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41.
Foods and feeds were analyzed during the period of 2007–2014 employing validated and accredited methods based on gas chromatography–high-resolution mass spectrometry. Sampling has been carried out in-line with national monitoring programs as well as during import controls into Lithuania. Food samples such as eggs, milk, beef, pork, poultry, fats of plant and animal origin, fish, cod liver, and feed samples such as premixes, feeds of plant origin, compound feed, mineral feed, vegetable oil, and fish meals were analyzed. Most of the samples exhibited concentrations below maximum limits, except cod liver. Health impacts were assessed in respect to human daily intakes. Data between groups are compared.  相似文献   
42.
Twenty microfungal isolates were collected from diseased fruiting bodies of Agaricus bisporus sampled from Serbian mushroom farms during 2003–2007. Based on morphological characteristics and pathogenicity tests, the isolates were identified as Cladobotryum dendroides. The isolates of C. dendroides and A. bisporusF56 and U3 were tested for sensitivity to several selected fungicides in vitro. C. dendroides isolates were found to be more sensitive to prochloraz manganese and flusilazole + carbendazim than to the other fungicides tested (EC50 values were 0.09 and 0.11 mg L? 1, respectively) and weakly resistant to thiophanate-methyl (EC50 values ranged between 6.53 and 12.09 mg L? 1). Selectivity indexes of the tested fungicides on both C. dendroidesand A. bisporusindicated that thiophanate-methyl, cyproconazole + carbendazim and flusilazole + carbendazim had much less selective fungitoxicity than benomyl, carbendazim and prochloraz manganese.  相似文献   
43.
The specific activities of natural radionuclides ((40)K, (226)Ra and (232)Th) and Chernobyl-derived (137)Cs were measured in soil profiles representing typical soil types of Belgrade (Serbia): chernozems, fluvisols, humic gleysols, eutric cambisols, vertisols and gleyic fluvisols. The influence of soil properties and content of stable elements on radionuclide distribution down the soil profiles (at 5 cm intervals up to 50 cm depth) was analysed. Correlation analysis identified associations of (40)K, (226)Ra and (137)Cs with fine-grained soil fractions. Significant positive correlations were found between (137)Cs specific activity and both organic matter content and cation exchange capacity. Saturated hydraulic conductivity and specific electrical conductivity were also positively correlated with the specific activity of (137)Cs. The strong positive correlations between (226)Ra and (232)Th specific activities and Fe and Mn indicate an association with oxides of these elements in soil. The correlations observed between (40)K and Cr, Ni, Pb and Zn and also between (137)Cs and Cd, Cr, Pb and Zn could be attributed to their common affinity for clay minerals. These results provide insight into the main factors that affect radionuclide migration in the soil, which contributes to knowledge about radionuclide behaviour in the environment and factors governing their mobility within terrestrial ecosystems.  相似文献   
44.
A comprehensive study of various psychoactive substances and their metabolites was performed in the wastewater treatment plant of the city of Zagreb (780 000 inhabitants) using liquid chromatography/tandem mass spectrometry (LC-MS-MS). The estimation of drug abuse for five different illicit drugs, including heroin, cocaine, marijuana, amphetamine and ecstasy, was made on the basis of their representative excretion rates, which were determined over a period of 8 months. Marijuana (1000 kg/year), heroin (75 kg/year) and cocaine (47 kg/year) were found to be the most frequently consumed illicit drugs, while the consumption of amphetamine-type drugs was much lower (1-3 kg/year). A comparison with other reports indicated that drug abuse profiles in transition countries might be different from those reported for Western Europe, in particular with respect to the comparatively increased consumption of heroin. Enhanced consumption of stimulating drugs (cocaine and ectasy) was systematically detected during weekends.  相似文献   
45.
Influence of the economic criterion, called Profit, on the ranking of copper concentrates is investigated. Values of the criterion, which correspond to alternatives, are derived as earning values obtained by the exploitation of individual concentrates. Various scenarios with respect to the weight w 14, corresponding to the additional economical criterion, are defined and solved. A discrete set of results is generated, applying DECISION LAB software implementation of the PROMETHEE-GAIA methodology. Interpolating these results, we derived continuous interpolation functions which compute necessary quantities of concentrates for each real value of w 14 within the interval [0, 100].  相似文献   
46.
Once released into the aquatic environment, pharmaceuticals may undergo different degradation processes. Photodegradation, for example, might be an important elimination process for light-sensitive pharmaceuticals, such as antibiotics. In this study, the fate of sulfonamides (sulfamethazine, sulfadiazine, and sulfamethoxazole) and their N 4-acetylated metabolites (N 4-acetylsulfadiazine, N 4-acetylsulfamethazine, and N 4-acetylsulfamethoxazole) under simulated sunlight irradiation was investigated. The irradiation resulted in total or almost total degradation (88 to 98 %) of the pharmaceuticals tested, except for sulfamethazine (52 %), during 24 h of irradiation. The photoproducts of all investigated pharmaceuticals have been analyzed using high-performance liquid chromatography coupled to electrospray ionization tandem mass spectrometry. Structure elucidation performed from photodegradation products of both, sulfonamides and their N 4-acetylated metabolites, clearly showed two major formation pathways. These were cleavage of the sulfonamide bond as well as SO2 extrusion. In total, nine photoproducts were elucidated. Among these photoproducts, the tautomers of sulfamethoxazole and desulfonated products of sulfadiazine and sulfamethazine were also present. Tautomers of sulfadiazine and sulfamethazine have been characterized here for the first time as well as some photoproducts of sulfadiazine, sulfametoxazole, and their metabolites N 4-acetylsulfadiazine and N 4-acetylsulfametoxazole. The obtained results are an important piece in the complex puzzle for assessing the environmental fate of sulfonamides and their metabolites in the environment.  相似文献   
47.
