A comparison of hydroponic and conventional methods of vegetable transplant production

Traditional float bed culture, common in the production of tobacco transplants, was used to investigate the potential for hydroponic transplant production of peppers and cabbage. Experiments were conducted in the summer and fall, 1998 at The University of Tennessee Agricultural Experiment Station, Knoxville, Tennessee. Two varieties of peppers, \u27King Arthur’ bell and \u27Grande\u27 Jalapeno, and the cabbage variety \u27Charmant\u27 were seeded independently in 128 cell Styrofoam trays in conventional growing media. Pepper trials consisted of a conventional hydroponic treatment, a heated hydroponic treatment and a conventional treatment. Cabbage trials consisted of four treatments; aerated hydroponic, aerated- shaded (30%), and non-aerated hydroponic under both shaded and non-shaded conditions. Transplant growth, vigor, and development were monitored in both experiments and total yield and quality of yield were determined after transplant. Temperature enhanced the germination rate of pepper with the heated treatment resulting in the fastest germination for the \u27Grande\u27 jalapeno variety. Pepper plants in both the heated and conventional hydroponic treatments grew faster and larger than those in the conventional treatment. Total mean fresh and dry weights of both root and shoot material were consistently greater for the hydroponic treatments, with the heated treatment showing the greatest positive trends in plant growth and development. Pepper transplants from all treatments survived equally well in the field. No differences were observed in days until flowering, first fruit set, early yield, total yield or in fruit quality. A significant difference in yield was observed between varieties with \u27Grande\u27 Jalapeno producing the greatest early and total yields. Cabbage transplants grew faster and were larger when grown in the aerated nutrient solution producing transplants that were taller, heavier and that had wider and longer leaves than in non-aerated treatments. Shading of aerated plants reduced shoot weight, leaf length and leaf width. Total plant stand in the field was less for both aerated treatments with the shade + aeration treatment producing the lowest percentage of surviving plants. There was no difference observed in total percentage of plants producing marketable heads or in marketable head weight. Yields were greatest in the non-aerated treatments with the full sun-aeration plants producing the greatest yield

Tracing magnetic separators and their dependence on IMF clock angle in global magnetospheric simulations

A new, efficient, and highly accurate method for tracing magnetic separators in global magnetospheric simulations with arbitrary clock angle is presented. The technique is to begin at a magnetic null and iteratively march along the separator by finding where four magnetic topologies meet on a spherical surface. The technique is verified using exact solutions for separators resulting from an analytic magnetic field model that superposes dipolar and uniform magnetic fields. Global resistive magnetohydrodynamic simulations are performed using the three-dimensional BATS-R-US code with a uniform resistivity, in eight distinct simulations with interplanetary magnetic field (IMF) clock angles ranging from 0 (parallel) to 180 degrees (anti-parallel). Magnetic nulls and separators are found in the simulations, and it is shown that separators traced here are accurate for any clock angle, unlike the last closed field line on the Sun-Earth line that fails for southward IMF. Trends in magnetic null locations and the structure of magnetic separators as a function of clock angle are presented and compared with those from the analytic field model. There are many qualitative similarities between the two models, but quantitative differences are also noted. Dependence on solar wind density is briefly investigated.Comment: 10 pages, 10 figures, Presented at 2012 AGU Fall Meeting and 2013 Geospace Environment Modeling (GEM) Worksho

Asymmetric magnetic reconnection with a flow shear and applications to the magnetopause

