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31.
Sigr��n H. J��nasd��ttir J?rg Dutz Marja Koski Lidia Yebra Hans Henrik Jakobsen Charles Vidoudez Georg Pohnert Jens C. Nejstgaard 《Marine Biology》2011,158(9):1943-1963
Egg and faecal pellet production and egg hatching success of the calanoid copepod Calanus finmarchicus were monitored over a period of 14?days (14?C28 April, 2008) while fed water from 4 differently treated mesocosms and ambient water. Two of the mesocosms used were inoculated with the polyunsaturated aldehyde (PUA)-producing diatom Skeletonema marinoi, while 2 received only nutrient additions with or without silica. The mesocosms developed blooms of S. marinoi, mixed diatoms or the haptophyte Phaeocystis pouchetii, respectively. Faecal pellet production of C. finmarchicus increased with increasing food availability. Egg production increased with time in all mesocosms to a maximum single female production of 232 eggs female?1?day?1 (average of 90 eggs female?1?day?1) and followed the development of ciliates and P. pouchetii, but was not affected by the observed high (up to 15?nmol?L?1) PUA production potential of the phytoplankton. The hatching success of the eggs produced on the mesocosm diets was high (78?C96%) and was not affected by either aldehydes in the maternal diet or exposure to the dissolved aldehydes in the water. 相似文献
32.
Sarma SS Osnaya-Espinosa LR Aguilar-Acosta CR Nandini S 《Journal of environmental biology / Academy of Environmental Biology, India》2011,32(4):473-480
This studywas undertaken to quantify the seasonal variations of zooplankton (rotifers, cladocerans and copepods) and selected physico-chemical variables (temperature, pH, conductivity, Secchi disc transparency, dissolved oxygen, ammonia, nitrate and phosphate concentrations) in the Iturbide dam. Monthly zooplankton samples (50 l filtered through 50 microm mesh, in duplicates from each of the 4 stations) were collected from February 2008 to January 2009. Simultaneously physico-chemical variables were measured. The zooplankton samples were fixed in 4% formalin in the field. In general, the temperature ranged from 9 to 16 degrees C, rarely exceeding 20 degrees C. Secchi transparency was nearly 100% since the reservoir was shallow (< 2 m) even during the rainy seasons. Dissolved oxygen was generally high, 13-18 mg l(-1). Nitrate levels (10 to 170 microg l(-1)) were low while phosphates were relatively high (9 to 35 microg l(-1)). The Iturbide reservoir was dominated by rotifer species. We encountered in all, 55 taxa of rotifers, 9 cladocerans and 2 copepods. The rotifer families Trichocercidae and Notommatidae had the highest number of species (7 each) followed by Colurellidae and Lecanidae (6 and 5 species, respectively). Trichocerca elongata, Ascomorpha ovalis, K. americana, K. cochlearis, Lepadella patella and Pompholyx sulcata were the dominant rotifers during the study period. On an annual average, rotifer density ranged between 50-200 ind.(-1). Among crustaceans Chydorus brevilabris and Macrothrix triserialis were most abundant. The maximal density of these cladocerans was about 50 ind. l(-1). Copepods were much lower in numbers (< 20 ind. l(-1)). In general the density of zooplankton was higher during summer months (April to July) than during winter. Shannon-Wiener diversity index varied from 1.0 to 4.3 depending on the site and the sampling period. Based on the data of Secchi transparency and nutrient concentrations, the Iturbide reservoir appeared to be mesotrophic. 相似文献
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34.
René E. van Dijk Lidia A. Mészáros Marco van der Velde Tamás Székely Ákos Pogány János Szabad Jan Komdeur 《Behavioral ecology and sociobiology》2010,64(9):1425-1435
Engagement in extra-pair copulations is an example of the abundant conflicting interests between males and females over reproduction.
Potential benefits for females and the risk of cuckoldry for males are expected to have important implications on the evolution
of parental care. However, whether parents adjust parental care in response to parentage remains unclear. In Eurasian penduline
tits Remiz pendulinus, which are small polygamous songbirds, parental care is carried out either by the male or by the female. In addition, one
third of clutches is deserted by both male and female. Desertion takes place during the egg-laying phase. Using genotypes
of nine microsatellite loci of 443 offspring and 211 adults, we test whether extra-pair paternity predicts parental care.
