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141.
This study was carried out in 32 communities neighbouring four Ramsar wetlands in Northern Greece. In particular, it concerns the study of local residents' attitude regarding the ways of management and exploitation of the wetlands and their sociological features, using the opinion poll method (1600 questionnaires were distributed). The aim of this investigation is the evaluation of findings for planning of effective management and conservation policy of wetlands, incorporating the opinions of local residents. Further protection of the wetlands, awareness of local residents of the value of wetlands, tourism or agriculture development (in some cases), as well as more governmental support, became obvious results from this research.  相似文献   
142.
143.
Workers (n = 17 275) from 14 European Union (EU) member states provided data on job control, job dissatisfaction, perceived risk of occupational stress, and absence. For each state, level of research and development (R&D) activity was assessed. Associations between individual levels of control and occupational health were stronger where national R&D activity was higher. The moderation occurred for individuals' levels of control in relation to job dissatisfaction, perceived risk of occupational stress, and absence. The findings with job dissatisfaction and absence were replicated in a sample of workers from 10 Eastern European former Communist countries (n = 7926). Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
144.
This paper presents a methodology for the calculation of atmospheric stability classes in correlation with wind velocities for six sites of the Greek territory, namely Ellinikon (Athens), Elefsis, Megara, Heraklion, Chania and Patras, based on real data obtained from meteorological observations in these sites and on computations related with their geographic position. In addition to that, a comparison is presented of the atmospheric stability classes produced with online measurements for the Ellinikon (Athens) site with significant coincidence in the results.

These calculated values of the meteorological parameters (particularly of atmospheric stability) are most appropriate for uncertainty calculations in quantified risk assessments (QRAs) of hazardous installations sited in the above-mentioned areas, especially when risk and safety-related decisions need to be taken. Consequent results obtained with these parameters are more realistic compared to the “classical” assumption of D5/F2, which leads to significant diversification in the estimation of risk.  相似文献   

145.
Hexachlorocyclohexane (HCH) and lindane were used as insecticides since 1949s. They were progressively banished in most of the nations in the world, because of the their persistence and their potential toxicity and carcinogenicity. They are still occurring in the environment. These insecticides and isomers (α-HCH, β-HCH…) were detected in all media, e.g. soils, sediments, potable water, vegetables, human and animal tissues and air. In this review, we present the synthesis of the analytical procedures and materials used to determine the HCHs isomers in media such as vegetables, human tissues, animals tissues and rations. The analytical techniques which are presented permit to select the best analytical conditions to detect HCHs isomers.  相似文献   
146.
Composts fractions were extracted by water from composts at the beginning and at the end of the composting process. These water extracts were characterized by elementary analysis and spectroscopies, and then, tested for their capacity to photosensitize the degradation of three aromatic compounds: Irgarol, fenuron, and 2,4,6-trimethylphenol. In solar light, the water extracts (25 mg/l) were found to completely degrade 2,4,6-trimethylphenol after 24 h, and afford a transformation of fenuron and Irgarol of 25% and 18%, respectively.An erratum to this article can be found at  相似文献   
147.
Alfalfa plants were grown in soil-pots contaminated with a mixture of Cd(II), Cu(II), Ni(II), and Zn(II), (at 50 mg/kg each) at pHs of 4.5, 5.8, and 7.1. The plants were fertilized using a nutrient solution, which was adjusted appropriately to the same pH. Plants in the control treatment were grown in the absence of the heavy metals mixture. The growth of the control plants was the same at the three pHs studied and the heavy metal stressed plants also showed similar behavior at each pHs. There were statistically significant differences (P<0.05) between the shoot length of the control treatment plants and the length of plants grown in the presence of the heavy metal mixture. Under the effects of the heavy metal mixture, nickel was the most accumulated element in the shoot tissue, with 437, 333, and 308 ppm at pH 7.1, 5.8, and 4.5, respectively. Cadmium was found to be second in accumulated concentrations with 202 ppm, 124 ppm, and 132 ppm at pH 7.1, 5.8, and 4.5, respectively, while zinc was third, followed by copper. The maximum relative uptakes (element in plant/element in soil-water-solution) were found to be 26 times for nickel, 23 times for cadmium, 12 times for zinc. and 6 times for copper. We considered these relations as indicative of the ability of alfalfa plants to take up elements from a soil matrix contaminated with a mixture of cadmium, copper, nickel, and zinc.  相似文献   
148.
Laboratory tests with generated aerosols were conducted to test the efficacy of two recent design modifications to the well-established tapered element oscillating microbalance (TEOM) continuous particulate matter (PM) mass monitor. The two systems tested were the sample equilibration system-equipped TEOM monitor operating at 30 degrees C, which uses a Nafion dryer as part of the sample inlet, and the differential TEOM monitor, which adds a switched electrostatic precipitator and uses a self-referencing algorithm to determine "true PM mass." Test aerosols included ammonium sulfate, ammonium nitrate, sodium chloride, copper (II) sulfate, and mixed aerosols. Aerosols were generated with an atomizer or a vibrating orifice generator and were equilibrated in a 450-L slow flow chamber before being sampled. Relative humidity in the chamber was varied between 10 and 90%, and step changes in humidity were executed while generating aerosol to test the response of the instruments. The sample equilibration system-equipped TEOM monitor does reduce, but not totally eliminate, the sensitivity of the TEOM mass monitor to changes in humidity. The differential TEOM monitor gives every indication of being a very robust technique for the continuous real-time measurement of ambient aerosol mass, even in the presence of semi-volatile particles and condensable gases.  相似文献   
149.
Twenty ropes with 400 Perna perna mussels seeds (3 cm shell size) were set-up on floating structures at Cabo Frio Island, Arraial do Cabo, approximately 100 km northeast of Rio de Janeiro city. A rope was taken out on a monthly basis, and the shell sizes of 100 seeds were measured. The haemolymph of 10 male and 10 female individuals was taken, and the same individuals were separated for 210Po/210Pb determination. After one year of monthly sampling, no clear correlation was observed between the 210Po concentration, mussel's age and weight. A mean 210Po concentration of 155 Bq kg(-1) wet weight basis, was obtained, which is comparable with data reported in the literature. The radiation dose did not have any observable effect on the micronuclei frequency and DNA breaks in the mussels. This was probably due to the low dose rate, 0.02 mGy d(-1), in comparison with the suggested potential dose limit of 10 mGy d(-1).  相似文献   
150.
Evolutionary biologists are increasingly relying on ancient DNA from archaeological animal bones to study processes such as domestication and population dispersals. As many animal bones found on archaeological sites are likely to have been cooked, the potential for DNA preservation must be carefully considered to maximise the chance of amplification success. Here, we assess the preservation of mitochondrial DNA in a medieval cattle bone assemblage from Coppergate, York, UK. These bones have variable degrees of thermal alterations to bone collagen fibrils, indicative of cooking. Our results show that DNA preservation is not reliant on the presence of intact collagen fibrils. In fact, a greater number of template molecules could be extracted from bones with damaged collagen. We conclude that moderate heating of bone may enhance the retention of DNA fragments. Our results also indicate that ancient DNA preservation is highly variable, even within a relatively recent assemblage from contexts conducive to organic preservation, and that diagenetic parameters based on protein diagenesis are not always useful for predicting ancient DNA survival.  相似文献   
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