657 research outputs found
Intra-valley topographical control of nocturnal valley winds
July 1987.Bibliography: leaves 99-101.Sponsored by the National Science Foundation ATM-830428.Sponsored by the Colorado State University Agricultural Experiment Station
One gene versus two: A regional study on the efficacy of single gene versus pyramided resistance for soybean aphid management
Citation: McCarville, M. T., M. E. O’Neal, B. D. Potter, K. J. Tilmon, E. M. Cullen, B. P. McCornack, J. F. Tooker, and D. A. Prischmann-Voldseth. 2014. “One Gene Versus Two: A Regional Study on the Efficacy of Single Gene Versus Pyramided Resistance for Soybean Aphid Management.” Journal of Economic Entomology 107 (4): 1680–87. https://doi.org/10.1603/EC14047.The soybean aphid (Aphis glycines Matsumura) is a threat to soybean production in the Midwestern United States. Varieties containing the Rag1 soybean aphid resistance gene have been released with limited success in reducing aphid populations. Furthermore, virulent biotypes occur within North America and challenge the durability of single-gene resistance. Pyramiding resistance genes has the potential to improve aphid population suppression and increase resistance gene durability. Our goal was to determine if a pyramid could provide improved aphid population suppression across a wide range of environments.Weconducted a small-plot Þeld experiment across seven states and three years. We compared soybean near-isolines for the Rag1 or Rag2 gene, and a pyramid
line containing both genes for their ability to decrease aphid pressure and protect yield compared with a susceptible line. These lines were evaluated both with and without a neonicitinoid seed treatment. All aphid-resistant lines signiÞcantly decreased aphid pressure at all locations but one. The pyramid line experienced lower aphid pressure than both single-gene lines at eight of 23 location-years. Soybean aphids signiÞcantly reduced soybean yield for the susceptible line by 14% and for both single-gene lines
by 5%; however, no signiÞcant yield decrease was observed for the pyramid line. The neonicitinoid seed treatment reduced plant exposure to aphids across all soybean lines, but did not provide signiÞcant yield protection for any of the lines. These results demonstrate that pyramiding resistance genes can provide sufÞcient and consistent yield protection from soybean aphid in North America
Development of Temperature and Humidity-Based Indicators for Diagnosing Problems in Low Tonnage, Split System Air Conditioners
This paper presents results of a survey of the
literature and identifies the most common degraded
conditions associated with low-tonnage air
conditioners. Other laboratory studies as well as
marketed diagnostic systems are also summarized. A
procedure for identification of useful, low-cost
temperature-based indicators of degraded conditions
has been developed at the Energy Systems
Laboratory, Texas A&M University in College
Station, TX under contract to Honeywell. This paper
presents the methodology used to identify the
temperature-based indicators for the most common
degraded conditions gleaned from the literature
Surface Geometric and Electronic Structure of BaFe2As2(001)
BaFe2As2 exhibits properties characteristic of the parent compounds of the
newly discovered iron (Fe)-based high-TC superconductors. By combining the real
space imaging of scanning tunneling microscopy/spectroscopy (STM/S) with
momentum space quantitative Low Energy Electron Diffraction (LEED) we have
identified the surface plane of cleaved BaFe2As2 crystals as the As terminated
Fe-As layer - the plane where superconductivity occurs. LEED and STM/S data on
the BaFe2As2(001) surface indicate an ordered arsenic (As) - terminated
metallic surface without reconstruction or lattice distortion. It is surprising
that the STM images the different Fe-As orbitals associated with the
orthorhombic structure, not the As atoms in the surface plane.Comment: 12 pages, 4 figure
One Year of Alendronate Treatment Lowers Microstructural Stresses Associated with Trabecular Microdamage Initiation
Alendronate, an anti-remodeling agent, is commonly used to treat patients suffering from osteoporosis by increasing bone mineral density. Though fracture risk is lowered, an increase in microdamage accumulation has been documented in patients receiving alendronate, leading to questions about the potentially detrimental effects of remodeling suppression on the local tissue (material) properties. In this study, trabecular bone cores from the distal femur of beagle dogs treated for one year with alendronate, at doses scaled by weight to approximate osteoporotic and Paget's disease treatment doses in humans, were subjected to uniaxial compression to induce microdamage. Tissue level von Mises stresses were computed for alendronate-treated and non-treated controls using finite element analysis and correlated to microdamage morphology. Using a modified version of the Moore and Gibson classification for damage morphology, we determined that the von Mises stress for trabeculae exhibiting severe and linear microcrack patterns was decreased by approximately 25% in samples treated with alendronate compared with non-treated controls (p<0.01), whereas there was no reduction in the von Mises stress state for diffuse microdamage formation. Furthermore, an examination of the architectural and structural characteristics of damaged trabeculae demonstrated that severely damaged trabeculae were thinner, more aligned with the loading axis, and less mineralized than undamaged trabeculae in alendronate-treated samples (p<0.01). Similar relationships with damage morphology were found only with trabecular orientation in vehicle-treated control dogs. These results indicate that changes in bone's architecture and matrix properties associated with one year of alendronate administration reduce trabecular bone's ability to resist the formation of loading-induced severe and linear microcracks, both of which dissipate less energy prior to fracture than does diffuse damage
Analysis of the MOST light curve of the heavily spotted K2IV component of the single-line spectroscopic binary II Pegasi
Continuous photometric observations of the visible component of the
single-line, K2IV spectroscopic binary II Peg carried out by the MOST satellite
during 31 consecutive days in 2008 have been analyzed. On top of spot-induced
brightness modulation, eleven flares were detected of three distinct types
characterized by different values of rise, decay and duration times. The flares
showed a preference for occurrence at rotation phases when the most spotted
hemisphere is directed to the observer, confirming previous similar reports. An
attempt to detect a grazing primary minimum caused by the secondary component
transiting in front of the visible star gave a negative result. The brightness
variability caused by spots has been interpreted within a cold spot model. An
assumption of differential rotation of the primary component gave a better fit
to the light curve than a solid-body rotation model.Comment: Accepteed to MNRA
Characterisation of the effects of mutation of the caldesmon sequence 691glu-trp-leu-thr-lys-thr696 to pro-gly-his-tyr-asn-asn on caldesmon-calmodulin interaction
AbstractWe have investigated the functional properties of a mutant (Cg1) derived from the C-terminal 99 amino acids of chicken caldesmon, 658–756 (658C) where the sequence 691glu-trp-leu-thr-lys-thr696 is changed to pro-gly-his-tyr-asn-asn. Cg1 bound Ca2+-calmodulin with (1/7)th of the affinity as compared to 658C or whole caldesmon. NMR titrations indicate that the contacts of Ca2+-calmodulin with the Trp-722 region of the peptide are retained but that those at the mutated site are lost. Most importantly Ca2+-calmodulin is not able to reverse the Cg1-induced inhibition. We conclude that the interaction of calmodulin with this caldesmon sequence is crucial for the reversal of caldesmon inhibition of actin-tropomyosin activation of myosin ATPase. The results are interpreted in terms of multi-site attachment of actin and Ca2+-calmodulin to overlapping sequences in caldesmon domain 4b
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