Root uptake of lipophilic zinc-rhamnolipid complexes

This study investigated the formation and plant uptake of lipophilic metal-rhamnolipid complexes. Monorhamnosyl and dirhamnosyl rhamnolipids formed lipophilic complexes with copper (Cu), manganese (Mn), and zinc (Zn). Rhamnolipids significantly increased Zn absorption by Brassica napus var. Pinnacle roots in 65Zn-spiked ice-cold solutions, compared with ZnSO4 alone. Therefore, rhamnolipid appeared to facilitate Zn absorption via a nonmetabolically mediated pathway. Synchrotron XRF and XAS showed that Zn was present in roots as Zn-phytate-like compounds when roots were treated with Zn-free solutions, ZnSO4, or Zn-EDTA. With rhamnolipid application, Zn was predominantly found in roots as the Zn-rhamnolipid complex. When applied to a calcareous soil, rhamnolipids increased dry matter production and Zn concentrations in durum (Triticum durum L. cv. Balcali-2000) and bread wheat (Triticum aestivum L. cv. BDME-10) shoots. Rhamnolipids either increased total plant uptake of Zn from the soil or increased Zn translocation by reducing the prevalence of insoluble Zn-phytate-like compounds in roots

Permeability of Corn, Soybeans, and Soft Red and White Winter Wheat as Affected by Bulk Density

Darcy’s law is a function of viscosity, permeability, and velocity and can be used to predict the airflow resistance in granular materials at low air velocities. Permeability also governs the magnitude of natural convection currents during periods of non-aerated grain storage. The permeability of corn, soybeans, soft white winter wheat, and soft red winter wheat were measured as a function of bulk density and moisture content. Air was passed through a column of grain and the flow rate and pressure drop measured. Bulk density and kernel density were also measured to determine the porosity of grain in the test column. Two filling methods were used to change the bulk density of grain by approximately 50 kg/m3, an increase of 7%. This resulted in a reduction in porosity of approximately 4 percentage points. However, permeability decreased by a maximum of 45%. Wheat had the lowest permeability (between 1.15 × 10-8 and 7.29 × 10-9 m2 or highest resistance coefficient between 1591 and 2510 Pa.s/m2, respectively, depending on bulk density and moisture content), while corn and soybeans were similar (permeability varied between 1.30 × 10-8 and 3.03 × 10-8 m2 or resistance coefficient between 1,408 and 604 Pa·s/m2, respectively). Experiments were conducted up to an air velocity of 0.0052 m/s that resulted in a Reynolds number of 2.5, which was slightly above the maximum air velocity expected during non-aerated grain storage. Nevertheless, Darcy’s law would be appropriate for predicting natural convection currents during non-aerated storage

Harvesting, Drying, and Storing Grain Sorghum

Grain sorghum (milo) has been successfully produced in many areas of Kentucky and can be grown in alternating years with soybeans to replace corn in a crop rotation cycle. For most of the past 20 years, it has ranked fourth in production of all grain crops grown in the state and was valued at $1.16 and$1.53 million in 1999 and 2000, respectively. Rotating milo with soybeans can help control soybean cyst nematodes and other pests that suppress yield. It can provide higher yields than corn in dry years, especially on sandy soils. The feed/energy value of milo is similar to corn, so it has been used successfully in balanced rations for beef, poultry, and swine and as a feedstock for ethanol production (Hamman et al., 2001). In fact, the 2002 Farm Bill (USDA, 2002) encourages an increase in the production of grain sorghum because of its use as an ethanol feedstock and the current national interest in reducing foreign oil imports

Clinical perspectives of emerging pathogens in bleeding disorders.

As a result of immunological and nucleic-acid screening of plasma donations for transfusion-transmissible viruses, and the incorporation of viral reduction processes during plasma fractionation, coagulation-factor concentrates (CFC) are now judged safe in terms of many known infectious agents, including hepatitis B and C viruses, HIV, and human T-cell lymphotropic virus. However, emerging pathogens could pose future threats, particularly those with blood-borne stages that are resistant to viral-inactivation steps in the manufacturing process, such as non-lipid-coated viruses. As outlined in this Review, better understanding of infectious diseases allows challenges from newly described agents of potential concern in the future to be anticipated, but the processes of zoonotic transmission and genetic selection or modification ensure that plasma-derived products will continue to be subject to infectious concerns. Manufacturers of plasma-derived CFC have addressed the issue of emerging infectious agents by developing recombinant products that limit the need for human plasma during production. Such recombinant products have extended the safety profile of their predecessors by ensuring that all reagents used for cell culture, purification steps, and stabilisation and storage buffers are completely independent of human plasma

Calculation of steady and unsteady pressures at supersonic speeds with CAP-TSD

A finite difference technique is used to solve the transonic small disturbance flow equation making use of shock capturing to treat wave discontinuities. Thus the nonlinear effects of thickness and angle of attack are considered. Such an approach is made feasible by the development of a new code called CAP-TSD (Computational Aeroelasticity Program - Transonic Small Disturbance), and is based on a fully implicit approximate factorization (AF) finite difference method to solve the time dependent transonic small disturbance equation. The application of the CAP-TSD code to the calculation of low to moderate supersonic steady and unsteady flows is presented. In particular, comparisons with exact linear theory solutions are made for steady and unsteady cases to evaluate shock capturing and other features of the current method. In addition, steady solutions obtained from an Euler code are used to evaluate the small disturbance aspects of the code. Steady and unsteady pressure comparisons are made with measurements for an F-15 wing model and for the RAE tailplane model

Effect of Moisture Content and Broken Kernels on the Bulk Density and Packing of Corn

