554 research outputs found
Analysis of free proteinogenic intracellular amino acids of Neurospora by ion exchange chromatography
Analysis of free proteinogenic intracellular amino acids of Neurospora by ion exchange chromatograph
Cyanocobalamin in mycelium of Neurospora sitophila
Cyonocobolamine in N. sitophil
An improved cosmic crystallography method to detect holonomies in flat spaces
A new, improved version of a cosmic crystallography method for constraining
cosmic topology is introduced. Like the circles-in-the-sky method using CMB
data, we work in a thin, shell-like region containing plenty of objects. Two
pairs of objects (quadruplet) linked by a holonomy show a specific distribution
pattern, and three filters of \emph{separation, vectorial condition}, and
\emph{lifetime of objects} extract these quadruplets. Each object is
assigned an integer , which is the number of candidate quadruplets
including as their members. Then an additional device of -histogram
is used to extract topological ghosts, which tend to have high values of .
In this paper we consider flat spaces with Euclidean geometry, and the filters
are designed to constrain their holonomies. As the second filter, we prepared
five types that are specialized for constraining specific holonomies: one for
translation, one for half-turn corkscrew motion and glide reflection, and three
for -th turn corkscrew motion for and 6. {Every multiconnected
space has holonomies that are detected by at least one of these five filters.}
Our method is applied to the catalogs of toy quasars in flat -CDM
universes whose typical sizes correspond to . With these simulations
our method is found to work quite well. {These are the situations in which
type-II pair crystallography methods are insensitive because of the tiny number
of ghosts. Moreover, in the flat cases, our method should be more sensitive
than the type-I pair (or, in general, -tuplet) methods because of its
multifilter construction and its independence from .}Comment: 12 pages, 8 figures, accepted for publication in A&A (2011
Cosmic microwave anisotropies in an inhomogeneous compact flat universe
The anisotropies of the cosmic microwave background (CMB) are computed for
the half-turn space E_2 which represents a compact flat model of the Universe,
i.e. one with finite volume. This model is inhomogeneous in the sense that the
statistical properties of the CMB depend on the position of the observer within
the fundamental cell. It is shown that the half-turn space describes the
observed CMB anisotropies on large scales better than the concordance model
with infinite volume. For most observer positions it matches the temperature
correlation function even slightly better than the well studied 3-torus
topology
Effect of pyridoxal deficiency on biotin content of N. sitophila
Effect of pyridoxal deficiency on biotin content of N. sitophil
Effect of biotin on lipid content of Neurospora crassa
Effect of biotin on lipid conten
Numerical computation of Maass waveforms and an application to cosmology
We compute numerically eigenvalues and eigenfunctions of the Laplacian in a
three-dimensional hyperbolic space. Applying the results to cosmology, we
demonstrate that the methods learned in quantum chaos can be used in other
fields of research.Comment: A version of the paper with high resolution figures is available at
http://www.physik.uni-ulm.de/theo/qc/publications.htm
Permalloy-based carbon nanotube spin-valve
In this Letter we demonstrate that Permalloy (Py), a widely used Ni/Fe alloy,
forms contacts to carbon nanotubes (CNTs) that meet the requirements for the
injection and detection of spin-polarized currents in carbon-based spintronic
devices. We establish the material quality and magnetization properties of Py
strips in the shape of suitable electrical contacts and find a sharp
magnetization switching tunable by geometry in the anisotropic
magnetoresistance (AMR) of a single strip at cryogenic temperatures. In
addition, we show that Py contacts couple strongly to CNTs, comparable to Pd
contacts, thereby forming CNT quantum dots at low temperatures. These results
form the basis for a Py-based CNT spin-valve exhibiting very sharp resistance
switchings in the tunneling magnetoresistance, which directly correspond to the
magnetization reversals in the individual contacts observed in AMR experiments.Comment: 3 page
Hot pixel contamination in the CMB correlation function?
Recently, it was suggested that the map-making procedure, which is applied to
the time-ordered CMB data by the WMAP team, might be flawed by hot pixels. This
could lead to a bias in the pixels having an angular distance of about 141
degrees from hot pixels due to the differential measuring process of the
satellite WMAP. Here, the bias is confirmed, and the temperature two-point
correlation function C(theta) is reevaluated by excluding the affected pixels.
It is shown that the most significant effect occurs in C(theta) at the largest
angles near theta = 180 degrees. Furthermore, the corrected correlation
function C(theta) is applied to the cubic topology of the Universe, and it is
found that such a multi-connected universe matches the temperature correlation
better than the LCDM concordance model, provided the cubic length scale is
close to L=4 measured in units of the Hubble length
On the possibility for constraining cosmic topology from the celestial distribution of astronomical objects
We present a method to constrain cosmic topology from the distribution of
astronomical objects projected on the celestial sphere. This is an extension of
the 3D method introduced in Fujii & Yoshii (2011) that is to search for a pair
of pairs of observed objects (quadruplet) linked by a holonomy, i.e., the
method we present here is to search for a pair of celestial sphere -tuplets
for . We find, however, that this method is impractical to apply in
realistic situations due to the small signal to noise ratio. We conclude
therefore that it is unrealistic to constrain the topology of the Universe from
the celestial distribution, and the 3D catalogs are necessary for the purpose.Comment: 4 pages, 1 figure, accepted for publication in A&A (2011
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