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Zum Lebensraumtyp (LRT) zählen natürliche Binnensalzstellen mit ihrem gesamten Lebensraumkomplex sowie anthropogene, naturnah ausgebildete Salzstellen in den Gebieten, in denen primäre Vorkommen zerstört sind. Sekundäre Lebensräume in Naturräumen mit primären Vorkommen sind ausgeschlossen. Der LRT umfasst den gesamten salzbeeinflussten Bereich der Binnensalzstelle.
Der LRT 6130 umfasst natürliche und halbnatürliche lückige bis relativ geschlossene Rasen auf schwermetallreichem Substrat meist älterer Abraumhalden des Bergbaus, auf natürlich oder anthropogen mit Schwermetallen kontaminiertem Flussschotter bzw. auf anstehendem schwermetallhaltigen Gestein (in Sachsen-Anhalt durch Bergbau nahezu vollständig vernichtet). Die Schwermetallrasen sind durch eine hochspezialisierte Flora charakterisiert.
Der LRT umfasst lückige, reichere Sandtrockenrasen mit Vorkommen subkontinental bis kontinental verbreiteter Arten auf Binnendünen und ebenen Sandstandorten, an sandig- anlehmigen Moränenanschnitten sowie auf sandig-grusig verwitternden Gesteinen. Vorkommen auf Sekundärstandorten sind zu berücksichtigen.
Orthotopic bladder cancer xenografts are essential for testing novel therapies and molecular manipulations of cell lines in vivo. Current xenografts rely on tumor cell inoculation by intravesical instillation or direct injection into the bladder wall. Instillation is limited by the lack of cell lines that are tumorigenic when delivered in this manner. The invasive model inflicts morbidity on the mice by the need for laparotomy and mobilization of the bladder. Furthermore this procedure is complex and time-consuming. Three bladder cancer cell lines (UM-UC1, UM-UC3, UM-UC13) were inoculated into 50 athymic nude mice by percutaneous injection under ultrasound guidance. PBS was first injected between the muscle wall and the mucosa to separate these layers, and tumor cells were subsequently injected into this space. Bioluminescence and ultrasound were used to monitor tumor growth. Contrast-enhanced ultrasound was used to study changes in tumor perfusion after systemic gemcitabine/cisplatin treatment. To demonstrate proof of principle that therapeutic agents can be injected into established xenografts under ultrasound guidance, oncolytic virus (VSV) was injected into UM-UC3 tumors. Xenograft tissue was harvested for immunohistochemistry after 23–37 days. Percutaneous injection of tumor cells into the bladder wall was performed efficiently (mean time: 5.7 min) and without complications in all 50 animals. Ultrasound and bioluminescence confirmed presence of tumor in the anterior bladder wall in all animals 3 days later. The average tumor volumes increased steadily over the study period. UM-UC13 tumors showed a marked decrease in volume and perfusion after chemotherapy. Immunohistochemical staining for VSV-G demonstrated virus uptake in all UM-UC3 tumors after intratumoral injection. We have developed a novel method for creating orthotopic bladder cancer xenograft in a minimally invasive fashion. In our hands this has replaced the traditional model requiring laparotomy, because this model is more time efficient, more precise and associated with less morbidity for the mice.
A recent global meta‐analysis reported a decrease in terrestrial but increase in freshwater insect abundance and biomass (van Klink et al., Science 368, p. 417). The authors suggested that water quality has been improving, thereby challenging recent reports documenting drastic global declines in freshwater biodiversity. We raise two major concerns with the meta‐analysis and suggest that these account for the discrepancy with the declines reported elsewhere. First, total abundance and biomass alone are poor indicators of the status of freshwater insect assemblages, and the observed differences may well have been driven by the replacement of sensitive species with tolerant ones. Second, many of the datasets poorly represent global trends and reflect responses to local conditions or nonrandom site selection. We conclude that the results of the meta‐analysis should not be considered indicative of an overall improvement in the condition of freshwater ecosystems.
