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For the pilotproject ?Effect Monitoring — Biomonitoring of Immission Effects in the Testing Area of Munich”, standardized grass cultures were exposed at 19 locations during 10 series for two weeks each. The grass was analyzed for the accumulation of lead, antimony arsenic, cadmium, and copper. Highest accumulation was observed with antimony near traffic situations. The comparison of the results from the different sampling points identifies motor vehicle traffic as the source of antimony. First examinations of brake linings support this conclusion. Lead is only slightly increased near traffic. Immission-caused copper contents in the grass were found near the overhead tramway cables. The accumulation detection limits for arsenic and cadmium were not exceeded at any of the measuring points.  相似文献   
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Summary The calling song of the -cricket, Teleogryllus commodus, attracts for mating. Both calling and -locomotor activity are under circadian control and the behaviors occur approximately at the same time. Daily playback of calling songs for 3–12 h in constant light failed to entrain -running. Instead, calling acts as an external stimulus which can release -locomotion at any time of the 24-h period, while the clock-induced activity continues to run freely. The stimulatory effect of the calling song causes flexible extension of -locomotor activity, but a subsequent restorative period is necessary. The ecological consequences of acoustical stimulation are discussed.  相似文献   
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Volatile organic compounds were determined in stack-gas emissions from the residential burning of brown-coal briquets using adsorptive enrichment on hydrophobic adsorbents, thermal desorption and capillary-gas chromatographic analysis. 152 compounds were identified and quantified. Quantitative emission factors of the identified individual compounds were determined in relation to the amount of the fuel used. These factors permit assessment of the pollution of the city of Leipzig with volatile organic compounds resulting from the burning of indigenous lignite.  相似文献   
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Biotic and abiotic factors involved in surface coal mine reclamation were evaluated on 81 mine sites in Mercer County, Pennsylvania, USA. Soil moisture and organic content were the two most important factors in determining the establishment and growth of vegetation on mined lands. Soil bacteria and fungi populations were also related to these soil conditions, and soil micro-organisms were important in the decomposition of organic materials as well as factors in the rate and type of natural succession occurring on these lands. The succession of native plant species increases the density and stability of plant communities on mined lands. The importance of natural succession in mined-land reclamation and the use of these lands by wildlife is discussed.Supported by Grant-In-Aid, Natural Geographic Society.  相似文献   
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Tuberous sclerosis (TS) is an autosomal dominant disorder with a high rate of de novo mutation. The real difficulty is to ascertain the diagnosis and to give the neurological prognosis in each case. Prenatal diagnosis of TS is generally based on ultrasonographic signs of multiple cardiac tumours, i.e. rhabdomyomas. Recent progress in magnetic resonance imaging (MRI) enables the diagnosis in a large proportion of cases based on typical brain lesions. It may have a role in the prenatal management of TS, although MRI images seem to underestimate the anatomical findings. Two cases in which TS was diagnosed prenatally are presented with reference to the value of MRI in the prenatal management and comparison with anatomical findings.  相似文献   
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A geothermal survey of the Central Alps, the Swabian volcano, and the Rhinegraben area is presented. New results from seismic surface-wave investigations are used to estimate temperatures at the base of the lithosphere. Cross sections show the high position of the 1000 °C isotherm under the Rhinegraben in relation to its surroundings.  相似文献   
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