438 research outputs found
Scenario-Driven Crisis Management Planning: Efforts of the Tokai Netherlands Storm Surge and Flood Prone Area Committee
Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv
A Case of 48, XYY, +21
A 3 month-old boy with a karyotype of 48, XYY, + 21 is reported. The patient had the typical features of Down syndrome and normal male genitalia.
Analysis of Q- and R-banded chromosome heteromorphisms of the patient and the parents showed that two of the three chromosomes 21 in the patient originated as a result of failure of the paternal second meiotic division. Therefore both additional chromosomes in the patient resulted from nondisjunction at paternal meiosis II
Effective nonlocal kernels on Reaction-diffusion networks
A new method to derive an essential integral kernel from any given
reaction-diffusion network is proposed. Any network describing metabolites or
signals with arbitrary many factors can be reduced to a single or a simpler
system of integro-differential equations called "effective equation" including
the reduced integral kernel (called "effective kernel" ) in the convolution
type. As one typical example, the Mexican hat shaped kernel is theoretically
derived from two component activator-inhibitor systems. It is also shown that a
three component system with quite different appearance from activator-inhibitor
systems is reduced to an effective equation with the Mexican hat shaped kernel.
It means that the two different systems have essentially the same effective
equations and that they exhibit essentially the same spatial and temporal
patterns. Thus, we can identify two different systems with the understanding in
unified concept through the reduced effective kernels. Other two applications
of this method are also given: Applications to pigment patterns on skins (two
factors network with long range interaction) and waves of differentiation
(called proneural waves) in visual systems on brains (four factors network with
long range interaction). In the applications, we observe the reproduction of
the same spatial and temporal patterns as those appearing in pre-existing
models through the numerical simulations of the effective equations
Momentum-resolved resonant photoelectron spectroscopic study for 1T-TiSe: Observation of negative q in the Fano resonance due to inter-atomic interaction in the valence band
The remarkable properties of (1T-)TiSe among the transition metal
dichalcogenides have attracted the attention of many researchers due to its
peculiar behavior during the charge density wave (CDW) transition. Therefore,
it is highly desirable to study its electronic structure down to the atomic
orbitals. In the present research, we applied momentum-resolved resonant
photoelectron spectroscopy to study TiSe at the Ti2p-Ti3d absorption edge
by using a momentum microscope, which can simultaneously detect the electronic
states in a wide range. We have also used constant initial state
(CIS) spectroscopy and density functional theory (DFT) calculations to reveal
the hybridization between the Ti3d and Se4p orbitals within the valence band at
the Gamma point at room temperature. In addition, an interesting result comes
from our analysis of the CIS spectrum for the energy band located at a binding
energy of 2 eV at the M-point. This band, mainly composed of the Se4p orbital,
exhibited a Fano line profile at the Ti2p edge, with a negative value of the
parameter "". This is the first clear evidence of the inter-atomic
interaction during the valence band photoelectron emission process. This
behavior differs significantly from the standard resonant photoelectron
emission, which usually involves intra-atomic interactions. It also differs
from the multi-atom resonant photoelectron emission (MARPE) observed in the
core-level photoelectron emission, as we focus on the photoelectron emission
from the valence band in this research
Phonon-assisted indirect transitions in angle-resolved photoemission spectra of graphite and graphene
Indirect transitions of electrons in graphene and graphite are investigated by means of angle-resolved photoemission spectroscopy (ARPES) with several different incident photon energies and light polarizations. The theoretical calculations of the indirect transition for graphene and for a single crystal of graphite are compared with the experimental measurements for highly-oriented pyrolytic graphite and a single crystal of graphite. The dispersion relations for the transverse optical (TO) and the out-of-plane longitudinal acoustic (ZA) phonon modes of graphite and the TO phonon mode of graphene can be extracted from the inelastic ARPES intensity. We find that the TO phonon mode for k points along the Γ-K and K-M-K′ directions in the Brillouin zone can be observed in the ARPES spectra of graphite and graphene by using a photon energy ≈11.1 eV. The relevant mechanism in the ARPES process for this case is the resonant indirect transition. On the other hand, the ZA phonon mode of graphite can be observed by using a photon energy ≈6.3 eV through a nonresonant indirect transition, while the ZA phonon mode of graphene within the same mechanism should not be observed.National Science Foundation (U.S.) (Grant No. DMR- 1507806
Lithium production on a low-mass secondary in a black hole soft X-ray transient
We examine production of Li on the surface of a low-mass secondary in a black
hole soft X-ray transient (BHSXT) through the spallation of CNO nuclei by
neutrons which are ejected from a hot (> 10 MeV) advection-dominated accretion
flow (ADAF) around the black hole. Using updated binary parameters, cross
sections of neutron-induced spallation reactions, and mass accretion rates in
ADAF derived from the spectrum fitting of multi-wavelength observations of
quiescent BHSXTs, we obtain the equilibrium abundances of Li by equating the
production rate of Li and the mass transfer rate through accretion to the black
hole. The resulting abundances are found to be in good agreement with the
observed values in seven BHSXTs. We note that the abundances vary in a
timescale longer than a few months in our model. Moreover, the isotopic ratio
Li6/Li7 is calculated to be about 0.7--0.8 on the secondaries, which is much
higher than the ratio measured in meteorites. Detection of such a high value is
favorable to the production of Li via spallation and the existence of a hot
accretion flow, rather than an accretion disk corona system in quiescent BHSXT.Comment: 4 pages, 3 figures, and 2 tables, submitted to Astrophyscal Jounal
Letter
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