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91.
Multiple sulphatase deficiency was diagnosed in the first trimester of pregnancy by demonstrating markedly reduced activities of arylsulphatases and heparin sulphamidase by direct assays on chorionic villi (CV). The diagnosis was confirmed by assays on cell cultures of villi and fetal skin fibroblasts. Two further pregnancies of this mother were monitored similarly and predicted to be unaffected; one produced a normal healthy infant, the other miscarried shortly after CV sampling. 相似文献
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93.
Plasticity in echolocation signals of European pipistrelle bats in search flight: implications for habitat use and prey detection 总被引:1,自引:1,他引:0
We studied the echolocation and hunting behavior of three aerial insectivorous species of bats (Vespertilionidae: Pipistrellus) in the field in order to characterize the signals used by the bats and to determine how call structure varies in relation to habitat structure (uncluttered versus cluttered space). We documented free-flying, naturally foraging wild pipistrelles in various habitats using multiflash stereophotography combined with simultaneous sound recordings. Then we reconstructed the bat's flight position in three-dimensional space and correlated it with the corresponding echolocation sequences. In all three species of pipistrelles, signal structure varied substantially. In echolocation sequences of the search phase we found a consistent association of signal types with habitat types. In uncluttered habitats (obstacles more than 5 m from the bat) pipistrelles emitted almost exclusively narrowband signals with bandwidths less than 15 kHz. In cluttered habitats (obstacles less than 5 m from the bat) they switched to signals with bandwidths of more than 15 kHz. Wideband signals were also used when the bats were turning in cluttered and uncluttered spaces and for an instant after turning away from obstacles. Prey detection occured only when the outgoing signal did not overlap with the returning echo from potential prey. The bats also avoided overlap of echoes from potential prey and obstacles. Based on the results of this study, we propose an overlap-free window within which pipistrelles may detect potential prey and which allows predictions of minimum distances to prey and clutter-producing objects.
Correspondence to: E.K.V. Kalko 相似文献
94.
The glial fibrillary acidic protein (GFAP) is the subunit protein of intermediate filaments in astrocytes and closely related cell types. By means of an enzyme immunoassay we have determined the concentration of GFAP in amniotic fluids from normal pregnancies and from pregnancies complicated by various fetal malformations. The group of 20 cases of fetal anencephaly had a significantly higher mean amniotic fluid GFAP concentration (115 μg/1±133.6 (S.D.), range 6–378 μg/1) than the control group of 117 normal pregnancies (13 μg/1k±5.5 (S.D.), range 0–31 μg/1), (P<0.001). Two cases of fetal encephalocele likewise had very high amniotic fluid GFAP concentrations. None of the other cases of fetal malformations investigated, including 12 cases of spina bifida, had increased amniotic fluid GFAP concentrations. We conclude that determination of the amniotic fluid GFAP concentration may give additional information in the prenatal diagnosis of fetal nervous system malformations. 相似文献
95.
Many sites of former ammunition plants are contaminated with the explosive 2,4,6-trinitrotoluene, its derivatives and reduction products. Such nitroaromatic compounds have a high human and ecotoxic potential. Plant uptake of these organic pollutants is known and could be confirmed under field conditions. In this paper rhizospheric soil was analyzed to characterize the effect of vegetation on TNT-contaminated soil. Common beans (Phaseolus vulgaris) were used as test plants. The experiments were performed on two areas with different TNT concentrations. The data reveal a significant decrease of extractable TNT in rhizospheric soil by a factor of 5 to 6 during the vegetation period. On the area with high TNT concentration, an enrichment of nitroaromatic compounds in root tissue was found compared to the rhizospheric soil. Aminodinitrotoluene could be confirmed as the primary pollutant in the root. These results refer to a potential application of plants to biological remediation of soil contaminated with ammunition-specific pollutants. 相似文献
96.
