400 research outputs found
Evaluation and Development of Blackbird Repellents for Agricultural Applications
We evaluated several registered fungicides and insecticides, and several natural compounds as candidate blackbird repellents for protecting agricultural production. We tested more than 750 red-winged blackbirds at the National Wildlife Research Center’s outdoor animal research facility in Fort Collins, CO to evaluate (1) their preference for treated versus untreated rice and sunflower seeds and (2) their consumption of seeds treated with varying concentrations of candidate repellents. Concentrations were varied between 10% and 200% of labeled application rates. With few exceptions, blackbirds discriminated between untreated seeds and seeds treated with one of the candidate repellents. We observed greatest repellency with caffeine + sodium benzoate, GWN-4770, Lorsban, and Tilt. Additional lab efficacy tests are planned for anthraquinone seed treatments, Flock Buster repellent, and Cobalt insecticide. Field residue and efficacy tests are also needed to evaluate and develop promising foliar repellents for protection of ripening crops
Evaluation and Development of Blackbird Repellents for Agricultural Applications
We evaluated several registered fungicides and insecticides, and several natural compounds as candidate blackbird repellents for protecting agricultural production. We tested more than 750 red-winged blackbirds at the National Wildlife Research Center’s outdoor animal research facility in Fort Collins, CO to evaluate (1) their preference for treated versus untreated rice and sunflower seeds and (2) their consumption of seeds treated with varying concentrations of candidate repellents. Concentrations were varied between 10% and 200% of labeled application rates. With few exceptions, blackbirds discriminated between untreated seeds and seeds treated with one of the candidate repellents. We observed greatest repellency with caffeine + sodium benzoate, GWN-4770, Lorsban, and Tilt. Additional lab efficacy tests are planned for anthraquinone seed treatments, Flock Buster repellent, and Cobalt insecticide. Field residue and efficacy tests are also needed to evaluate and develop promising foliar repellents for protection of ripening crops
The Northwest Tropical Atlantic Station (NTAS) : NTAS-1 mooring deployment cruise report
A surface mooring outfitted for meteorological and oceanographic measurement was deployed near 14°50'N, 51°00'W in the
northwest tropical Atlantic on 30 March 2001. This was the initial deployment of the Northwest Tropical Atlantic Station (NTAS)
project for air–sea flux measurement. These observations will be used to investigate air–sea interaction processes related to climate
variability. The deployment was done on R/V Oceanus Cruise 365, Leg 5 by the Upper Ocean Processes Group (UOP) of the
Woods Hole Oceanographic Institution. The 3-meter discus buoy was outfitted with two Air–Sea Interaction Meteorology
(ASIMET) systems. Each system measures, records, and transmits via Argos satellite the surface meteorological variables necessary
to compute air–sea fluxes of heat, moisture and momentum. The upper 120 m of the mooring line was outfitted with oceanographic
sensors for the measurement of temperature and velocity. This report describes the initial deployment of the NTAS mooring
(NTAS-1), including some of the pre-cruise buoy preparations and post cruise data comparisons.Funding was provided by the National Oceanic and Atmospheric Administration (NOAA) through the
Cooperative Institute for Climate and Ocean Research (CICOR) under Grant No. NA87RJ0445
DDFT calibration and investigation of an anisotropic phase-field crystal model
The anisotropic phase-field crystal model recently proposed and used by
Prieler et al. [J. Phys.: Condens. Matter 21, 464110 (2009)] is derived from
microscopic density functional theory for anisotropic particles with fixed
orientation. Further its morphology diagram is explored. In particular we
investigated the influence of anisotropy and undercooling on the process of
nucleation and microstructure formation from atomic to the microscale. To that
end numerical simulations were performed varying those dimensionless parameters
which represent anisotropy and undercooling in our anisotropic phase-field
crystal (APFC) model. The results from these numerical simulations are
summarized in terms of a morphology diagram of the stable state phase. These
stable phases are also investigated with respect to their kinetics and
characteristic morphological features.Comment: It contain 13 pages and total of 7 figure
Killing tensors in pp-wave spacetimes
The formal solution of the second order Killing tensor equations for the
general pp-wave spacetime is given. The Killing tensor equations are integrated
fully for some specific pp-wave spacetimes. In particular, the complete
solution is given for the conformally flat plane wave spacetimes and we find
that irreducible Killing tensors arise for specific classes. The maximum number
of independent irreducible Killing tensors admitted by a conformally flat plane
wave spacetime is shown to be six. It is shown that every pp-wave spacetime
that admits an homothety will admit a Killing tensor of Koutras type and, with
the exception of the singular scale-invariant plane wave spacetimes, this
Killing tensor is irreducible.Comment: 18 page
CLIVAR Mode Water Dynamics Experiment (CLIMODE) fall 2006 R/V Oceanus voyage 434 November 16, 2006–December 3, 2006
CLIMODE (CLIVAR Mode Water Dynamic Experiment) is a research program designed to
understand and quantify the processes responsible for the formation and dissipation of North
Atlantic subtropical mode water, also called Eighteen Degree Water (EDW). Among these
processes, the amount of buoyancy loss at the ocean-atmosphere interface is still uncertain and
needs to be accurately quantified.