We perform a theoretical and numerical study of anti-parallel 2D magnetic reconnection with asymmetries in the density and reconnecting magnetic field strength in addition to a bulk flow shear across the reconnection site in the plane of the reconnecting fields, which commonly occurs at planetary magnetospheres. We predict the speed at which an isolated X-line is convected by the flow, the reconnection rate, and the critical flow speed at which reconnection no longer takes place for arbitrary reconnecting magnetic field strengths, densities, and upstream flow speeds, and confirm the results with two-fluid numerical simulations. The predictions and simulation results counter the prevailing model of reconnection at Earth's dayside magnetopause which says reconnection occurs with a stationary X-line for sub-Alfvenic magnetosheath flow, reconnection occurs but the X-line convects for magnetosheath flows between the Alfven speed and double the Alfven speed, and reconnection does not occur for magnetosheath flows greater than double the Alfven speed. We find that X-line motion is governed by momentum conservation from the upstream flows, which are weighted differently in asymmetric systems, so the X-line convects for generic conditions including sub-Alfvenic upstream speeds. For the reconnection rate, while the cutoff condition for symmetric reconnection is that the difference in flows on the two sides of the reconnection site is twice the Alfven speed, we find asymmetries cause the cutoff speed for asymmetric reconnection to be higher than twice the asymmetric form of the Alfven speed. The results compare favorably with an observation of reconnection at Earth's polar cusps during a period of northward interplanetary magnetic field, where reconnection occurs despite the magnetosheath flow speed being more than twice the magnetosheath Alfven speed, the previously proposed suppression condition.Comment: 46 pages, 7 figures, abstract abridged here, accepted to Journal of Geophysical Research - Space Physic

IDENTIFICATION OF Acacia mangium PROVENANCES FOR SOLID-WOOD FOREST PLANTATIONS

Provenance trial is a planting test aimed at fi nding the best provenance for establishing forest plantations. Such best provenance depends on the type of fi nal harvest or yield expected. The objective of this research was to identify A. mangium provenances that were suitable for forest plantation producing solid woods for construction and furniture. A total of 225 samples of 15 provenances from Papua New Guinea and Australia were planted in three blocks in Parungpanjang, Bogor, West Java. The measured parameters included tree height, clear bole height, stem diameter, tree volume, stem form, branching habit, and crown form. Bi-plot analysis indicated that Kini WP, Keru Village WP, Derideri R. Morehead, and Claudia River were the best provenances in terms of productivity. Correspondence analysis showed that almost all provenances were equally good in stem form, but they varied in branching system as well as crown form. Provenances Kini WP, Keru Village WP, Kiriwo/Serisa WP, and Bimadebun Village possessed the better branching habit. In terms of crown form provenances Dimisi Village WP, Kiriwo/Serisa WP, and Derideri R. Morehead exhibited a good performance. In general, fi ve provenances, i.e. Kini WP, Keru Village WP, Derideri R. Morehead, Kiriwo/Serisa WP, and Claudia River were considered appropriate for seed sources supplying seeds for industrial plantation development intended to produce construction and furniture material

Paper Session I-C - Landsat-7 Managing the Transition

The Land Remote Sensing Policy Act of 1992, (Public Law PL102-555) recognized the importance of continuous collection and utilization of land remote se J?mg data from space. The Department of Defense (DoD) and the National Xmnautics and Space Administration (NASA) were responsible as the Landsat Program Management. The program proceeded with DOD developing the satellite and NASA developing the ground system. Each agency was for responsible its respective technical and budget requirements

Coordination pattern adaptability: energy cost of degenerate behaviors.

This study investigated behavioral adaptability, which could be defined as a blend between stability and flexibility of the limbs movement and their inter-limb coordination, when individuals received informational constraints. Seven expert breaststroke swimmers performed three 200-m in breaststroke at constant submaximal intensity. Each trial was performed randomly in a different coordination pattern: 'freely-chosen', 'maximal glide' and 'minimal glide'. Two underwater and four aerial cameras enabled 3D movement analysis in order to assess elbow and knee angles, elbow-knee pair coordination, intra-cyclic velocity variations of the center of mass, stroke rate and stroke length and inter-limb coordination. The energy cost of locomotion was calculated from gas exchanges and blood lactate concentration. The results showed significantly higher glide, intra-cyclic velocity variations and energy cost under 'maximal glide' compared to 'freely-chosen' instructional conditions, as well as higher reorganization of limb movement and inter-limb coordination (p<0.05). In the 'minimal glide' condition, the swimmers did not show significantly shorter glide and lower energy cost, but they exhibited significantly lower deceleration of the center of mass, as well as modified limb movement and inter-limb coordination (p<0.05). These results highlight that a variety of structural adaptations can functionally satisfy the task-goal