Prüfung der Auswirkungen von Pflanzenschutzmitteln auf Nutzarthropoden und deren Einbeziehung in die Zulassung

Tests of side-effects of pesticide on beneficial arthropods and their incorporation into registrationSimulated by the expences of integrated plant protection and based on the plant protection law of the Federal Republic of Germany, a German working group (directed by the Biologische Bundesansalt) since 1970 and an International (WPRS) Working Group since 1974 intiated a systematic study of side-effects of pesticides on beneficial (entomophagous) arthropods. The present status of this work is being reported which intends to obtain guide-lines for tests following standardized principles, which will allow, at first ona voluntary basis, acceptance os a test complementary to the protocol for registration as presently applied. This was officially started in the Fed, Rep. of Germany on October 1, 1975, covering, at first, 3 common and important species of entomophagous parasites (in the laboratory) and one field test developed for the surveys of the fauna of apple trees. Some details of the test, the evaluation of results, and the contributions of experts from member countries of WPRS/IOBC are reported upon. This complementary test, geared from the beginning at an international cooperation, will lesd in all co-operating countries to an enlarged basis for a correct assessment of the total impact of pesticides as it is needed for an effective applicaton of integrated plant protection.     

Übersicht und Bestimmungstabelle der europäischen nadelholzbewohnenden Siriciden (Hymenoptera,Symphyta)

Ohne Zusammenfassung     

Serum sialic acid levels increased in tumor-bearing dogs

Serum concentrations of lipid-soluble (glycolipid) sialic acid were determined for 96 client-owned dogs, of which 24 were diagnosed as bearing tumors. A markedly increased concentration of lipid-soluble serum sialic acid was found in 22 of 24 tumor-bearing dogs (92%) compared with 17 of 72 dogs with other definitely false-positive, based on necropsy and follow-up work. Almost all others had acute infections or terminal congestive disorders and were potential tumor bearers. The values obtained appeared to be independent of the sex or age (or both) of the dogs. Based on the analysis of a single biochemical variable, the procedure may permit cancer detection applicable to a wide range of tumor types in dogs if evaluated in terms of the general health status of the animal.     

Ultrasonography of the teat canal in cows and sheep

When the isolated teat of a cow was examined with an 8.5 MHz linear array transducer in a vertical plane, the teat canal appeared as a thin, white line, bordered on each side by parallel, thick, grey-black bands. In a horizontal plane a comparable image was obtained. In a sheep, images of comparable quality were obtained with a 12 MHz transducer. Histological studies of the tissues whose removal led to the disappearance of this characteristic ultrasonographic appearance showed that it was associated with the stratified keratinised squamous epithelium with distinct papillae. The content of keratin in the stratum corneum was apparently responsible for the bright zone; the stratum lucidum was not visible, and the surrounding dark, less echoic area was associated with the stratum granulosum. Doppler echography in live animals confirmed this designation. The outer layers of the teat wall were more echogenic.     

The force needed to move an atom on a surface

Manipulation of individual atoms and molecules by scanning probe microscopy offers the ability of controlled assembly at the single-atom scale. However, the driving forces behind atomic manipulation have not yet been measured. We used an atomic force microscope to measure the vertical and lateral forces exerted on individual adsorbed atoms or molecules by the probe tip. We found that the force that it takes to move an atom depends strongly on the adsorbate and the surface. Our results indicate that for moving metal atoms on metal surfaces, the lateral force component plays the dominant role. Furthermore, measuring spatial maps of the forces during manipulation yielded the full potential energy landscape of the tip-sample interaction.