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591.
592.
Over the last years, the obviously increasing, hormone-dependent impairments observed in humans and animals, as well as the increased occurrence of hormone-dependent types of cancer, are sometimes associated with environmental chemicals which are suspected to imitate or block the effects of natural hormones. For a variety of environmental chemicals an endocrine efficacy could already be demonstrated. Little is known, however, about a possible hormonal activity of plant protection agents which are at present certificated in the Federal Republic of Germany. The aim of the present study was the in vitro testing of at least 57 active ingredients of pesticides and growth regulators certificated in the Federal Republic of Germany, for their possible estrogenic activity. The E-Screen-Assay based on the human breast cancer cell line MCF-7 was used as the suitable test system. For at least 8 of the tested substances, an receptor-mediated estrogenic activity could be shown in vitro. With the exception of one substance, 7 active ingredients displayed a very weak affinity for the human estrogen receptor. Their ability to displace 17β-estradiol from the receptor was low. Only the herbicide Pendimethalin is to be classified as a full estrogen receptor agonist; it is able to displace 17β-estradiol almost completely from the receptor. Howeverm the estrogenic potency of Pendimethalin, in comparison to 17β-estradiol, was seen to be as small as the estrogenic potency of the other 7 substances tested positively in the E-Screen-Assay. Among this 7 substances, two could not be classified as estrogenically active anymore, because their affinity to the human estrogen receptor was too weak. The relevance of the available results for livng organisms should be clarified in further in vivo investigations.  相似文献   
593.
The shores of many Central European lakes located in the hinterland of large conurbations are heavily endangered by intensive settlement, traffic, sewage input, manipulation of the water level, tourism and recreation. This increasing impact has negatively affected the function of the lake shore in respect to conservation and species protection, to water protection and its importance for recreation. This paper describes the overlap of the multiple uses and the precautions planned since 1981 on the national and international level to guarantee the essential multiple functionality, e.g. as drinking water reservoir for the conurbations in the northern part of Baden-Württemberg, as supraregional centre for water sports and tourism, and as an important environment for endangered plant and animal species. Management measures include regional planning as well as the international water protection and preservation with many contributions from non governmental international organisations Given a high agreement concerning these aims, many indispensable actions could successfully be realised on the political and administrative level. On the basis of 14 topics we follow the development since 1981, most recently also driven by the EU (FFH/Natura 2000), Water framework directive). Backlogs became obvious for four topics: 1. The lack of efficient reviews on completed measures, 2. gaps in basic understanding, 3. The dragging harmonisation of an intergrated shore protection program across the borders, and 4. the lack of concepts for a sustainable development including plans for monitoring.  相似文献   
594.
Chemically modified pullulan was evaluated for its sorption efficiency and selectivity to remove cadmium(Cd) from spiked high-hardness groundwater(GW). Pullulan esterified with succinic anhydride using dimethylaminopyridine showed a fairly high degree of substitution value as confirmed by1 H NMR spectroscopy. Pullulan succinate(Pull-Suc) was converted into the sodium salt(Pull-Suc-Na). The effect of contact time(5–200 min) and p H(2–8) on Cd-uptake by the sorbent(Pull-Suc-Na) was investigated. The sorbent showed more than 90% Cd-removal in first 15 min from distilled water(DW) and GW solution,respectively. Comparison of Pull-Suc-Na with other polysaccharidal sorbents suggested its high efficiency(DW 476.2 mg/g and GW 454.5 mg/g) and selectivity for the removal of Cd by an ion exchange mechanism, which is further supported by the negative Gibbs free energy values calculated from Langmuir isotherms. A Langmuir isotherm kinetic model provided the best fit for the sorption of Cd using Pull-Suc-Na. The sorbent showed a negligible decrease in Cd-uptake over three regeneration cycles. The thermal stability testing of the sorbents indicated that Pull-Suc-Na(sorbent) is more stable than Pull-Suc.  相似文献   
595.
An experimental group of homing pigeons (Columba livia f. domestica) learned to associate food with a magnetic anomaly produced by bar magnets that were fixed to the bowl in which they received their daily food ration in their home loft; the control group lacked this experience. Both groups were trained to search for two hidden food depots in a rectangular sand-filled arena without obvious visual cues; for the experimental birds, these depots were also marked with three 1.15 × 106 μT bar magnets. During the tests, there were two food depots, one marked with the magnets, the other unmarked; their position within the arena was changed from test to test. The experimental birds searched within 10 cm of the magnetically marked depot in 49% of the test sessions, whereas the control birds searched there in only 11% of the sessions. Both groups searched near the control depot in 11 and 13% of the sessions, respectively. The significant preference of the magnetically marked food depot by the experimental birds shows that homing pigeons cannot only detect a magnetic anomaly but can also use it as a cue for locating hidden food in an open arena.  相似文献   
596.
