Acidity neutralization mechanism in a forested watershed in Central Japan

The contributions of cation exchange and mineral weathering to the neutralization of acidity in the Jingahata watershed in central Japan were estimated through a laboratory weathering experiment and runoff chemistry measurements. The laboratory experiment was conducted in a stirred-flow reactor for a whole soil sample collected from the C horizon in the watershed. The concentration ratios of base cations (Ca²⁺, Mg²⁺, K⁺ and Na⁺) to Si (BC/Si) released during the steady-state stage of the laboratory experiment were in good agreement with the ratios of the net flux of base cations to the flux of Si in the streamwater (BC _{N ET}/Si _L).This result suggests that the acidity in the watershed is neutralized primarily by mineral weathering without causing a net loss of base cations from exchange sites. The alkalinity/acidity balance estimated for the watershed shows that the total weathering rate of base cations is approximately 3.26 keq ha^?1 yr^?1. Weathering of plagioclase (An₄₁) contributes 83% of the total weathering rate. The dominant acidity source is CO₂ released within the soil horizons, accounting for roughly 85% of the total acidity flux (3.20 keq ha^?1 yr^?1). This high internal production of acidity suppresses the relative importance of atmospheric acidity inputs (0.3 keq ha^?1 yr^?1).     

Oxygen Isotopic and Chemical Characterization of Soils with Surface Gleyzation from Central and Northeastern Japan

Four soils with surface gleyzation (Humi-stagnic Gleysols; provisional) from central and northeastern Japan are characterized by a combination of oxygen isotopic, chemical dissolution (pyrophosphate and acid oxalate) and X-ray diffraction analyses. Oxygen isotopic composition of quartz indicates residuum of volcanic materials and eolian dust from interior China as major parent materials of the clayey surficial horizons.     

Microparticle dispensers for the controlled release of insect pheromones

The potential utility of micrometer-sized particles as controlled-release devices for the volatilization of insect pheromones for mating disruption applications is evaluated in this study for two pheromone/model compound systems (codlemone/1-dodecanol and disparlure/1,2-epoxyoctadecane). To expedite the measurement of release rates from these particle devices, two techniques based on thermogravimetric analysis (TGA) have been exploited: isothermal TGA (I-TGA) at elevated temperatures (40-80 degrees C) with N(2) convection and volatilization temperature (VT) by dynamic TGA. A correlation between these two methods has been established. Samples that exhibit a higher VT provide a lower release rate from a particle substrate. Using these techniques, it has been demonstrated that chemical interactions between adsorbed liquids and particle surfaces may play a small role in defining release characteristics under conditions of low surface area, whereas parameters associated with total surface area and micropore structure appear to be much more significant in retarding evaporation for uncoated particles containing an adsorbed liquid. Additional regulation of release rates was achieved by coating the particle systems with water-soluble or water-dispersible polymers. By careful selection of particle porosity and coating composition, it is envisioned that the evaporation rate of pheromones can be tailored to specific insect control applications.     

Effects of citric acid on the viscoelasticity of cornstarch pastes

The effects of citric acid on the rheological properties of cornstarch pastes were studied by steady shear and dynamic oscillatory viscoelasticity, intrinsic viscosity measurements and microscopic observation. The pH of cornstarch dispersion was adjusted between 6.0 and 3.0. The viscosity of the pastes was increased by lowering the pH (between 5.5 and 3.6), while the viscosity of samples with pH below 3.5 decreased further than that of the control (pH = 6.3). Citric acid promoted the collapse of starch granules; however, adding excessive citric acid led to the hydrolysis of glucose chains. No decrease in the viscoelasticity was observed for cornstarch pastes by adding acid at 25 degrees C after gelatinization.     