Vor dem Hintergrund der Hochwässer des Jahres 2002 werden immer wieder Fragen laut, wie die Weichholzauen bezüglich der hydraulischhydrologischen Wirkungen zu beurteilen sind. Die folgenden Aussagen sollen versuchen, einige dieser Fragestellungen unter Bezugnahme auf die mittlere Elbe zu beantworten. Sicherlich ist es nicht möglich, in diesem Zusammenhang jeden Einzelaspekt ausreichend zu beleuchten, zumal sich auch die Autoren der ausgewerteten Quellen hinsichtlich eindeutiger Aussagen relativ „bedeckt“ halten. Es können lediglich allgemeine Ausführungen bezüglich möglicher Wirkungen gemacht werden. Eine Klärung von realen Auswirkungen der Weichholzauen ist nur am objektkonkreten Beispiel möglich, da nur dort alle Rahmenbedingungen ausreichend berücksichtigt werden können.
Die natürlichen Überflutungsräume morphodynamisch intakter, frei fließender Oberflächengewässer, insbesondere großer Flussauen mit ihren Lebensraumtypen und flussauentypischen Lebensgemeinschaften, gehören zu den besonders gefährdeten Lebensräumen in Deutschland. Gleichzeitig sind Auenlandschaften die vom Menschen bevorzugten Siedlungsgebiete. Damit verbunden ist eine seit Jahrhunderten andauernde anthropogene Veränderung der Auen. Deshalb ist auch an der Mittleren Elbe von einem erheblichen Verlust des auentypischen Gewässerbestandes auszugehen. Teilweise verliefen diese Veränderungen schleichend und von der Öffentlichkeit kaum bemerkt. Bekannt ist, dass diese Eingriffe als sekundäre Folgeschäden langfristig und zeitversetzt wirken. Im Folgenden sollen die Ursachen für den erheblichen Verlust von Gewässerflächen und Veränderungen der Auenstrukturen analysiert und grundlegende Möglichkeiten der Renaturierung wertvoller Gewässerstrukturen durch Einbindung des vorhandenen Restbestandes natürlicher Altwasser und anthropogen entstandener Auengewässer aufgezeigt werden
Background: The neurophysiological and neuroanatomical foundations of persistent developmental stuttering (PDS) are still a matter of dispute. A main argument is that stutterers show atypical anatomical asymmetries of speech-relevant brain areas, which possibly affect speech fluency. The major aim of this study was to determine whether adults with PDS have anomalous anatomy in cortical speech-language areas. Methods: Adults with PDS (n = 10) and controls (n = 10) matched for age, sex, hand preference, and education were studied using high-resolution MRI scans. Using a new variant of the voxel-based morphometry technique (augmented VBM) the brains of stutterers and non-stutterers were compared with respect to white matter (WM) and grey matter (GM) differences. Results: We found increased WM volumes in a right-hemispheric network comprising the superior temporal gyrus (including the planum temporale), the inferior frontal gyrus (including the pars triangularis), the precentral gyrus in the vicinity of the face and mouth representation, and the anterior middle frontal gyrus. In addition, we detected a leftward WM asymmetry in the auditory cortex in non-stutterers, while stutterers showed symmetric WM volumes. Conclusions: These results provide strong evidence that adults with PDS have anomalous anatomy not only in perisylvian speech and language areas but also in prefrontal and sensorimotor areas. Whether this atypical asymmetry of WM is the cause or the consequence of stuttering is still an unanswered question. This article is available from: http://www.biomedcentral.com/1471-2377/4/23 © 2004 Jäncke et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Under certain conditions, secondary organic aerosol (SOA) particles can exist in the atmosphere in an amorphous solid or semi-solid state. To determine their relevance to processes such as ice nucleation or chemistry occurring within particles requires knowledge of the temperature and relative humidity (RH) range for SOA to exist in these states. In the Cosmics Leaving Outdoor Droplets (CLOUD) experiment at The European Organisation for Nuclear Research (CERN), we deployed a new in situ optical method to detect the viscous state of α-pinene SOA particles and measured their transition from the amorphous highly viscous state to states of lower viscosity. The method is based on the depolarising properties of laboratory-produced non-spherical SOA particles and their transformation to non-depolarising spherical particles at relative humidities near the deliquescence point. We found that particles formed and grown in the chamber developed an asymmetric shape through coagulation. A transition to a spherical shape was observed as the RH was increased to between 35 % at −10 °C and 80 % at −38 °C, confirming previous calculations of the viscosity-transition conditions. Consequently, α-pinene SOA particles exist in a viscous state over a wide range of ambient conditions, including the cirrus region of the free troposphere. This has implications for the physical, chemical, and ice-nucleation properties of SOA and SOA-coated particles in the atmosphere.