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181.
This study describes three couples a t risk for homozygous β-thalassaemia in which one of the partners carried a short deletion β-thalassaemia defect. Detection of short deletions in trophoblast DNA was accomplished by the very simple procedure of non-denaturing polyacrylamide gel electrophoresis. This method may be applied to detect β-thalassaemia mutations due to deletion or addition of more than two nucleotides.  相似文献   
182.
GOAL, SCOPE AND BACKGROUND: Ozone is the most important air pollutant in Europe for forest ecosystems and the increase in the last decades is significant. The ozone impact on forests can be calculated and mapped based on the provisional European Critical Level (AOT40 = accumulated exposure over a threshold of 40 ppb, 10,000 ppb x h for 6 months of one growing season calculated for 24 h day(-1)). For Norway spruce, the Austrian main tree species, the ozone risk was assessed in a basis approach and because the calculations do not reflect the health status of forests in Austria, the AOT40 concept was developed. METHODS: Three approaches were outlined and maps were generated for Norway spruce forests covering the entire area of Austria. The 1st approach modifies the AOT40 due to the assumption that forests have adapted to the pre-industrial levels of ozone, which increase with altitude (AOTalt). The 2nd approach modifies the AOT40 according to the ozone concentration in the sub-stomata cavity. This approach is based on such factors as light intensity and water vapour saturation deficit, which affect stomatal uptake (AOTsto). The 3rd approach combines both approaches and includes the hemeroby. The pre-industrial ozone level approach was applied for autochthonous ('natural') forest areas, the ozone-uptake approach for non-autochthonous ('altered') forest areas. RESULTS AND DISCUSSION: The provisional Critical Level (AOT40) was established to allow a uniform assessment of the ozone risk for forested areas in Europe. In Austria, where ozone risk is assessed with utmost accuracy due to the dense grid of monitoring plots of the Forest Inventory and because the continuously collected data from more than 100 air quality measuring stations, an exceedance up to the five fold of the Critical Level was found. The result could lead to a yield loss of up to 30-40% and to a severe deterioration in the forest health status. However, the data of the Austrian Forest Inventory and the Austrian Forest Damage Monitoring System do not reflect such an ozone impact. Therefore, various approaches were outlined including the tolerance and avoidance mechanisms of Norway spruce against ozone impact. Taking into consideration the adaptation of forests to the pre-industrial background level of ozone, the AOT40 exceedances are markedly reduced (1st approach). Taking into account the stomatal uptake of ozone, unrealistic high amounts of exceedances up to 10,000 ppb x h were found. The modelled risk does not correspond with the health status and the wood increment of the Austrian forests (2nd approach). Consolidating the forgoing two approaches, a final map including the hemeroby was generated. It became clear that the less natural ('altered') forested regions are highly polluted. This means, that more than half of the spruce forests are endangered by ozone impact and AOT40 values of up to 30,000 ppb x h occur (3rd approach). CONCLUSIONS: The approaches revealed that a plausible result concerning the ozone impact on spruce forests in Austria could only be reached by combining pre-industrial ozone levels, ozone flux into the spruce needles and the hemeroby of forests.  相似文献   
183.
In this study, we investigate the feasibility of developing a new behavioural toxicity bioassay (Swimming Speed Alteration test—SSA test) with larvae of Balanus amphitrite (Crustacea Cirripedia). This organism was chosen as a model for different reasons: it is present all over the world, simple to be reared, easily available, and also because barnacles play an important role in the coastal ecosystem. In addition, all the operations related to the rearing and test execution are comparatively cheap. This bioassay was performed with several classes of chemical pollutants (antifouling biocides, neurotoxic pesticides, and heavy metals) and with environmental samples (sediment elutriates). The measurement of swimming speed, by means of video-graphic techniques, proved to be a valid instrument in highlighting the sub-lethal levels of toxicity caused by the different tested samples. In conclusion, the SSA test is able to provide in a biomonitoring program a good behavioural integrated output, which is also repeatable, sensitive, easily interpretable, and truly representative of a broad range of toxic compounds and environmental toxic matrices which are, generally, very complex and difficult to analyse. For all of these reasons, it could be proposed as a non-specific behavioural end-point. Physical and Chemical Impacts on Marine Organisms, a Bilateral Seminar Italy-Japan held in November 2004.  相似文献   
184.
