Thymosin-testosterone interaction in spontaneous rosette formation in the baboon monkey (Papio papio)

Thymosine fraction V was shown to exert a stimulation activity on T lymphocytes from Papio papio, as determined by E. Rosette and active E. Rosette formation. Testosterone inhibited this effect of thymosin.     

Clinical field study to evaluate the efficacy and safety of the amino-acetonitrile derivative, monepantel, compared with registered anthelmintics against gastrointestinal nematodes of sheep in Australia

Objective   To determine the efficacy of monepantel, a developmental compound from the amino-acetonitrile derivative class of anthelmintics, against field infections of gastrointestinal nematodes in sheep.
Procedures   Comparisons of efficacy (using standard faecal worm egg count reduction tests) and safety (on the basis of visual observations) were made in a large-scale field study in Australia, between groups of sheep treated with either an oral solution of monepantel or a registered anthelmintic. The sheep were naturally infected with the major gastrointestinal nematode genera present in Australia.
Results   The post-treatment efficacy results for monepantel were: at 7 days (±1 day) efficacy was >98%; at 14 days (±1 day) it was generally close to or >99%; and at 21 days (±1 day) efficacy was consistently >99%. A high proportion of the targeted nematode populations were confirmed as being resistant to one or more of the currently available anthelmintic classes.
Conclusions   Monepantel when used under field conditions at a minimum dose rate of 2.5 mg/kg was highly effective against mixed-genus natural field infections of the major gastrointestinal nematode genera including Haemonchus , Teladorsagia ( Ostertagia ), Trichostrongylus , Nematodirus , Chabertia and Oesophagostomum . This result included efficacy against some populations resistant to the currently available broad-spectrum anthelmintics. Few Cooperia spp. were present to allow confirmation of efficacy against this genus. On no occasion after treatment did any commercial anthelmintic-treated groups have significantly lower faecal egg counts than the monepantel-treated groups. Monepantel was safe for the target animals and human operators when used in a field situation.     

Investigations concerning the sustainability of remediation by land deposition of tributyltin contaminated harbour sediments

Sediments often contain high concentrations of tributyltin, which is used as a biocide in antifouling paints. The aim of our project was to assess land deposition as an alternative in dealing with TBT-contaminated harbour sediments. Therefore, we followed the biological degradation of TBT under aerobic and anaerobic conditions at different temperatures using defined laboratory experiments and performing field measurements. With the data obtained, a risk assessment is performed. The biological degradation of TBT is faster under aerobic conditions and with increasing temperature. The half-lives found show the dependency of the degradation rates on the temperature between 5 to 55°C The degradation rate determined for water under the same conditions (just biological degradation, without photolysis) is almost 4 times higher than in the sediment. The field studies gave a degradation rate of around 10% per year in untreated sediment and 30% per year in restacked sediments. We did not observe any interference of released TBT with ground water or surrounding areas. The TBT uptake in plants was low. Based on our results, a multidimensional risk evaluation was done, concerning the TBT and its degradation products dibutyl tin (DBT) and rnonobutyl tin (MBT) released from the deposition area. The land deposition appears to be a sustainable solution for dealing with TBT-contaminated harbour sediments. Compared to other disposals, it is economically one of the cheapest and, from an ecological point of view, it is acceptable.     

Structure of binary solution droplets: Continuum theory and Monte Carlo simulation

To calculate the formation energy of a binary mixture droplet out of the gas phase in classical ‘heteromolecular’ nucleation theory, one has to take into account that the concentration of the solution near the droplet surface can be different from the composition in the droplet interior (‘surface enrichment’, Gibbs adsorption equation). This problem is solved in a simple picture where the composition varies spatially but where one has a sharp liquid-gas surface. In a material independent continuum theory, the variation of the composition is assumed to give a free energy contribution proportional to the square of the concentration gradient. This treatment of the surface enrichment gives a formation energy contribution smaller (for large droplets) by a factor 1 ^?1/√3 than previous theories (Döring and Neumann, 1940; Stauffer and Kiang, 1974), which therefore overestimated the surface enrichment for large droplets. This continuum theory is tested by Monte Carlo methods on a particularly symmetric mixture, the magnetic spin 1/2 Ising model. Here up-spins are identified with one type of molecule and down spins with another type. Reasonable agreement with the continuum theory is found, even for parameter ranges where the assumptions of the continuum theory are no longer valid. The results show clearly a strong but smooth variation of the concentration within the droplet. They constitute to our knowledge the first computer simulations of mixture microclusters.     

Environmental Impacts of Landfill Bioreactorcells in Comparison to Former Landfill Techniques

Former and present landfill techniques at the Filbornaplant in Helsingborg, South Sweden are compared withrespect to impacts on the environment. This includes thepotential for nutrient recovery and heavy metalimmobilisation in the waste residue. The results showthat optimised landfill bioreactor-cells have a higherturn-over rate for organic matter compared to the formerlandfills, whereas the retention capacity for heavymetals in both systems was surprisingly high. Full scaleleachate data, as well as a laboratory leachingexperiments confirmed the role of bioreactor cells asanaerobic filters enabling a separation of nutrients froma mixed waste, while the toxic metals are retained. Theconclusion of this article is that by simple measures, thebiological processes can be optimised, resulting inhigher turn-over rates for organic matter and thusaccelerated waste stabilisation.