Elution of glomerular bound antibodies in experimental streptococcal glomerulonephritis

lmmnunoglobulin G, eluted from glomeruli of rats with streptococcal glomerulonephritis, reacts with type 12 M protein of the streptococcus but not with other streptococcal or renal antigens. Thtrefore, this disease may be madiated by fixation of antigen-antibody complexes consisting of streptococcal M protein and type-specific antibody.     

Blood selenium in a beef hern affected with muscular degeneration

In a Hereford herd in the middle of Sweden high mortality occurred in the calves in 1967 and 1968. Most frequent symtoms were respiratory distress and weakness. The diagnosis M.D. was established by postmortem examination. For this reason a study was made of the selenium content in forage, in blood and milk from cows and in blood from their offspring. The Se analyses were made by the method of Lindberg (1968).     

Lack of virus transmission from bovine viral diarrhoea virus infected calves to susceptible peers

None of 14 calves not previously exposed to BVDV became infected after being forced to have nose-to-nose contact with a group of 5 calves primarily infected with BVDV. These were 5 male calves primarily infected with a type I BVDV strain, after nose-to-nose contact with a persistently viraemic calf. All 5 became infected and were clinically affected. They were slightly depressed and pyretic at 8-9 days post-infection, with a body temperature of up to 41.6 degrees C, but no medical treatment was required. Seroconversions to BVDV were detected in these calves at 14 to 21 days post-infection. The 14 healthy calves, proved to be free from BVD virus--as well as antibodies, were introduced 2 by 2 into the group of 5 primarily infected calves on days 4, 7, 14, 21, 28, 35 and 42 after the 5 calves had been in contact with the persistently BVDV-infected calf. Each pair of calves stayed within the primarily infected group for 2 days. None of these 14 calves seroconverted to BVDV.     

Radio and plasma wave observations at Saturn from Cassini's approach and first orbit

We report data from the Cassini radio and plasma wave instrument during the approach and first orbit at Saturn. During the approach, radio emissions from Saturn showed that the radio rotation period is now 10 hours 45 minutes 45 +/- 36 seconds, about 6 minutes longer than measured by Voyager in 1980 to 1981. In addition, many intense impulsive radio signals were detected from Saturn lightning during the approach and first orbit. Some of these have been linked to storm systems observed by the Cassini imaging instrument. Within the magnetosphere, whistler-mode auroral hiss emissions were observed near the rings, suggesting that a strong electrodynamic interaction is occurring in or near the rings.     

Relationship between selenium content of forage, blood and organs of sheep, and lamb mortality rate

The investigation comprised 12 herds, totalling 660 sheep, in the counties of Stockholm and Uppsala. The selenium content of specimens of forage, whole blood, muscle, liver, and kidney was determined by a fluorimetric method. Data on the number of born and dead lambs were collected 4—5 months after lambing. Dead and sick lambs were subjected to necropsy and to clinico-chemical analyses, respectively.The selenium content of hay and corn was lower than 60 ng per g, which some authors regard as the minimum level of Se requirement for protection against white muscle disease in sheep. The analyses of forage mixtures containing oil concentrates and beet pulp showed selenium levels that were about 2—5 times as high as this minimum level.In herds in which the animals had not been treated with selenium preparations prior to sampling, there was a significant positive correlation between the selenium content of the forage and that of whole blood. A relationship was also noted between the selenium content of forage and of organs.In 9 out of the 12 herds the selenium concentrations in whole blood were on the level that is considered to be representative of white muscle disease.A high mortality rate was recorded for lambs whose mothers had low selenium levels in their blood.Prophylactic and curative treatment with selenium plus vitamin E orally and/or parenterally probably reduced lamb mortality rate in the herds fed a low-selenium diet.     

Measurement of cell wall penetration in wood of water-based chemicals using SEM/EDS and STEM/EDS technique

Summary The penetration of bulking chemicals (glycerol, PEG 200, PEG 1500 and pentaerythritol) into the cell wall of wood, Pinus sylvestris, has been studied. A number of different methods for determining the distribution of chemicals in the cell wall were used. Measurements of the increase in cell wall thickness showed that glycerol and PEG 200 resulted in greater cell wall bulking compared to PEG 1500 and pentaerythritol. Examination with SEM/EDS-linescan confirmed these results. However, the better resolution possible with the STEM/EDS-linescan revealed an inhomogenous distribution of the chemical in the cell wall. This is believed to be due to microcracks in the cell wall which are the result of the initial drying of the wood. This general damage to the cell wall could be the reason for the failure to find a stabilizing chemical and method. Received 10 February 1997     

Wood surface stabilization with polyethyleneglycol,PEG

Summary The possibilities of interaction between wood, Pinus sylvestris, (60% RH) and potassium stained PEG 1500 (polyethyleneglycol) have been investigated using Scanning Electron Microscopy (EDS-analysis), dynamical mechanical techniques (DMTA) and X-ray diffraction (WAX).The EDS-analysis shows an even distribution of potassium in the cell wall. On the other hand the predicted cell wall swelling associated with PEG absorption is absent. This indicates that the method of staining PEG with potassium does not work. The DMTA-measurements show interaction on the molecular level between wood and PEG 1500. EDS-analysis, SEM- and WAX-investigations show free PEG in the impregnated specimens.     

Atmospheric concentrations and deposition of Hg to A deciduous forest atwalker branch watershed,Tennessee, USA

Aerosol and total vapor-phase Hg concentrations in air have been measured at Walker Branch Watershed, Tennessee for ≈ 2 yr. Airborne Hg at this site is dominated by vapor forms which exhibit a strong seasonal cycle, with summer maxima that correspond to elevated air temperature. Concentrations in this forest are near background levels; however, concentrations at a site within 3 km are significantly elevated due to emissions from Hg-contaminated soils. The concentration data have been combined with a recently modified dry deposition model to estimate dry deposition fluxes to the deciduous forest at Walker Branch. Weekly mean modeled V_d values for Hg° ranged from <0.01 (winter) to > 0.1 (summer) cm s¹. Weekly dry deposition fluxes ranged from <0.1 μg m⁻² during winter to > 1.0 μgg m⁻² in the summer. Our dry deposition estimates plus limited measurements of wet deposition in this area indicate that dry deposition may be the dominant input process in this forest, at least during the summer.