Cytogenetic data about 145 chorionic villus samples obtained between the 13th and 35th week of gestation are reported. ‘Late’ chorionic villus sampling (CVS) was used to resolve different situations: failed amniotic fluid cell cultures (5 cases); confirmation of an abnormal karyo-type, previously diagnosed as mosaic (14 cases); and ultrasound fetal malformation (23 cases). Most of the samples (103 cases) were analysed for the classical indications and in these cases, the principal aim was to obtain a rapid fetal karyotype. Excluding the cases used to check fetal karyotype, a chromosomal aberration was found in 11 out of 131 biopsies. In four cases of the group in which the fetal karyotype was checked (14 cases), the pathology observed at the first diagnosis was confirmed, while in the remaining ten cases the anomaly was not observed.  相似文献   
185.
Gardening has become a relevant contributor to the quality of life of suburbanites, as a source of leisure, to build a relationship with nature or to express a particular social identity. Nevertheless, water scarcity in the Mediterranean region has increased concerns about how demand should be managed to face future uncertainties, and watering the gardens has become an element for discussion in urban planning. This contribution presents the findings of a survey of permanent residents and secondary homeowners (n?=?230) in the suburban areas surrounding the city of Girona in the northeast of Catalonia (Spain). The area is a popular national and international tourist destination and a preferred place for second-home owners. We explore the main socio-demographic drivers for choosing an alternative watering source and we analyse if water-harvesting tank sizes properly meet net irrigation requirements. Results show that many water-harvesting tanks are oversized. The percentage of unemployed or retired household members, the estimated irrigation water needs of the garden and the education level directly influence the search for alternative sources of water. Moreover, social variables like interest in gardening, water conservation attitudes and household income indirectly influence the search for alternative sources of water.  相似文献   
186.
This paper investigates a techno-economic analysis on small and medium scales: 50 kilo tonnes per annum (ktpa) and 100 ktpa combustion plants with steam turbine technology utilising solid recovered fuel (SRF). Energy and efficiency calculations for the technical assessment are performed. The economic viability of the two processes is investigated through a discounted cash flow analysis. The levelised cost is used to calculate the cost of production of one unit of electricity. A life cycle assessment (LCA) of the 100 ktpa scale SRF plant is performed, where the foundations of LCA calculations reside in energy calculations carried out for the technical analysis. Life cycle inventories were developed using inventory analysis and impact assessment. The results of the LCA are compared with those from equivalent scale coal, natural gas and electricity-mix plants. The LCA is also compared with a landfill reference system. Both scales are economically and technically viable. The SRF plant has a lower global warming potential emission (EGWP) compared with the coal, natural gas and electricity-mix plants and the reference landfill system.  相似文献   
187.
 Relative and absolute growth were studied in 17 species of deep-water decapod crustaceans, spanning nine families of six different infra-orders, in the Northwestern Mediterranean Sea. The overall maximum abundance of these species lay between 200 m and 750 m (i.e. upper- and mid-slope species). Relative and absolute growth rates were compared by contrasting the slopes of the size–weight relationships for the different species and calculating the von Bertalanffy growth-equation parameters asymptotic length (L ) and growth rate (k). The size–weight relationships differed significantly as function of the species' life habits. The results revealed a significant decrease in weight relative to size in mesopelagic species (which carry out diel vertical migrations), an almost isometric relationship between size and weight in the less mobile nektobenthic species, and a significant increase in weight relative to size in strictly benthic species. The mean allometric coefficient for each group increased significantly from mesopelagic to benthic species. However, no general trend was observed in the growth-performance index, Φ (an index used to compare absolute growth rates between species, as a function of habit and depth of maximum abundance for all species combined), suggesting that the deep-water decapod crustaceans studied have similar absolute growth rates. Nevertheless, comparison of growth-parameter and growth-performance index values within families did reveal differences. Mesopelagic species of the families Sergestoidae and Pasiphaeidae showed slightly increased growth rates with increasing depth of distribution. Nektobenthic species of the genus Plesionika followed a trend opposite to that shown by mesopelagic species, with a higher growth rate for the shallowest-dwelling species (P. heterocarpus) than the deepest-dwelling species (P. acanthonotus). Taking growth as one of the major components of an organism's energy budget, the growth rates for the decapod crustacean species in this study were significantly lower than those reported in the literature for shallow-water penaeid crustacean species (which are distributed in higher-temperature habitats than deep-water Mediterranean crustaceans) and higher than those reported for mesopelagic myctophid fish species. Hence, the well-defined growth trends shown by deep-water decapod crustacean species in the Northwestern Mediterranean Sea, compared to the less well-defined trends in the other taxa, is discussed in the framework of the overall dynamics of their ecosystem. Received: 25 May 1998 / Accepted: 27 September 1999  相似文献   
188.
