma
Characterization and analysis of azimuthally sensitive correlations
A unified framework for describing the azimuthal dependence of two-particle
correlations in heavy-ion collisions is introduced, together with the methods
for measuring the corresponding observables. The generalization to azimuthal
correlations between more than two particles is presented.Comment: 7 pages; talk given at Hot Quarks 2004, Taos (NM), July 18-24,200
El proceso de revisión del Concordato de 1953.
Material incluido en el volumen especial de la revista del Instituto MartÃn de Azpilcueta, Universidad de Navarra : Ius Canonicum (1999), en honor de Javier Hervada
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