Shelled yellow dent corn samples were conditioned to three moisture content levels (12%, 15%, and 18% w.b.) and mixed with a prescribed amount of broken corn particles of known size (geometric mean diameter of 1.0, 1.4, 2.0, 2.8, and 4.0 mm) and concentration (2.5%, 5.0%, and 7.5% by weight) levels. The initial bulk density and grain compaction under simulated overburden pressure tests were determined for each sample. Uniaxial compression tests were performed for seven vertical pressure levels (3.4, 6.9, 14, 28, 55, 110, and 165 kPa) with a minimum of three replications each. Tests were performed at two locations with identical apparatus, which was fully described by Thompson and Ross (1983). These devices used compressed air injected beneath a rubber diaphragm to apply vertical pressure uniaxially to a volume of granular material. Deflections of the grain mass were measured with a dial gauge and were used to calculate changes in bulk density and grain packing. Statistical models were tested for the initial bulk density and packing factor as a function of moisture content, broken corn particle size, and broken corn concentration level and their interactions. For clean corn, the initial bulk density was inversely affected by grain moisture while packing increased slightly with grain moisture. For corn mixed with fines, the initial bulk density decreased with grain moisture and the interaction of broken corn particle size and concentration but increased with the interaction of grain moisture and concentration of fines. Packing of corn mixed with fines increased slightly with grain moisture and broken corn concentration. For a given pressure, the predicted bulk density from the developed model was within 4% of the observed value, which was within the variation among test replications and may in fact represent observed differences in bulk density caused by bin loading methods that have been reported by other engineers. The results can improve predictions by WPACKING, the ASAE standard for estimating capacities of cylindrical grain storage structures

Spatial Variation of Protein, Oil, and Starch in Corn

Significant spatial yield variations are known to exist in cornfields with different soil types, topsoil depth, and other variables. Similarly, variations might also be found among the highly valued chemical components (oil, protein, and starch) in corn kernels due to local differences in soil type, fertility, acidity/pH, organic matter, etc. This study quantified the spatial variability of protein, oil, and starch content of corn from two conventional cornfields and two high-oil cornfields. Whole ears were harvested by hand from 20 to 40 randomly selected locations within each field. A differential global positioning system (DGPS) receiver recorded the location of each collection site. Samples were also collected from hauling vehicles with a segmented probe prior to transport from the field and from the grain stream as trucks were unloaded. A NIRSystems ® 6500 near-infrared reflectance instrument was used to measure the protein, oil, and starch concentration of each sample collected. Yield maps were plotted for each type of corn along with protein, oil, and starch variation. Results showed large variations between the conventional and high-oil cornfields. Slight variations were found between truck probe samples from the same field. Oil content was more variable than protein or starch. Probe samples appeared to provide the most representative results. Segregation of grain based on average values of components in hauling vehicles appeared to be feasible. The oil concentration between truck hoppers was significantly different and could be used for binning corn of different concentrations. However, segregation on the combine during harvest does not appear to be feasible due to the large variations that occurred within fields at the same location. For example, the oil concentration of individual ears varied between 1 and 7 percentage points at the same location within the field

Seasonal Aeration Rates for the Eastern United States Based on Long-Term Weather Patterns

Most aeration fans are sized to produce a minimum airflow rate of 0.1 m3/min/t (0.1 cfm/bu) in on-farm grain storage structures. At this airflow rate a significant amount of time is required to move a cooling front completely through a bin. The desired grain temperature and prevailing weather conditions will have a significant effect on required fan size. Thirty years of weather data were analyzed for the eastern United States to determine the amount of time available in temperature windows between 0 to 15.C and 0 to 17.C. Contour maps were generated with ArcMap 8.3 for the percentage of each month within the given temperature windows. A substantial amount of time (over 4% of the month) is available within temperature limits of 0 and 17.C between September and April. This indicates that airflow rates of at least 0.6 m3/min/t (0.5 cfm/bu) would be more adequate to completely move an aeration front through a bin for summer harvested grain in Southern regions of the United States. However, during July and August only the northern half of the United States would have a sufficient amount of time available for cooling grain below 17.C using an airflow rate of 0.1 m3/min/t (0.1 cfm/bu). The maps generated provide a starting point for sizing aeration fans in the eastern United States

Aeration Strategies and Fan Cost Comparisons for Wheat in Mid-South Production Regions

Numerous factors influence the sizing of aeration fans for summer-harvested crops. Thirty years of weather data for Lexington, Kentucky, were analyzed and the cost of aeration was compared for two axial fans (afan1, afan2) and one centrifugal fan (cfan1). Aeration costs were defined as the sum of the following components: the cost of owning the fan, the cost of electricity for operating the fan, a cost for wheat shrinkage during aeration, and a cost for dry matter loss (DML). The fans were selected to deliver airflow rates of approximately one, two, and three times the recommended aeration rate of 0.11 m3/min/t (0.1 cfm/bu). Aeration fan investment costs ranged from $709 (afan1) to$1739 (cfan1). Aeration costs for each fan were compared for four initial grain temperatures: 21.1°C, 23.9°C, 26.7°C, and 29.4°C (70°F, 75°F, 80°F, and 85°F); four harvest dates: 1 June, 15 June, 1 July, and 15 July; and two aeration temperature windows (0 to 15°C and 0 to 17°C). Generally, the total aeration cost increased with initial grain temperature, decreased with later harvest dates, and was not significantly affected by aeration temperature window. When the total cost of aerating the wheat was considered, the results showed that the most expensive fan (cfan1) was not appreciably more costly than the least expensive (afan1). It was also found that using fans with airflow rates above the minimum recommendation were successful in reducing the amount of wheat shrinkage and dry matter loss, which should provide the producer with a larger volume of better quality grain at market