Verhalten und Neurobiologie von stimmbegabten Insekten

Crickets, tettigoniids (bush crickets or long-horned grasshoppers) and acridids (short-horned grasshoppers) are well-suited animals to study acoustically mediated behavior and to search for the underlying sensory, nervous, and effector mechanisms. Several behavioral tactics are described which improve reproductive success, serve to avoid predators such as bats, or have been developed for defence against parasitic insects. Phonotactic orientation of female crickets toward the calling male was chosen, since for this behavior the underlying sensory and nervous mechanisms have been intensively studied. Song recognition was found to be based on one critical parameter of the song, thesyllable period, and the females show abandpass behavior for which a correlate exists inlocal brain neurons. Sound orientation is based on apressure gradient mechanism in each ear, and it needs abinaural intensity comparison within the central nervous system. With intracellular recordings from auditory interneurons during phonotactic orientation and their manipulation, a cellular correlate could be found which obeys the rule “turn to the side most strongly stimulated”.     

Time study on the uptake of four different beta-blockers in garden cress (Lepidium sativum) as a model plant

Environmental Science and Pollution Research - The aim of this study was to investigate the uptake of four beta-blockers by the model plant Lepidium sativum (garden cress) and their possible...     

The effect of ozone on pollen development in Lolium perenne L

Perennial ryegrass plants (Lolium perenne L.) were exposed in "Closed-Top Chambers" to different ozone concentrations and to charcoal filtered ambient air to study the effect of ozone on the development of pollen. Ozone at ambient (65 nl l(-1), 8h) and elevated (110 nl l(-1), 4h) concentrations affected the maturing of pollen by inhibiting starch accumulation in pollen throughout the anther. Affected pollen persisted in the vacuolated state while normal pollen in the same anther were filled with amyloplasts. The percentage of underdeveloped pollen-determined in transversal sections-was significantly higher in exposed plants than in plants grown in filtered air. Results indicate that ozone stress was responsible for the disrupted development of pollen in L. perenne.     

MR imaging of the fetal musculoskeletal system

Magnetic resonance imaging (MRI) appears to be increasingly used, in addition to standard ultrasonography for the diagnosis of abnormalities in utero. Previous studies have recently drawn attention to the technical refinement of MRI to visualize the fetal bones and muscles. Beyond commonly used T2-weighted MRI, echoplanar, thick-slab T2-weighted and dynamic sequences, and three-dimensional MRI techniques, are about to provide new imaging insights into the normal and the pathological musculoskeletal system of the fetus. This review emphasizes the potential significance of MRI in the visualization of the fetal musculoskeletal system. © 2012 John Wiley & Sons, Ltd.     

Passivsammler zur Wasseruntersuchung

The topography and motion of contaminant plumes in groundwater may be determined by surveying the three-dimensional distribution of contaminant freights [1] as well as through a period-integral monitoring by contaminant dosimeters [1]. Conventional methods of taking water samples for chemical analysis cannot fulfill any of these requirements. Sorption active passive collectors suitable for corresponding surveys in gaseous phases are unsuitable for examination in aquifers. Passive collectors for the examination of undisturbed aquifers represent the central part of a probing device system developed by the authors for monitoring chemical and hydraulic parameters within all kinds of aquifers. These passive collectors permit both a determination of the relative contaminant freights at deliberate vertical spacing of vertically ordered measuring points, and period-integrating detection of vertical profiles of relative contaminant freights. The easy-to-handle passive collectors are suitable for the collection of organic and inorganic contaminants and may be evaluated by standardized chemical analysis methods. In this way, passive collectors fulfill the essential prerequisites for purpose-oriented monitoring of contaminant plumes. Moreover, passive collectors for ground water monitoring are well suited for the in situ-examination of any other aquifer, both still and fluent, regardless of its depth or extent. Examples of application may be sewage ducts, sewage plants, rivers, lakes, oceans, water samples and especially the identification of contaminants and trace substances.