Bastian Herzog Hilde Lemmer Bettina Huber Harald Horn Elisabeth Müller 《Environmental science and pollution research international》2014,21(4):2795-2804
The intensive use of benzotriazoles as corrosion inhibitors for various applications and their application in dishwasher detergents result in an almost omnipresence of benzotriazole (BTri), 4-methyl- and 5-methyl-benzotriazole (4-TTri and 5-TTri, respectively) in aquatic systems. This study aims on the evaluation of the biodegradation potential of activated sludge communities (ASCs) toward the three benzotriazoles regarding aerobic, anoxic, and anaerobic conditions and different nutrients. ASCs were taken from three wastewater treatment plants with different technologies, namely, a membrane bioreactor (MBR-MH), a conventional activated sludge plant CAS-E (intermittent nitrification/denitrification), and CAS-M (two-stage activated sludge treatment) and used for inoculation of biodegradation setups. All ASCs eliminated up to 30 mg L?1 5-TTri and BTri under aerobic conditions within 2–7 and 21–49 days, respectively, but not under anoxic or anaerobic conditions. 4-TTri was refractory at all conditions tested. Significant differences were observed for BTri biodegradation with non-acclimated ASCs from MBR-MH with 21 days, CAS-E with 41 days, and CAS-M with 49 days. Acclimated ASCs removed BTri within 7 days. Furthermore, different carbon and nitrogen concentrations revealed that nitrogen was implicitly required for biodegradation while carbon showed no such effect. The fastest biodegradation occurred for 5-TTri with no need for acclimatization, followed by BTri. BTri showed sludge-specific biodegradation patterns, but, after sludge acclimation, was removed with the same pattern, regardless of the sludge used. Under anaerobic conditions in the presence of different electron acceptors, none of the three compounds showed biological removal. Thus, presumably, aerobic biodegradation is the major removal mechanism in aquatic systems. 相似文献
97.
98.
99.
Elisabeth Heidenreich 《Environment, Development and Sustainability》2009,11(6):1145-1154
Modern societies organize and consume their basic natural resources in great technical infrastructures of transport, supply,
communication, and information. Together with these infrastructures a new culture emerged, which influences since the 19th
century the perception of nature. This article reflects on technical infrastructures as spaces of flow, which mediate technically and culturally between society and nature and on the necessity to evolve a new cultural perception
of them. The vital importance of technical spaces of flow for daily life will be shown in the first part. The second part
reveals the history and some characteristics and environmental impacts of technical spaces of flow. Their threefold spatial
structure and typical conflicts arising at each spatial segment will be described in the third part. The last part investigates
the cultural perception of technical spaces of flow, the natural resources they mediate and the environmental impacts they
cause. They are the technical spaces and flowing processes themselves, which lead to a false cultural perception of the modern
interaction with nature and to the necessity of political, technical, esthetical, and planning measures in order to make spaces
of flow and flowing processes “visible” and to evolve a new, sustainable consumption culture. 相似文献
100.
Sofia Ahlroth Måns Nilsson Göran Finnveden Olof Hjelm Elisabeth Hochschorner 《Journal of Cleaner Production》2011,19(2-3):145-156
In environmental systems analysis tools like Life Cycle Assessment, strategic environmental assessment, cost–benefit analysis and environmental management systems, results need to be presented in a comprehensible way to make alternatives easily comparable. One way of doing this is to aggregate results to a manageable set by using weighting methods. In this paper, we explore how weighting methods are used in some selected Environmental Systems Analysis Tools (ESATs), and suggest possible developments of their use. We examine the differences in current use patterns, discuss the reasons for and implications of such differences, and investigate whether observed differences in use are necessary. The result of our survey shows that weighting and valuation is broadly used in the examined ESATs. The use of weighting/valuation methods is different in different tools, but these differences are not always related to the application; rather, they are related to traditions and views on valuation and weighting. Also, although the requirements on the weights/values may differ between tools, there are intersections where they coincide. Monetary weights, using either endpoint or midpoint methods, are found to be useful in all the selected tools. Furthermore, the inventory shows that that there is a common need for generic sets of weights. There is a need for further research focusing on the development of consistent value sets derived with a wide range of methods. In parallel to the development of weighting methods it is important with critical evaluations of the weighting sets with regard to scientific quality, consistency and data gaps. 相似文献