We expect males to be more likely to desert cuckolded broods, whereas we expect females, if they obtain benefits from having
multiple sires, to be more likely to care for broods with multiple paternity. Our results suggest that parental care is not
adjusted to parentage on an ecological timescale. Furthermore, we found that male attractiveness does not predict cuckoldry,
and we found no evidence for indirect benefits for females (i.e., increased growth rates or heterozygosity of extra-pair offspring).
We argue that male Eurasian penduline tits may not be able to assess the risk of cuckoldry; thus, a direct association with
parental care is unlikely to evolve. However, timing of desertion (i.e., when to desert during the egg-laying phase) may be
influenced by the risk of cuckoldry. Future work applying extensive gene sequencing and quantitative genetics is likely to
further our understanding of how selection may influence the association between parentage and parental care. 相似文献
35.
Life cycle assessment of biogas upgrading technologies 总被引:1,自引:0,他引:1
Starr K Gabarrell X Villalba G Talens L Lombardi L 《Waste management (New York, N.Y.)》2012,32(5):991-999
This article evaluates the life cycle assessment (LCA) of three biogas upgrading technologies. An in-depth study and evaluation was conducted on high pressure water scrubbing (HPWS), as well as alkaline with regeneration (AwR) and bottom ash upgrading (BABIU), which additionally offer carbon storage. AwR and BABIU are two novel technologies that utilize waste from municipal solid waste incinerators - namely bottom ash (BA) and air pollution control residues (APC) - and are able to store CO(2) from biogas through accelerated carbonation processes. These are compared to high pressure water scrubbing (HPWS) which is a widely used technology in Europe. The AwR uses an alkaline solution to remove the CO(2) and then the solution - rich in carbonate and bicarbonate ions - is regenerated through carbonation of APC. The BABIU process directly exposes the gas to the BA to remove and immediately store the CO(2), again by carbonation. It was determined that the AwR process had an 84% higher impact in all LCA categories largely due to the energy intensive production of the alkaline reactants. The BABIU process had the lowest impact in most categories even when compared to five other CO(2) capture technologies on the market. AwR and BABIU have a particularly low impact in the global warming potential category as a result of the immediate storage of the CO(2). For AwR, it was determined that using NaOH instead of KOH improves its environmental performance by 34%. For the BABIU process the use of renewable energies would improve its impact since accounts for 55% of the impact. 相似文献
36.
Lidia Zapór 《International journal of occupational safety and ergonomics》2004,10(4):319-331
Cytotoxicity of 5 phenol derivatives (phenol, catechol, resorcinol, hydroquinone and phloroglucinol) was tested using a mouse 3T3 fibroblast cell line. Its relationships with structural and physicochemical properties were investigated. Linear regression analysis and Pearson's correlation coefficient were used to characterise the relationship between cytotoxicity (expressed by IC(50) values) and physicochemical parameters of compounds or their toxicity in vivo expressed by LD(50) values. The studies showed that physicochemical properties of compounds seemed to have less influence on their cytotoxic potency than structural properties. Cytotoxicity of the compounds probably depends on the number of -OH groups and their location in the aromatic ring more than on physicochemical properties of compounds. The best correlation was obtained for IC(50) values and LD(50) values determined following rabbit skin administration and experimental skin irritation score. 相似文献
37.
Kudłak B Rogowska J Wolska L Kałas M Łęczyński L Namieśnik J 《Journal of environmental monitoring : JEM》2012,14(4):1231-1236
The paper presents the results of toxicity determinations carried out on sediment samples collected in the vicinity of the wreck of the German s/s Stuttgart (the southern part of the Gulf of Gdańsk, off the Polish coast) in relation to the determination of polycyclic aromatic hydrocarbons (PAHs). The toxicity of surface and core sediment samples was assessed using two biotest organisms-the bioluminescent bacteria Vibrio fischeri and the ostracod Heterocypris incongruens. PAH levels in these samples were determined by GC-MS. The surface sediments collected at W2 (ca. 34 m north of the shipwreck) and W4 (ca. 415 m north-east of the wreck) as well as the core sediments collected at WR3 (ca. 400 m north-east of the wreck) were the most heavily polluted with substances toxic to the biotest organisms. The chronic and acute toxicities in the case of most of the surface sediment samples studied are correlated. This may suggest that not only hydrophobic chemicals (like PAHs from fuel residues) but also more polar chemicals (resulting from the conversion of aromatic hydrocarbons) are responsible for the toxicity levels found. There is a clear dependence between the levels of chronic toxicity and PAH concentrations in the core sediment samples. In addition, a simultaneous decrease in the PAH content and chronic toxicity was noted in all the core sediment samples at depths below 80 cm. 相似文献
38.