The gas-phase ozonolysis of (E)-β-farnesene was investigated in a 3.91 m3 atmospheric simulation chamber at 296 ± 2 K and relative humidity of around 0.1%. The relative rate method was used to determine the reaction rate coefficient of (4.01 ± 0.17) × 10?16 cm3 molecule?1 s?1, where the indicated errors are two least-squares standard deviations and do not include uncertainties in the rate coefficients for the reference compounds (γ-terpinene, cis-cyclooctene and 1,5-cyclooctadiene). Gas phase carbonyl products were collected using a denuder sampling technique and analyzed with GC/MS following derivatization with O-(2,3,4,5,6-pentafluorobenzyl) hydroxylamine (PFBHA). The reaction products detected were acetone, 4-oxopentanal, methylglyoxal, 4-methylenehex-5-enal, 6-methylhept-5-en-2-one, and (E)-4-methyl-8-methylenedeca-4,9-dienal. A detailed mechanism for the gas-phase ozonolysis of (E)-β-farnesene is proposed, which accounts for all of the products observed in this study. The results of this work indicate that the atmospheric reaction of (E)-β-farnesene with ozone has a lifetime of around 1 h and is another possible source of the ubiquitous carbonyls, acetone, 4-oxopentanal and 6-methylhept-5-en-2-one in the atmosphere.  相似文献   
48.
The relationship between whole effluent toxicity (WET) and chemical-based effluent quality assessment across a range of effluent types was examined for the first time in Serbia. WET was determined by Daphnia magna acute tests, while chemical-based toxicity was taken as theoretical for concentrations of priority chemicals and effluent quality assessment based on the valid Serbian regulations. A poor correlation was found between WET and chemical-based effluent quality assessment: positive toxicity tests were found, in general, in cases where samples satisfied the requirements of mandatory effluent monitoring. Statistically insignificant correlation between the predicted and observed toxicity indicated that the presence of priority substances accounted to the overall toxicity only to a certain degree, most probably due to a rather short list of priority pollutants regularly analysed in effluents. Current monitoring requirements neglect hazards that derive from potentially present toxicants and unpredictable toxicity of complex mixtures, which led to poor correlation between the WET and chemical-based results in this study.  相似文献   
49.
This study presents the phenology of two common Mediterranean sponges belonging to the genus Oscarella (Porifera, Homoscleromorpha). Oscarella tuberculata and Oscarella lobularis are two sibling species, dwellers of shallow benthic communities which tend to have distinct ecological behavior, respectively, euryecious and rather stenoecious. The comparative study of their reproductive cycle showed that both Oscarella species have a seasonal reproductive cycle with a successive phase duration differing from one species to another. In both species, there is a continuous oogenesis, with new oocytes appearing in spring, whereas the spermatogenesis generally starts later with the early warming of the sea. The embryonic development and the larval release are restricted to the warmest months of the year. We also observed a shift in the period of gametogenesis and larval emission depending on species and differences in their sensitivity to changes in thermal regime. It appears that an increase in seawater temperature can affect sex determination, with mainly a shift toward males in both species. Their reproductive efforts are variable in time, and can be in some cases influenced by the temperature regime. This is especially the case of O. lobularis which seems to be the most thermosensitive, its phenology responding significantly to changes in thermal regime, whereas O. tuberculata seems to be less sensitive and/or reactive. By detecting phenological changes among sponges, this study demonstrated the relevance of such monitoring to assess the possible biological response to climate change.  相似文献   
50.
Acute respiratory infections are common in children below 5 years and recent studies suggest a possible link with air pollution. In this study, we investigated the association between ambient nitrogen oxides (NOx) and bronchitis or upper airway inflammation.This longitudinal study was conducted in Teplice and Prachatice districts, Czech Republic. Children were followed from birth to 4.5 years of age. Data were compiled from medical records at delivery and at follow up, and from self-administered questionnaires from the same two time points. Air pollution monitoring data were used to estimate exposure over five different averaging periods ranging from three to 45 days prior to an episode. To quantify the association between exposure and outcome, while accounting for repeated measure correlation we conducted logistic regression analysis using generalized estimating equations.During the first 2 years of life, the adjusted rate ratio for bronchitis associated with interquartile increase in the 30-day average NOx was 1.31 [95% confidence interval (CI): 1.07, 1.61] and for two to 4.5 year olds, it was 1.23 (95% CI: 1.01, 1.49). The 14-day exposure also had stable association across both age groups: below 2 years it was 1.25 (95% CI: 1.06, 1.47) and for two to 4.5 years it was 1.21 (95% CI: 1.06, 1.39). The association between bronchitis and NOx increased with child's age in the under 2 years group, which is a relatively novel finding.The results demonstrate an association between NOx and respiratory infections that are sufficiently severe to come to medical attention. The evidence, if causal, can be of public health concern because acute respiratory illnesses are common in preschool children.  相似文献   
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