4,584 research outputs found
Research Notes : Influence of maturity date on the oil content of soybeans with genetically altered fatty acid composition
sed oleic acid percentage has been proven successful in decreasing the percentage of linolenic acid in soybean oil (Burton et al., 1983). In the first four cycles of selection, the percentage of oleic acid in the seed oil increased linearly at an average rate of 1.6 + 0.2% per cycle whereas linoleic and linolenic acid percentages showed linear decreases. Four additional cycles of selection for increased oleic acid and two cycles for decreased oleic acid levels are currently being evaluated in a wide range of environ-ments
Inoculation Experiments with Gymnosporangium macropus Lk.
The family of true rusts, Uredineae, is very interesting to the mycologist and important to the agriculturist. It contains about twenty-seven genera and a multitude of species, all of which are strict parasites, living within the tissues of their hosts. Several of the species produce destructive diseases in cultivated plants; as examples note the rust of wheat, oats and other grasses (Puccinia graminis, Pers.), blackberry rust (Caeoma luminatum, Schw.), and carnation rust (Uromyces caryophyllinus [Schrank], Schroeter). Thus far all attempts to cultivate the rusts upon artificial media have failed
Research Notes : Inheritance of fatty acid composition in soybean seed oil
While it has been demonstrated that the fatty acid composition of soybean oil can be changed by recurrent selection (Wilson et al., 1981), there is little information about the genetic control of oil biosynthesis in soybean seeds. In some species, such as rape (Downey and Harvey, 1963), safflower (Yermanos et al., 1967), and flax (Yermanos and Knowles, 1962), the male parent has a significant effect on the fatty acid composition of oil from F1 hybrid seeds. In corn (Jellum, 1966) and soybeans (Brim et al., 1968), the male parent has almost no effect on oil composition of F1 hybrid seeds
Parity-Violating Interaction Effects in the np System
We investigate parity-violating observables in the np system, including the
longitudinal asymmetry and neutron-spin rotation in np elastic scattering, the
photon asymmetry in np radiative capture, and the asymmetries in deuteron
photo-disintegration d(gamma,n)p in the threshold region and
electro-disintegration d(e,e`)np in quasi-elastic kinematics. To have an
estimate of the model dependence for the various predictions, a number of
different, latest-generation strong-interaction potentials--Argonne v18, Bonn
2000, and Nijmegen I--are used in combination with a weak-interaction potential
consisting of pi-, rho-, and omega-meson exchanges--the model known as DDH. The
complete bound and scattering problems in the presence of parity-conserving,
including electromagnetic, and parity-violating potentials is solved in both
configuration and momentum space. The issue of electromagnetic current
conservation is examined carefully. We find large cancellations between the
asymmetries induced by the parity-violating interactions and those arising from
the associated pion-exchange currents. In the np capture, the model dependence
is nevertheless quite small, because of constraints arising through the Siegert
evaluation of the relevant E1 matrix elements. In quasi-elastic electron
scattering these processes are found to be insignificant compared to the
asymmetry produced by gamma-Z interference on individual nucleons.Comment: 65 pages, 26 figures, submitted to PR
Cumulative and Differential Effects of Early Child Care and Middle Childhood Out-of-School Time on Adolescent Functioning.
Effects associated with early child care and out-of-school time (OST) during middle childhood were examined in a large sample of U.S. adolescents (N = 958). Both higher quality early child care AND more epochs of organized activities (afterschool programs and extracurricular activities) during middle childhood were linked to higher academic achievement at age 15. Differential associations were found in the behavioral domain. Higher quality early child care was associated with fewer externalizing problems, whereas more hours of early child care was linked to greater impulsivity. More epochs of organized activities was associated with greater social confidence. Relations between early child care and adolescent outcomes were not mediated or moderated by OST arrangements in middle childhood, consistent with independent, additive relations of these nonfamilial settings
Development and exploratory cluster-randomised opportunistic trial of a theory-based intervention to enhance physical activity among adolescents
Peer reviewedPostprin
Kinetics of isothermal and non-isothermal precipitation in an Al-6at%Si alloy
A novel theory which describes the progress of a thermally activated reaction under isothermal and linear heating conditions is presented. It incorporates nucleation, growth and impingement and takes account of temperaturedependent solubility. The model generally fits very well to isothermal calorimetry and differential scanning calorimetry data on precipitation in an Al-6 at.% Si alloy. Analysis of the data shows that two processes occur in this precipitation reaction: growth of large Si particles and growth of pre-existing small nuclei. Determination of the sizes of Si precipitates by transmission electron microscopy indicates that interfacial energy contributions are small and have a negligible influence on solubilit
Genetic trends in winter wheat yield and test weight under dual-purpose and grain-only management systems
Wheat (Triticum aestivum L.) cultivars of the southern Great Plains are traditionally bred in environments managed for grain production only but are commonly grown for the dual-purpose of producing winter forage and grain from the same crop. To what extent grain yield and test weight are consistently expressed in those environments requires investigation relative to long-term attempts to improve them genetically. A historical set of hard red winter (HRW) wheat cultivars was evaluated under grain-only and dual-purpose management systems to compare their agronomic performance and derived estimates of genetic progress. Separate experiments were established for each system featuring whole-plot treatments of a foliar fungicide and split-plot treatments of 12 cultivars. The study was conducted for 3 yr at the Wheat Pasture Res. Ctr. near Marshall, OK. Dual-purpose experiments were generally grazed from November through February. Yield in the grain-only system improved 18.8 kg ha^-1 yr^-1, equivalent to 1.3% of the mean yield for Turkey. The rate of progress in the dual-purpose system was significantly lower at 11.3 kg ha^-1 yr^-1, equivalent to 0.9% of the mean for Turkey. Management for grazing had a more profound influence on estimates of yield improvement than did management for disease protection. Linear trends in test weight were not evident under either system, nor were cultivar differences influenced by management system consistently across years. Breeding practices should emphasize selection for grain yield in both environments if future progress is to be maximized in both.Peer reviewedPlant and Soil SciencesAnimal Scienc
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