Depending on gender and activity, overcrowding and safety concerns may detract from urban green space use. Differences in use displacement intentions from a recreational trail in a forest in Vienna were investigated for male and female walkers as well as male and female dog-walkers (N = 425) using an image-based stated preference model. The trail scenarios were depicted as digitally calibrated images that systematically displayed combinations of levels of crowding with different mixes of user types and visitor behaviour. Visitors were asked whether the presented recreation scenario was so unacceptable that they would shift their use away from the presented trail. Hours and days of stated non-use of the recreation trail by various user groups are estimated by integrating the results of the behavioural model with annual visitation data. Use displacement intentions differed by gender and activity. High use levels were a greater concern for all respondents than very low use levels, particularly for female dog-walkers. However, only a small proportion of the recorded hours were heavily used. Safety concerns about very low use levels reduced the potential times of forest use for female walkers without a dog.  相似文献   
597.
In the HYENA study (HYpertension and Exposure to Noise near Airports) noise annoyances due to aircraft and road traffic noise were assessed in subjects that lived in the vicinity of 6 major European airports using the 11-point ICBEN scale (International Commission on Biological Effects of Noise). A distinction was made between the annoyance during the day and during the night. Lden and Lnight were considered as indicators of noise exposure. Pooled data analyses showed clear exposure–response relationships between the noise level and the noise annoyance for both exposures. The exposure–response curves for road noise were congruent with the EU standard curves used for predicting the number of highly noise annoyed subjects in European communities. Annoyance ratings due to aircraft noise, however, were higher than predicted by the EU standard curves. The data supports other findings suggesting that the people's attitude towards aircraft noise has changed over the years, and that the EU standard curve for aircraft noise should be modified.  相似文献   
598.
Zusammenfassung  Sedimente spielen eine wichtige Rolle für die Funktionen aquatischer ?kosysteme, fungieren aber auch als Senke, Speicher und Quelle für lipophile Schadstoffe und Metalle. Wirkungsorientierte Analytik (EDA) ist ein geeignetes Werkzeug, um besonders problematische Stoffe zu identifizieren. Um Missinterpretationen und falsche Priorit?tensetzung zu vermeiden, sollte dabei neben den eigentlichen Effekten die Bioverfügbarkeit berücksichtigt werden. Bioverfügbarkeit wird dabei als komplexer Prozess betrachtet, der letztendlich dazu führt, dass ein bisher partikelgebundenes Molekül am Wirkort im Organismus ankommt und dort Sch?den verursachen kann. Um diesen Prozess in der EDA operativ berücksichtigen zu k?nnen, kann er in mehrere Teilprozesse zerlegt werden. Dies beinhaltet die Desorption vom Sediment und damit die biologische Zug?nglichkeit, die Gleichgewichtsverteilung desorbierbarer Stoffe zwischen Sediment, Porenwasser und Organismus entsprechend der Aktivit?t in den verschiedenen Phasen und die toxikologische Bioverfügbarkeit als Resultat toxikokinetischer Prozesse wie Resorption, Transport, Metabolisierung und Ausscheidung. Die biologische Zug?nglichkeit als Resultat der Desorptionskinetik l?sst sich durch den Einsatz milder Extraktionsverfahren z. B. mit TENAX in die EDA einbeziehen. Die Gleichgewichtsverteilung im System Sediment-Wasser-Organismus kann durch verteilungsbasierte Dosierung simuliert werden. Erste Ergebnisse mit diesen Verfahren zeigen, dass bei Einbeziehung von Bioverfügbarkeit polare Sedimentkontaminanten relativ zu klassischen unpolaren Problemstoffen wie Polyzyklischen Aromatischen Kohlenwasserstoffen deutlich an Bedeutung gewinnen. Verantwortliche Herausgeber: Jan Schwarzbauer · Peter Heininger · Evelyn Claus  相似文献   
599.
The aim of environmental surveillance is to monitor known phenomena as well as to detect exceptional situations. Synoptic monitoring of large areas in coastal waters can be performed by remote sensing using multispectral sensors onboard satellites. Many methods are in use which enable the detection and quantification of ‘standard algae’ or specific algae blooms using their known spectral response. The present study focusses on the detection of spectra outside the known range and which are referred to as exceptional spectra. In a first step observations from a one-year period were used to establish the parameterisation of what is defined as ‘normal.’ In a second step observations from a different period were used to test the novelty detection application, i.e. to look for features not occurring in the first period.   相似文献   
600.
Air pollution is increasingly recognized as a significant contributor to global health outcomes. A methodological framework for evaluating the global health-related outcomes of outdoor and indoor (household) air pollution is presented and validated for the year 2005. Ambient concentrations of PM2.5 are estimated with a combination of energy and atmospheric models, with detailed representation of urban and rural spatial exposures. Populations dependent on solid fuels are established with household survey data. Health impacts for outdoor and household air pollution are independently calculated using the fractions of disease that can be attributed to ambient air pollution exposure and solid fuel use. Estimated ambient pollution concentrations indicate that more than 80% of the population exceeds the WHO Air Quality Guidelines in 2005. In addition, 3.26?billion people were found to use solid fuel for cooking in three regions of Sub Saharan Africa, South Asia and Pacific Asia in 2005. Outdoor air pollution results in 2.7?million deaths or 23?million disability adjusted life years (DALYs) while household air pollution from solid fuel use and related indoor smoke results in 2.1?million deaths or 41.6?million DALYs. The higher morbidity from household air pollution can be attributed to children below the age of 5 in Sub Saharan Africa and South Asia. The burden of disease from air pollution is found to be significant, thus indicating the importance of policy interventions.  相似文献   
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