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41.
Lükewille Anke Bertok Imrich Amann Markus Cofala Janusz Gyarfas Frantisek Johansson Matti Klimont Zbigniew Pacyna Elisabeth Pacyna Jozef 《Water, air, and soil pollution》2001,130(1-4):229-234
Primary particulate matter is emitted directly into the atmosphere from various anthropogenic and natural sources such as power plants (combustion of fossil fuels) or forest fires. Secondary particles are formed by transformation of SO2, NOx, NH3, and VOC in the atmosphere. They both contribute to ambient particulate matter concentrations, which may have adverse effects on human health. Health hazards are caused by small particulate size, high number of especially fine (< 2.5 µm) and ultra-fine (< 0.1 µm) particles and/or their chemical composition. As part of an integrated assessment model developed at IIASA, a module on primary particulate matter (PM) emissions has been added to the existing SO2, NOx, NH3 and VOC sections. The module considers so far primary emissions of total suspended particles (TSP), PM10 and PM2.5 from aggregated stationary and mobile sources. A primary PM emission database has been established. Country specific emission factors for stationary sources have been calculated within the module using the ash content of solid fuels. 相似文献
42.
Pukalskas A van Beek TA Venskutonis RP Linssen JP van Veldhuizen A de Groot A 《Journal of agricultural and food chemistry》2002,50(10):2914-2919
Extracts from aerial parts of sweet grass (Hierochloe odorata) were active DPPH free radical scavengers. The active compounds were detected in extract fractions using HPLC with on-line radical scavenging detection. After multistep fractionation of the extract, two new natural products possessing radical scavenging activity were isolated, and their structures were elucidated by NMR and MS. They were identified as 5,8-dihydroxybenzopyranone and 5-hydroxy-8-O-beta-D-glucopyranosyl-benzopyranone. Activities of the compounds isolated were tested by DPPH and ABTS free radical scavenging assays, and compared with the known natural antioxidant rosmarinic acid and Trolox. 相似文献
43.
Johannes Charlier Pierre Dorny Bruno Levecke Janina Demeler Georg von Samson-Himmelstjerna Johan Hglund Jozef Vercruysse 《Research in veterinary science》2011,90(3):451-456
The serum pepsinogen level is widely accepted as a useful parameter for monitoring gastrointestinal nematode infections in first-season grazing calves. However, several aspects, with possible implications for its practicality and the way to use the pepsinogen test, have received little attention to date. The objectives of this study were to evaluate (1) the reproducibility of a pepsinogen assay; (2) the required sample size for a reliable diagnosis and (3) the compliance to and effect of advice based on pepsinogen levels determined in year one on the nematode infection levels in the next generation of calves. Despite a high repeatability of the pepsinogen assay within the reference lab, the reproducibility between different labs was poor. There was more variation in pepsinogen levels between herds than between animals within a herd, suggesting that it is most useful to make a herd level diagnosis. Sample size calculation indicated that sampling seven animals sufficed to obtain a reliable indication of calf groups of up to 40 animals. Eighty-two herds were followed-up over two consecutive years and 39 (48%) had followed the advice that was formulated based on pepsinogen levels. Thirty-nine percent of the herds were advised to reduce the intensity of chemoprophylaxis. Samples from animals of those herds showed a higher pepsinogen level in the second year, but none of them had a mean pepsinogen level that is considered excessive. It is concluded that pepsinogen determination at housing from a limited number of animals can contribute to the design of the anthelmintic control strategy in the next year and a more targeted use of anthelmintics. However, more efforts are needed to harmonize the assay between veterinary diagnostic labs. 相似文献
44.
