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991.
Leclaire S White J Arnoux E Faivre B Vetter N Hatch SA Danchin E 《Die Naturwissenschaften》2011,98(9):773-782
Carotenoid pigments are important for immunity and as antioxidants, and carotenoid-based colors are believed to provide honest
signals of individual quality. Other colorless but more efficient antioxidants such as vitamins A and E may protect carotenoids
from bleaching. Carotenoid-based colors have thus recently been suggested to reflect the concentration of such colorless antioxidants,
but this has rarely been tested. Furthermore, although evidence is accruing for multiple genetic criteria for mate choice,
carotenoid-based colors have rarely been shown to reflect both phenotypic and genetic quality. In this study, we investigated
whether gape, tongue, eye-ring, and bill coloration of chick-rearing black-legged kittiwakes Rissa tridactyla reflected circulating levels of carotenoids and vitamins A and E. We further investigated whether integument coloration reflected
phenotypic (body condition and fledging success) and genetic quality (heterozygosity). We found that the coloration of fleshy
integuments was correlated with carotenoid and vitamin A levels and fledging success but only in males. Furthermore, the coloration
of tongue and eye-ring was correlated with heterozygosity in both males and females. Integument colors might therefore be
reliable signals of individual quality used by birds to adjust their parental care during the chick-rearing period. 相似文献
992.
The interaction between emissions trading and renewable electricity support schemes. An overview of the literature 总被引:1,自引:0,他引:1
Pablo del Río González 《Mitigation and Adaptation Strategies for Global Change》2007,12(8):1363-1390
The public promotion of electricity from renewable energy sources coexists in many countries with the recent implementation
of emissions trading schemes. As shown by several papers, this coexistence may lead to significant interactions between both
instruments, in the form of synergies and conflicts. This paper provides an overview and analysis of the literature on such
coexistence and interactions. A major conclusion is that policy measures aiming at exploiting the synergies between both instruments
should be implemented. The greatest synergy effects from the use of both instruments take place through appropriate coordination
of their targets. Another key finding is that, although some stylised facts can be inferred from the studies, some results
from those complex interactions are context-specific since they depend on the design of the instruments in particular countries.
In spite of the significant policy implications of such interactions for the effective and cost-effective functioning of both
instruments, this is a surprisingly under searched field. It is so concerning, both, theoretical and empirical analysis.
相似文献
Pablo del Río GonzálezEmail: |
993.
Radionuclides from past uranium mining in rivers of Portugal 总被引:2,自引:0,他引:2
Carvalho FP Oliveira JM Lopes I Batista A 《Journal of environmental radioactivity》2007,98(3):298-314
During several decades and until a few years ago, uranium mines were exploited in the Centre of Portugal and wastewaters from uranium ore milling facilities were discharged into river basins. To investigate enhancement of radioactivity in freshwater ecosystems, radionuclides of uranium and thorium series were measured in water, sediments, suspended matter, and fish samples from the rivers Vouga, D?o, Távora and Mondego. The results show that these rivers carry sediments with relatively high naturally occurring radioactivity, and display relatively high concentrations of radon dissolved in water, which is typical of a uranium rich region. Riverbed sediments show enhanced concentrations of radionuclides in the mid-section of the Mondego River, a sign of past wastewater discharges from mining and milling works at Urgeiri?a confirmed by the enhanced values of (238)U/(232)Th radionuclide ratios in sediments. Radionuclide concentrations in water, suspended matter and freshwater fish from that section of Mondego are also enhanced in comparison with concentrations measured in other rivers. Based on current radionuclide concentrations in fish, regular consumption of freshwater species by local populations would add 0.032 mSv a(-1) of dose equivalent (1%) to the average background radiation dose. Therefore, it is concluded that current levels of enhanced radioactivity do not pose a significant radiological risk either to aquatic fauna or to freshwater fish consumers. 相似文献
994.
995.
The catalytic activity of Pd catalysts supported on Ce0.73Tb0.27Ox/SiO2, Ce0.6Zr0.4Ox/SiO2, Ce0.73Tb0.27Ox/La2O3-Al2O3 and Ce0.6Zr0.4Ox/La2O3-Al2O3 was studied using the reduction of NO by CO. The catalysts were characterized by X-ray fluorescence, surface area, X-ray diffraction, temperature-programmed reduction, CO chemisorption and oxygen storage capacity. Temperature-programmed reduction results indicated that Tb or Zr incorporation improves the reducibility and oxygen storage capacity. CO chemisorption data suggested the presence of large PdO particles due to the low CO/Pd ratio. No significant differences were obtained in light off temperatures (TLight off) for all Pd catalysts and the most active was 1.5%Pd/Ce0.6Zr0.4Ox/SiO2. 相似文献
996.