In November 2006, cruise 434 onboard R/V Oceanus traveled in the region of the separated Gulf
Stream and its recirculation, where intense oceanic heat loss to the atmosphere in the winter is
believed to trigger the formation of EDW. During this cruise, the surface mooring F that was
anchored in the core of the Gulf Stream was replaced by a new one, as well as two subsurface
moorings C and D located on the southeastern edge of the stream. Surface drifters, ARGO and
bobbers RAFOS floats were deployed, CTD profiles and water samples were also carried out.
This array of instruments will permit a characterization of EDW with high spatial and temporal
resolutions and accurate in-situ measurements of air-sea fluxes in the EDW formation region.
The present report documents this cruise, the methods and locations for the deployments of
instruments and some evaluation of the measurements from these instruments.Funding was provided by the National Science Foundation under contract No. OCE04-2453
The Northwest Tropical Atlantic Station (NTAS) : NTAS-2 mooring turnaround cruise report
The Northwest Tropical Atlantic Station (NTAS) was established to address the
need for accurate air-sea flux estimates and upper ocean measurements in a region with
strong sea surface temperature anomalies and the likelihood of significant local air–sea
interaction on interannual to decadal timescales. The approach is to maintain a surface
mooring outfitted for meteorological and oceanographic measurements at a site near
15°N, 51°W by successive mooring turnarounds. These observations will be used to
investigate air–sea interaction processes related to climate variability.
Deployment of the first NTAS mooring (NTAS-1) at 14°50′ N, 51°00′ W on 30
March 2001 was documented in a previous report (Plueddemann et al., 2001). This report
documents recovery of the NTAS-1 mooring and deployment of the NTAS-2 mooring at
the same site. Both moorings used 3-meter discus buoys as the surface element. These
buoys were outfitted with two Air–Sea Interaction Meteorology (ASIMET) systems.
Each system measures, records, and transmits via Argos satellite the surface
meteorological variables necessary to compute air–sea fluxes of heat, moisture and
momentum. The upper 120 m of the NTAS-1 mooring line, and the upper 150 m of the
NTAS-2 mooring line, were outfitted with oceanographic sensors for the measurement of
temperature and velocity.
The mooring turnaround was done on the NOAA Ship Ronald H. Brown, Cruise
RB-02-02, by the Upper Ocean Processes Group of the Woods Hole Oceanographic
Institution. The cruise took place between 2 and 8 March 2002. A SeaBeam bathymetry
survey of the site was done first, followed by deployment of the NTAS-2 mooring on 4
March at approximately 14°44.3′ N, 50°56.8′ W in 5043 m of water. A 24-hour
intercomparison period followed, after which the NTAS-1 mooring was recovered. This
report describes these operations, as well as some of the pre-cruise buoy preparations.Funding was provided by the National Oceanic and Atmospheric Administration and the Cooperative Institute for Climate and Ocean Research (CICOR) under Grant No. NA17RJ1223
Hypersurface homogeneous locally rotationally symmetric spacetimes admitting conformal symmetries
All hypersurface homogeneous locally rotationally symmetric spacetimes which
admit conformal symmetries are determined and the symmetry vectors are given
explicitly. It is shown that these spacetimes must be considered in two sets.
One set containing Ellis Class II and the other containing Ellis Class I, III
LRS spacetimes. The determination of the conformal algebra in the first set is
achieved by systematizing and completing results on the determination of CKVs
in 2+2 decomposable spacetimes. In the second set new methods are developed.
The results are applied to obtain the classification of the conformal algebra
of all static LRS spacetimes in terms of geometrical variables. Furthermore all
perfect fluid nontilted LRS spacetimes which admit proper conformal symmetries
are determined and the physical properties some of them are discussed.Comment: 15 pages; to appear in Classical Quantum Gravity; some misprints in
Tables 3,5 and in section 4 correcte
Nonlinear evolution of dark matter and dark energy in the Chaplygin-gas cosmology
The hypothesis that dark matter and dark energy are unified through the
Chaplygin gas is reexamined. Using generalizations of the spherical model which
incorporate effects of the acoustic horizon we show that an initially
perturbative Chaplygin gas evolves into a mixed system containing cold dark
matter-like gravitational condensate.Comment: 11 pages, 3 figures, substantial revision, title changed, content
changed, added references, to appear in JCA
Off Mass Shell Effects in Hadron Electric Dipole Moments
We note that off the quark mass shell the operators
and , both of which reduce to
in the non-relativistic limit, are no longer
identical. In this paper we explore the effects of this difference in the
contribution of these quark electric moments to hadronic electric moments.Comment: 21 pages, 1 figure, Revtex, uses psfi
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