23,057 research outputs found
Ammonia oxidation is not required for growth of Group 1.1c soil Thaumarchaeota
© FEMS 2015. FUNDING EBW is funded by Centre for Genome Enabled Biology and Medicine, University of Aberdeen.Peer reviewedPublisher PD
Keck Studies of M31's Stellar Halo
We present Keck 10-meter/LRIS spectra of candidate red giants in the halo of
M31, located at a projected radius of R=19kpc on the minor axis. These
spectroscopic targets have been selected using a combination of UBRI-based and
morphological screening to eliminate background galaxies. Radial velocity
measurements are used to separate M31 halo giants from foreground Milky Way
dwarf stars, M31 disk stars, and residual background galaxies. The metallicity
of each M31 halo giant is measured using standard photometric and spectroscopic
techniques, the latter based on the strength of the CaII triplet. The various
[Fe/H] estimates are in rough agreement with one another. The data reveal a
large spread (>2dex) in [Fe/H] in M31's halo; there is no strong radial [Fe/H]
gradient. LRIS and HIRES spectra are also presented for red giants in five
dwarf spheroidal satellites of M31: AndI, AndIII, AndV, AndVI, and AndVII.
There appears to be a significant metallicity spread in AndVI and possibly in
AndI. The new radial velocity data on these outer dwarfs are used to constrain
the total mass of M31: the best estimate is under 10^(12)Msun, somewhat less
than the best estimate for the Milky Way.Comment: 12 pages, 7 figures, Proceedings of SPIE Conference: Discoveries and
Research Prospects with 8-10 Meter Class Telescopes (Munich March 2000
A universal platform for magnetostriction measurements in thin films
We present a universal nanomechanical sensing platform for the investigation
of magnetostriction in thin films. It is based on a doubly-clamped silicon
nitride nanobeam resonator covered with a thin magnetostrictive film. Changing
the magnetization direction within the film plane by an applied magnetic field
generates a magnetostrictive stress and thus changes the resonance frequency of
the nanobeam. A measurement of the resulting resonance frequency shift, e.g. by
optical interferometry, allows to quantitatively determine the magnetostriction
constants of the thin film. We use this method to determine the
magnetostriction constants of a 10nm thick polycrystalline cobalt film, showing
very good agreement with literature values. The presented technique can be
useful in particular for the precise measurement of magnetostriction in a
variety of (conducting and insulating) thin films, which can be deposited by
e.g. electron beam deposition, thermal evaporation or sputtering
Spin transport and spin dephasing in zinc oxide
The wide bandgap semiconductor ZnO is interesting for spintronic applications
because of its small spin-orbit coupling implying a large spin coherence
length. Utilizing vertical spin valve devices with ferromagnetic electrodes
(TiN/Co/ZnO/Ni/Au), we study the spin-polarized transport across ZnO in
all-electrical experiments. The measured magnetoresistance agrees well with the
prediction of a two spin channel model with spin-dependent interface
resistance. Fitting the data yields spin diffusion lengths of 10.8nm (2K),
10.7nm (10K), and 6.2nm (200K) in ZnO, corresponding to spin lifetimes of 2.6ns
(2K), 2.0ns (10K), and 31ps (200K).Comment: 7 pages, 5 figures; supplemental material adde
Pendampingan Pengelolaan Sampah Berbasis Komunitas Posyandu Kartinikelurahan Ngaliyan - Kota Semarang
The objectives of this empowerment to the strengthening of environmental awareness according to the principles of conservation to provide guidance to residents of RT 13 / RW 06 Sub Ngaliyan through knowledge transfer include matters related to the management and processing of kitchen waste, increase the participation of community members, and strengthening to the community as a pioneer of environmental care. Activity methods consistent measures of community assistance through: socialization, practice, and mentoring as well as to monitor the success of the activities. Kitchen waste separation has been carried out by members of the community according to type, namely: assortment of vegetables, plastic, leftover food and other waste disposed in the trash that has been owned by each member. Participatory members in environmental management in accordance prinsi-conservation principles were shared by all (100%) members, this condition is relatively easy to do because of the community living in housing that is built. The practice of processing kitchen waste into compost is done by three teams consisting of 5-7 family. Results compost is used to fertilize ornamental plants and to fertilize plants roadside South Karonsih. Indicators of success are known activities of enthusiastic participants in the discussion that demonstrate mastery of the material. In addition it is nevertheless manage and process waste even without assistance
L\'{e}vy-based growth models
In the present paper, we give a condensed review, for the nonspecialist
reader, of a new modelling framework for spatio-temporal processes, based on
L\'{e}vy theory. We show the potential of the approach in stochastic geometry
and spatial statistics by studying L\'{e}vy-based growth modelling of planar
objects. The growth models considered are spatio-temporal stochastic processes
on the circle. As a by product, flexible new models for space--time covariance
functions on the circle are provided. An application of the L\'{e}vy-based
growth models to tumour growth is discussed.Comment: Published in at http://dx.doi.org/10.3150/07-BEJ6130 the Bernoulli
(http://isi.cbs.nl/bernoulli/) by the International Statistical
Institute/Bernoulli Society (http://isi.cbs.nl/BS/bshome.htm
Bloch oscillations of Bose-Einstein condensates: Quantum counterpart of dynamical instability
We study the Bloch dynamics of a quasi one-dimensional Bose-Einstein
condensate of cold atoms in a tilted optical lattice modeled by a Hamiltonian
of Bose-Hubbard type: The corresponding mean-field system described by a
discrete nonlinear Schr\"odinger equation can show a dynamical (or modulation)
instability due to chaotic dynamics and equipartition over the quasimomentum
modes. It is shown, that these phenomena are related to a depletion of the
Floquet-Bogoliubov states and a decoherence of the condensate in the
many-particle description. Three different types of dynamics are distinguished:
(i) decaying oscillations in the region of dynamical instability, and (ii)
persisting Bloch oscillations or (iii) periodic decay and revivals in the
region of stability.Comment: 12 pages, 14 figure
Grafting melons onto potential cucumis spp. rootstocks
Cucumís
melo
is
an
economically
importar]t
crop.
Its
culture
is
hampered
by
differen
t
types
of
soil
stresses.
Grafting
melons
onto
different
resistant
cucurbits
belonging
to
the
genera,
Cucurbíta,
Lagenaría,
Luffa,
etc.
have
been
successfully
used
to
avoid
these
problems.
However,
me
Ion
quality
has
been
nega.tively
modified
as
a
consequence
of
grafting.
In
general,
variation
in
fruit
shape,
seed
cavity
and
sugar
content
have
been
observed.
The
use
of
rootstocks
more
genetically
c\oser
to
the
melon
scions
could
be
useful
to
obtain
fru
i
ts
with
better
quality
from
melon
grafted
plantsPostprint (published version
Results on the nucleon spin structure
SMC performed an investigation of the spin structure of the nucleon by
measuring deep inelastic scattering of polarised muons off polarised protons
and deuterons. A summary of the results for spin structure functions and sum
rules is given.Comment: 8 pages, LaTeX, Talk given at the Workshop on "Symmetry and Spin -
PRAHA98", Prag, September 1998. Proceedings to be published by Czech. Journ.
Phy
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