3,450 research outputs found
Wheat and Grain Sorghum in Four-Year Rotations
Research on 4-year crop rotations with wheat and grain sorghum was initiated in 1996 at the Southwest Research-Extension Center near Tribune, Kansas. Rotations were wheat-wheat-sorghum-fallow (WWSF), wheat-sorghum-sorghum-fallow (WSSF), and continuous wheat (WW). Soil water at wheat planting averaged about 9 inches following sorghum, which is about 3 inches more than the average for the second wheat crop in a WWSF rotation. Soil water at sorghum planting was only about 1 inch less for the second sorghum crop compared with sorghum following wheat. Grain yield of recrop wheat averaged about 80% of the yield of wheat following sorghum. Grain yield of continuous wheat averaged about 65% of the yield of wheat grown in a 4-year rotation following sorghum. Wheat yields were similar following one or two sorghum crops. Similarly, average sorghum yields were the same following one or two wheat crops. Yield of the second sorghum crop in a WSSF rotation was only about 10% of the yield of the first sorghum crop in 2014, although the long-term average is about 65% of the yield of the first sorghum crop
The human ehrlichioses in the United States.
The emerging tick-borne zoonoses human monocytic ehrlichiosis (HME) and human granulocytic ehrlichiosis (HGE) are under reported in the United States. From 1986 through 1997, 1,223 cases (742 HME, 449 HGE, and 32 not ascribed to a specific ehrlichial agent) were reported by state health departments. HME was most commonly reported from southeastern and southcentral states, while HGE was most often reported from northeastern and upper midwestern states. The annual number of reported cases increased sharply, from 69 in 1994 to 364 in 1997, coincident with an increase in the number of states making these conditions notifiable. From 1986 through 1997, 827 probable and confirmed cases were diagnosed by serologic testing at the Centers for Disease Control and Prevention, although how many of these cases were also reported by states is not known. Improved national surveillance would provide a better assessment of the public health importance of ehrlichiosis
Re-entrant ferroelectricity in liquid crystals
The ferroelectric (Sm C) -- antiferroelectric (Sm C) -- reentrant
ferroelectric (re Sm C) phase temperature sequence was observed for system
with competing synclinic - anticlinic interactions. The basic properties of
this system are as follows (1) the Sm C phase is metastable in temperature
range of the Sm C stability (2) the double inversions of the helix
handedness at Sm C -- Sm C and Sm C% -- re-Sm C phase
transitions were found (3) the threshold electric field that is necessary to
induce synclinic ordering in the Sm C phase decreases near both Sm
C -- Sm C and Sm C -- re-Sm C phase boundaries, and it has
maximum in the middle of the Sm C stability region. All these properties
are properly described by simple Landau model that accounts for nearest
neighboring layer steric interactions and quadrupolar ordering only.Comment: 10 pages, 5 figures, submitted to PR
Herbicide Evaluation for Control of Kochia and Palmer Amaranth in Teff Grass
Eleven postemergence herbicide treatments were applied to teff grown for forage to evaluate Palmer amaranth and kochia control, as well as crop tolerance. Effective Palmer amaranth control was achieved with all herbicide treatments, while less than satisfactory kochia control was obtained with atrazine and Harmony. Clarity, 2,4-D, and Huskie applied alone appeared to control kochia, but kochia density was low in the plots. Had the kochia population been higher, similar efficacy ratings may have been attained. Huskie or atrazine caused the most injury to teff. The first harvest suggests these herbicides reduced forage yield to less than 3,000 lb/a
Assessment of the visibility impairment caused by the emissions from the proposed power plant at Boron, California
The current atmospheric conditions and visibility were modeled, and the effect of the power plant effluent was then added to determine its influence upon the prevailing visibility; the actual reduction in visibility being a function of meteorological conditions and observer-plume-target geometry. In the cases investigated, the perceptibility of a target was reduced by a minimum of 10 percent and a maximum of 100 percent. This significant visual impact would occur 40 days per year in the Edwards area with meteorological conditions such as to cause some visual impact 80 days per year
Energy Spectrum of the Electrons Accelerated by a Reconnection Electric Field: Exponential or Power Law?
The direct current (DC) electric field near the reconnection region has been
proposed as an effective mechanism to accelerate protons and electrons in solar
flares. A power-law energy spectrum was generally claimed in the simulations of
electron acceleration by the reconnection electric field. However in most of
the literature, the electric and magnetic fields were chosen independently. In
this paper, we perform test-particle simulations of electron acceleration in a
reconnecting magnetic field, where both the electric and magnetic fields are
adopted from numerical simulations of the MHD equations. It is found that the
accelerated electrons present a truncated power-law energy spectrum with an
exponential tail at high energies, which is analogous to the case of diffusive
shock acceleration. The influences of reconnection parameters on the spectral
feature are also investigated, such as the longitudinal and transverse
components of the magnetic field and the size of the current sheet. It is
suggested that the DC electric field alone might not be able to reproduce the
observed single or double power-law distributions.Comment: 18 pages, 6 figures, published in Ap
Negotiating sexuality and masculinity in school sport: An autoethnography
This autoethnography explores challenging and ethically sensitive issues around sexual orientation, sexual identity and masculinity in the context of school sport. Through storytelling, I aim to show how sometimes ambiguous encounters with heterosexism, homophobia and hegemonic masculinity through sport problematise identity development for young same-sex attracted males. By foregrounding personal embodied experience, I respond to an absence of stories of gay and bisexual experiences among males in physical education and school sport, in an effort to reduce a continuing sense of Otherness and difference regarding same-sex attracted males. I rely on the story itself to express the embodied forms of knowing that inhabit the experiences I describe, and resist a finalising interpretation of the story. Instead, I offer personal reflections on particular theoretical and methodological issues which relate to both the form and content of the story
Obliquity Tides on Hot Jupiters
Obliquity tides are a potentially important source of heat for extrasolar
planets on close-in orbits. Although tidal dissipation will usually reduce the
obliquity to zero, a nonzero obliquity can persist if the planet is in a
Cassini state, a resonance between spin precession and orbital precession.
Obliquity tides might be the cause of the anomalously large size of the
transiting planet HD 209458b.Comment: To appear in ApJ Letters [9 pages, 2 figures
The architecture of the hierarchical triple star KOI 928 from eclipse timing variations seen in Kepler photometry
We present a hierarchical triple star system (KIC 9140402) where a low mass
eclipsing binary orbits a more massive third star. The orbital period of the
binary (4.98829 Days) is determined by the eclipse times seen in photometry
from NASA's Kepler spacecraft. The periodically changing tidal field, due to
the eccentric orbit of the binary about the tertiary, causes a change in the
orbital period of the binary. The resulting eclipse timing variations provide
insight into the dynamics and architecture of this system and allow the
inference of the total mass of the binary ()
and the orbital parameters of the binary about the central star.Comment: Submitted to MNRAS Letters. Additional tables with eclipse times are
included here. The Kepler data that was used for the analysis of this system
(Q1 through Q6) will be available on MAST after June 27, 201
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