Sulfonamides (SAs) have become one of the antibiotic families most frequently found in all kind of environmental waters. In the present work, the presence of 16 SAs and one of their acetylated metabolites in different water matrices of the Ebro River basin has been evaluated during two different sampling campaigns carried out in 2007 and 2008. Influent and effluent samples from seven wastewater treatment plants (WWTPs), together with a total of 28 river water samples were analyzed by on-line solid phase extraction-liquid chromathography-tandem mass spectrometry (on-line SPE-LC-MS/MS). Sulfamethoxazole and sulfapyridine were the SAs most frequently detected in WWTPs (96-100%), showing also the highest concentrations, ranging from 27.2 ng L(-1) to 596 ng L(-1) for sulfamethoxazole and from 3.7 ng L(-1) to 227 ng L(-1) for sulfapyridine. Sulfamethoxazole was also the SA most frequently detected in surface waters (85% of the samples) at concentrations between 11 ng L(-1) and 112 ng L(-1). In order to assess the effectiveness of the wastewater treatment in degrading SAs, removal efficiencies in the seven WWTPs were calculated for each individual SA (ranging from 4% to 100%) and correlated to the corresponding hydraulic retention times or residence times of the SAs in the plants. SAs half-lives were also estimated, ranging from to 2.5 hours (sulfadimethoxine) to 128 h (sulfamethazine). The contribution of the WWTPs to the presence of SAs depends on both the load of SAs discharging on the surface water from the WWTP effluent but also on the flow of the receiving waters in the discharge sites and the dilution exerted; WWTP4 exerts the highest pressure on the receiving water course. Finally, the potential environmental risk posed by SAs was evaluated calculating the hazard quotients (HQ) to different non-target organisms in effluent and river water. The degree of susceptibility resulted in algae>daphnia>fish. Sulfamethoxazole was the only SA posing a risk to algae in effluent water, with an HQ>7.  相似文献   
189.
The presence of sewage-borne micro contaminants in environmental waters is directly related to the discharge of treated effluents from wastewater treatment plants (WWTP) and the flow rate of the receiving river waters. Mediterranean rivers, in particular, are characterized by important fluctuations in the flow rates and heavy pollution pressures resulting from extensive urban, industrial and agricultural activities. This translates into contamination levels in these rivers often higher than those in other larger European basins. The present work provides an overview of the occurrence of five groups of organic contaminants (131 compounds) namely pharmaceuticals, illicit drugs, polar pesticides, estrogens, alkylphenols and related ethoxylates in WWTP tertiary treatment effluents. Data gathered during a period of water reuse carried out in the lower stretch of the Llobregat river (NE Spain), in the surroundings of the town of Barcelona as a consequence of the severe drought that took place along the years 2007-2008 are presented as illustrative example. In general, measured concentrations of the target compounds were in the low to mid ng L−1 range. The total concentration of each compound class downstream to the discharge point was similar or slightly higher than that found upstream. Regarding the loads calculated for each compound, the relative contribution from the river upstream and the tertiary effluent were highly compound depending with no apparent trend. However, estimation of the overall bulk loads for each compound class determined in the Llobregat river showed the following rank order: pharmaceuticals > alkylphenols > pesticides > illicit drugs ? estrogens.  相似文献   
190.
The extent of social acceptance of carbon capture and storage (CCS) is likely to significantly influence the sustainable development of CO2 storage projects. Acceptance of CCS by the key stakeholders (policy makers, the general public, the media and the local community), linked to specific projects, as well as how the technology is communicated about and perceived by the public, have become matters of interest for the social sciences. This article reports on an investigation of the public perception of CCS technology in Spain. Individuals’ views on CCS are analysed through focus groups with lay citizens using “stimulus materials”. As the analysis shows, lay views of CCS differ significantly from the views of decision-makers and experts. Public concerns and reactions to CCS technology and potential projects, as well as the degree of consensus on its acceptance or rejection are detailed. Implications for the future use of CCS are discussed.  相似文献   
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