Friend AJ Ayoko GA Jayaratne ER Jamriska M Hopke PK Morawska L 《Environmental science and pollution research international》2011,19(7):2942-2950
Purpose
To investigate the significance of sources around measurement sites, assist the development of control strategies for the important sources and mitigate the adverse effects of air pollution due to particle size.Methods
In this study, sampling was conducted at two sites located in urban/industrial and residential areas situated at roadsides along the Brisbane Urban Corridor. Ultrafine and fine particle measurements obtained at the two sites in June?CJuly 2002 were analysed by positive matrix factorization.Results
Six sources were present, including local traffic, two traffic sources, biomass burning and two currently unidentified sources. Secondary particles had a significant impact at site 1, while nitrates, peak traffic hours and main roads located close to the source also affected the results for both sites.Conclusions
This significant traffic corridor exemplifies the type of sources present in heavily trafficked locations and future attempts to control pollution in this type of environment could focus on the sources that were identified. 相似文献39.
Hussein Kanaani Megan Hargreaves Zoran Ristovski Lidia Morawska 《Atmospheric environment (Oxford, England : 1994)》2009,43(24):3725-3735
The aim of this study was to characterise and quantify the fungal fragment propagules derived and released from several fungal species (Penicillium, Aspergillus niger and Cladosporium cladosporioides) using different generation methods and different air velocities over the colonies. Real time fungal spore fragmentation was investigated using an Ultraviolet Aerodynamic Particle Sizer (UVASP) and a Scanning Mobility Particle Sizer (SMPS). The study showed that there were significant differences (p < 0.01) in the fragmentation percentage between different air velocities for the three generation methods, namely the direct, the fan and the fungal spore source strength tester (FSSST) methods. The percentage of fragmentation also proved to be dependent on fungal species. The study found that there was no fragmentation for any of the fungal species at an air velocity ≤0.4 m s?1 for any method of generation. Fluorescent signals, as well as mathematical determination also showed that the fungal fragments were derived from spores. Correlation analysis showed that the number of released fragments measured by the UVAPS under controlled conditions can be predicted on the basis of the number of spores, for Penicillium and A. niger, but not for C. cladosporioides. The fluorescence percentage of fragment samples was found to be significantly different to that of non-fragment samples (p < 0.0001) and the fragment sample fluorescence was always less than that of the non-fragment samples. Size distribution and concentration of fungal fragment particles were investigated qualitatively and quantitatively, by both UVAPS and SMPS, and it was found that the UVAPS was more sensitive than the SMPS for measuring small sample concentrations, whilethe results obtained from the UVAPS and SMAS were not identical for the same samples. 相似文献
40.
G. Buonanno L. Morawska L. Stabile A. Viola 《Atmospheric environment (Oxford, England : 1994)》2010,44(32):3963-3969
The aim of this work was to quantify exposure to particles emitted by wood-fired ovens in pizzerias. Overall, 15 microenvironments were chosen and analyzed in a 14-month experimental campaign. Particle number concentration and distribution were measured simultaneously using a Condensation Particle Counter (CPC), a Scanning Mobility Particle Sizer (SMPS), an Aerodynamic Particle Sizer (APS). The surface area and mass distributions and concentrations, as well as the estimation of lung deposition surface area and PM1 were evaluated using the SMPS-APS system with dosimetric models, by taking into account the presence of aggregates on the basis of the Idealized Aggregate (IA) theory. The fraction of inhaled particles deposited in the respiratory system and different fractions of particulate matter were also measured by means of a Nanoparticle Surface Area Monitor (NSAM) and a photometer (DustTrak DRX), respectively. In this way, supplementary data were obtained during the monitoring of trends inside the pizzerias. We found that surface area and PM1 particle concentrations in pizzerias can be very high, especially when compared to other critical microenvironments, such as the transport hubs. During pizza cooking under normal ventilation conditions, concentrations were found up to 74, 70 and 23 times higher than background levels for number, surface area and PM1, respectively. A key parameter is the oven shape factor, defined as the ratio between the size of the face opening in respect to the diameter of the semicircular oven door, and particular attention must also be paid to hood efficiency. 相似文献