Jozef Kov��?ik Bo?ivoj Klejdus Josef Hedbavny Pavol M��rtonfi Franti?ek ?tork Lenka M��rtonfiov�� 《Water, air, and soil pollution》2011,218(1-4):681-691
Selected physiological parameters and copper uptake by three chamomile (Matricaria chamomilla) cultivars (two tetraploid????Lutea?? and ??Unknown?? and one diploid????Novbona??) exposed to 60 ??M Cu over 7 days were studied. Genome size was 10.6 and 5.5 pg DNA/2C and chromosome number 2n?=?36 and 2n?=?18 in tetraploids and diploid, respectively. Root tissue water content and dry biomass were more reduced in diploid cultivar. Soluble proteins were depressed by Cu excess in all cultivars without respect to ploidy. Lignin accumulation and cinnamylalcohol dehydrogenase activity was the highest in Novbona. Phenylalanine ammonia-lyase activity was stimulated in tetraploid but reduced in diploid roots. Diploid contained higher amount of Cu and soluble phenols in both shoots and roots. Sulphur-containing amino acids were stimulated in Cu-exposed shoots independently on ploidy level. Potassium content was more reduced in the diploid cultivar. Our data indicate that induction of phenolic metabolism is faster in diploid cultivar which also contained higher amount of Cu. In this view, polyploidisation is a good tool for the reduction of shoot metal accumulation and growth tolerance to Cu excess. Identity of Czech tetraploid cultivar ??Unknown?? is also discussed. 相似文献
45.
The field efficacy of eprinomectin against a natural infection with Muellerius capillaris was evaluated in adult dairy goats. A total of 13 animals were included in a crossover treatment study. Animals were treated with eprinomectin (0.5 mg/kg) in the spring and again in the autumn of 2006, and monitored by enumeration of the lungworm larvae per gram of faeces (LPG). The reduction in LPG on days 7, 21 and 42 after treatment was used to evaluate the anthelmintic efficacy. Both in the spring and in the autumn a 100% reduction (P<0.01) in LPG was observed on days 21 and 42. These results illustrate that eprinomectin applied as a topical pour-on is a practical alternative to benzimidazole treatment of lungworms in dairy goats. No adverse reactions to the eprinomectin treatment were observed. 相似文献
46.
Åke Iverfeldt John Munthe Cyrill Brosset Jozef Pacyna 《Water, air, and soil pollution》1995,80(1-4):227-233
Samples for measurements of total gaseous mercury (Hg) in air have been collected since 1980 in south-western part of Scandinavia. A collection program for precipitation samples used to determine changes in depositional fluxes of total Hg has been in operation since 1987. A comparison of today's total gaseous Hg levels in air and the total Hg concentrations in precipitation with the ones found earlier, shows a clear decrease with time. At the Swedish west-coast, yearly average air concentrations and median levels of 3.3 and 3.1 (1980–1984), 3.2 and 2.8 (1985–1989), and 2.7 and 2.6 ng Hg/m3 (1990–1992), respectively, were found. Increased average and median winter concentrations were always found, with levels at 3.7 and 3.4, 3.7 and 3.3, and 3.0 and 2.7 ng Hg/m3 for the respective time period. Higher winter values were expected due to increased anthropogenic emissions and changes in the mixing height of the atmosphere. The corresponding total wet deposition rates decreased from 27 (1987–1989) to 10 μg Hg/m2 yr. (1990–1992). A finding of special interest was the decreased number of episodic events of high total gaseous Hg levels in air, from 1990 and further on. In addition, the frequency distribution of the concentrations of Hg in air seems to be different for these years compared to the other two time periods. A frequency distribution of air concentrations of Hg more resembling a normal distribution was found for the years 1990 to 1992. The decrease of the atmospheric burden of total gaseous Hg and deposition of total Hg are most probably connected to lower emissions in source areas on the European continent. It seems logical to state that the problem of high Hg depositional fluxes to Scandinavia, is best solved by abatement strategies on the regional scale. 相似文献
47.
Analysis of cell hyperplasia and parietal cell dysfunction induced by Ostertagia ostertagi infection
48.