Hong Guo Kwanho Jeong Jiyeon Lim Jeongwon Jo Young Mo Kim Jong-pyo Park Joon Ha Kim Kyung Hwa Cho 《环境科学学报(英文版)》2015
Of growing amount of food waste, the integrated food waste and waste water treatment was regarded as one of the efficient modeling method. However, the load of food waste to the conventional waste treatment process might lead to the high concentration of total nitrogen (T-N) impact on the effluent water quality. The objective of this study is to establish two machine learning models—artificial neural networks (ANNs) and support vector machines (SVMs), in order to predict 1-day interval T-N concentration of effluent from a wastewater treatment plant in Ulsan, Korea. Daily water quality data and meteorological data were used and the performance of both models was evaluated in terms of the coefficient of determination (R2), Nash–Sutcliff efficiency (NSE), relative efficiency criteria (drel). Additionally, Latin-Hypercube one-factor-at-a-time (LH-OAT) and a pattern search algorithm were applied to sensitivity analysis and model parameter optimization, respectively. Results showed that both models could be effectively applied to the 1-day interval prediction of T-N concentration of effluent. SVM model showed a higher prediction accuracy in the training stage and similar result in the validation stage. However, the sensitivity analysis demonstrated that the ANN model was a superior model for 1-day interval T-N concentration prediction in terms of the cause-and-effect relationship between T-N concentration and modeling input values to integrated food waste and waste water treatment. This study suggested the efficient and robust nonlinear time-series modeling method for an early prediction of the water quality of integrated food waste and waste water treatment process. 相似文献
997.
Lucie Flache Sezin Czarnecki Rolf-Alexander Dring Uwe Kierdorf Jorge A. Encarnao 《环境科学学报(英文版)》2015,27(5):184-193
Metal-contaminated soils and sediments are widespread in urbanized areas due to atmospheric deposition close to emission sources. These metals are bio-available for organisms, e.g., insects, and accumulate in food chains of insectivorous mammals. Especially bats, which live in urban regions and ingest large amounts of food relative to their body mass, are at risk of being poisoned due to the accumulation of trace metals. To determine species-specific trace metal contents in bats from urban environments, hair samples were analyzed by ICP-OES. Observed trace metal concentrations were related to species-specific foraging habitat, prey spectrum and degree of synanthropy. The species studied were Pipistrellus pipistrellus, Myotis daubentonii and Nyctalus noctula. P. pipistrellus showed the highest concentrations of lead and zinc and slightly higher concentrations of cadmium than the other two species, which was related to its high degree of synanthropy with foraging habitat mostly located in cities. In contrast, N. noctula displayed the highest contents of manganese and copper. The reason might be found in its prey spectrum, as N. noctula feeds mainly on beetles that are caught in cultured areas. Trace metal concentrations determined in hair samples of M. daubentonii ranged between the values of P. pipistrellus and N. noctula, probably reflecting an intermediate level of synanthropy. Positive correlations were observed between the concentrations of cadmium and lead and those of manganese and copper. Hair samples from bats are suitable monitoring tools to study trace metal exposure and can be used to determine differences in trace metal levels between species. 相似文献
998.
Maria Helena Guimarães Annie McKee Maria Luísa Lima Lia Vasconcelos Tomasz Boski Tomaz Dentinho 《Journal of Environmental Planning and Management》2015,58(10):1827-1852
The definition of management actions in natural resource management requires the integration of all types of knowledge involved. An appropriate approach for such a challenge is the ideal of transdisciplinarity. A transdisciplinary process can be considered “consultative” when knowledge is simply gathered and collated, or “participatory” when knowledge integration is undertaken collectively. In this paper, we present a mixed mode procedure (i.e., using interviews, questionnaires, and group discussions) that empirically demonstrates the difference between consultative and participatory transdisciplinary processes. The mixed mode procedure is used for identifying the most relevant problems occurring in the coastal system of Praia da Vitória bay, Azores, Portugal. This mixed mode procedure is likely to be useful for other studies, because the results highlight the need to promote face-to-face interaction at the earliest opportunity, and because it allows an understanding to be gained of social learning processes, the influence of power, and participant behaviour during interaction with others. 相似文献
999.
Angéline?BertinEmail author Victor?H.?Ruíz Ricardo?Figueroa Nicolas?Gouin 《Die Naturwissenschaften》2012,99(3):225-232
Wildlife data often show spatial organization, demonstrating positive correlations either as a result of processes occurring
over the landscape or due to the influence of spatially structured environmental variables. It is, thus, essential to consider
non-random spatial structure when evaluating the underlying causes of biological variation. In this study, we analyzed the
population structure of Chilina dombeyana shell morphology of 14 populations that are close geographically and belong to the same hydrographic basin. We utilized a
variation partitioning approach to evaluate the importance of spatial processes, such as migration, acting over the landscape,
and environmental characteristics, including habitat and hydrologic characteristics, and the occurrence of aquatic predators
in promoting between population variation. Our results demonstrate spatially structured variation in C. dombeyana shell morphology, with populations living near each other having more similar shell sizes than populations living farther
apart. The shell size variation partition indicated that both spatially structured environmental factors and genetic relationships
resulting from migration or shared common ancestry may explain this pattern. Shell shape variation, in contrast, was found
to be essentially under the influence of non-spatially structured environmental factors, with habitat and water characteristics
accounting for about half of the total variation among populations. The large proportion of the variation in shell size that
is spatially structured demonstrates that spatial structure on morphological traits might be strong and highlights the need
to consider such phenomenon in intraspecific studies of phenotypic evolution. 相似文献
1000.
Fonseca-Bermúdez Óscar Javier Giraldo Liliana Sierra-Ramírez Rocío Moreno-Piraján Juan Carlos 《Environmental Chemistry Letters》2023,21(2):1059-1073
Environmental Chemistry Letters - Biogas is a renewable fuel produced from modern biomass, yet biogas contains traces of hydrogen sulfide, a toxic compound, that must be removed before biogas... 相似文献