PMSG profiles in superovulated and anti-PMSG antiserum treated mice and heifers with enzymeimmunoassay

A sandwich enzymeimmunoassay (EIA) for pregnant mare serum gonadotropin (PMSG) using a microtiter plate was developed. Sensitivity of the assay to PMSG was 15.6 mIU/ml (0.2 ng/well). The PMSG levels in serum were measured with the EIA in superovulated and anti-PMSG rabbit antiserum treated mice and heifers. In mice, the PMSG blood level was measurable in the serum 4-6 days after intraperitoneal injection of 5-30 IU of PMSG. The administration of anti-PMSG antiserum at the same dose level as PMSG caused a rapid decrease in the PMSG blood level, declining to undetectable levels within 17 hours. In heifers, the PMSG level was measurable at 10-11 days after the injection of 2500 or 3000 IU of PMSG. When antiserum was injected 48 hours after the PMSG injection, the clearance rate of PMSG was affected by the route of the administration. The administration of 3000 units of anti-PMSG antiserum intravenously caused a rapid decline and the disappearance of circulating PMSG within 17 hours. When 3000 units of anti-PMSG antiserum was injected intra-muscularly, the PMSG blood level also decreased and became unmeasurable 24 hours after administration; however, it was still detectable for up to 17 hours. These results indicate that the administration of anti-PMSG antiserum at the proper timing and dosage could lead to successful superovulation through the improvement of hormonal conditions.     

Sulfadimethoxine residue in broiler-chicken skin.

The disposition and elimination of sulfadimethoxine (SDMX) in the skin of broiler-chickens were investigated. The administration of SDMX, in drinking water, at a concentration of 1,000 ppm for 5 days demonstrated that the SDMX was eliminated much more slowly from the skin than from the other tissues or plasma. These results were duplicated and confirmed in another experiment, in which a single dose of 200 mg/kg BW of SDMX was administered via a stomach tube. No significant difference in the SDMX residue level was observed between the broiler-chickens that had their skin surface sealed versus the non-sealed animals and that had ingested SDMX in their drinking water. This illustrated the higher SDMX residue in the skin was not attributable to external SDMX contamination from the drinking water, feces or urine. In addition, there was no significant difference among the SDMX residue concentrations in the thoracic, dorsal and leg skin samples, following an intravenous injection of SDMX (30 mg/kg BW). This indicated that the SDMX was distributed evenly throughout the entire skin area of the broiler-chickens.     

Effect of incubation temperature or maternal antibody on virus growth and mortality of embryonated chicken eggs inoculated with the B1 strain of lentogenic Newcastle disease virus

The effects of incubation temperature on virus growth and mortality patterns were studied in antibody-free chicken eggs inoculated with the B1 strain of Newcastle disease virus. Embryo mortality patterns did not differ much between 37, 39, and 41 C of incubation, although virus growth curves were higher at 39 C and 41 C than at 37 C. Below 35 C, embryo mortality was delayed, although from 48 hours after incubation the virus growth curves were similar to those at 37 C. In eggs with and without maternal antibody, virus titers were maximum 48 hours after incubation, although slightly higher in antibody-free eggs than in eggs with antibody whether the eggs were alive or dead. Eggs with maternal antibody had delayed mortality patterns.     

Purification of a protein from serum of cattle with hepatic lipidosis, and identification of the protein as haptoglobin.

A protein that has 2 subunits with molecular weight of 35,000 and 23,000 was detected in serum of cattle with hepatic lipidosis (fatty liver). The protein was purified from serum obtained from a cow with fatty liver, and was identified as haptoglobin, which is known to have hemoglobin-binding capacity and to be an acute-phase protein. To assess the relevance of haptoglobin in fatty liver, cattle were classified in 3 groups (healthy control, haptoglobin-positive, and haptoglobin-negative); liver triglyceride content and several serum biochemical variables were evaluated for the 3 groups. Compared with the control and haptoglobin-negative cattle, haptoglobin-positive cattle had significantly (P less than 0.01) higher liver triglyceride content, serum bilirubin concentration, and aspartate transaminase activity. Serum haptoglobin concentration was high in slaughter cattle (27 of 40 cattle tested), particularly in cows (20/28).