Jolanta Klukowska‐Rötzler Ludovic Chervet Eliane J. Müller Petra Roosje Eliane Marti Jozef Janda 《Veterinary dermatology》2013,24(1):54-e14
Background – In humans, thymic stromal lymphopoietin (TSLP) plays a central role in the development of allergic inflammation, such as atopic dermatitis (AD), but it is unknown whether it is involved in the pathogenesis of canine AD (CAD). Hypothesis/Objectives – Our aim was to characterize canine TSLP and to assess its expression in CAD. Methods – Canine TSLP was identified based on sequence homology with human TSLP and the complementary DNA (cDNA) cloned by RT‐PCR. Real‐time quantitative RT‐PCR was established to assess the expression of canine TSLP in cultured canine keratinocytes and in skin biopsy specimens from lesional and nonlesional skin of 12 dogs with CAD and eight healthy control dogs. Results – Partial canine TSLP cDNA was cloned and characterized. It contained four exons that shared 70 and 73% nucleotide identity with human and equine TSLP, respectively, encoding the signal peptide and full‐length secreted protein. We found significantly increased TSLP expression in lesional and nonlesional skin of dogs with CAD compared with healthy control dogs (P < 0.05), whereas no difference was measured between lesional and nonlesional samples. In cultured primary canine keratinocytes, we found increased TSLP expression after stimulation with house dust mite allergen extract or Toll‐like receptor ligands lipopolysaccharide and poly I:C. Conclusions and clinical importance – Increased TSLP expression in the skin of dogs with CAD supports an involvement of TSLP in the pathogenesis of CAD similar to that in humans. Further studies should elucidate the function and therapeutic potential of TSLP in CAD. 相似文献
49.
Kyrre Sundseth Jozef M. Pacyna Elisabeth G. Pacyna Damian Panasiuk 《Water, air, and soil pollution》2012,223(1):429-442
Knowledge concerning the main flows of priority substances (PSs) and the production systems and consumption structures in
the society causing these flows is a prerequisite for any attempt to predict and understand their environmental fate as well
as to efficiently minimize future environmental burdens. In this paper, a simple SFA diagram on mercury, including the main
European Union (EU-27) source categories, flows and environmental endpoints which in turn affect the mercury concentrations
in the EU-27 waters are illustrated. From trend analysis and future projections, it becomes obvious that emissions of mercury
as a trace contaminant in fuels and minerals (primary anthropogenic emission sources) are becoming increasingly important
to the environmental concentrations compared to emissions from mercury used intentionally (secondary anthropogenic sources).
Additional future control strategies should therefore be targeted industrial sources and safe treatment of mercury-containing
wastes, wastewater effluents, as well as residues collected from various combustion processes. It was found that knowledge
on flows and emission sources on a large geographical scale is limited due to a lack of information on emission factors from
various industrial processes and waste systems, especially for the mercury being discharges to water and land. 相似文献
50.
Land degradation is not uniform, even in the same landscape, but nevertheless an overall consensus seems to grow on the fact that many areas are under way of rehabilitation. It is a debateable question whether the improving areas are improving because of interventions—or whether this has more to do with processes of innovation and adaptation. The international symposium ‘HighLand2006’ on land degradation and land rehabilitation, held in Mekelle (Ethiopia), from 21 to 25 September 2006, created a forum for those conducting research in East African Highlands as well as in similar regions around the globe to discuss findings. Tropical highlands (>1000 m a.s.l.) cover 4.5 million km2 with an average population density of 33 inhabitants km−2. Nearly all tropical highlands suffer from land degradation, especially medium to very high water erosion. Exchange of experiences during in-door sessions and excursions led to results which are condensed in this special issue. Studies presented tend to invalidate hypotheses on irreversibility of land degradation in tropical mountain areas. Circumstances are that in highly degraded environments, with high pressure on the land, no other alternatives are left open but to improve land husbandry; and that this is particularly successful in places where decision making processes at different levels in society give the highest priority to the implementation of soil and water conservation and other land rehabilitation, in situ and at catchment level. 相似文献