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81.
Rui Rosa Marta S. Pimentel Miguel Baptista Katja Trübenbach Ricardo Calado Maria L. Nunes Ana Moreno João Pereira 《Marine Biology》2013,160(2):263-275
The present study provides a comprehensive analysis of the biochemical composition (proximate composition, amino acids and fatty acids in gonad, digestive gland and muscle) of the cirrate octopod, Opisthoteuthis calypso, collected off the coast of Portugal. Protein and energy contents of O. calypso were significantly lower (p < 0.05) than those observed for coastal octopods, suggesting that the gelatinous musculature of the cirrate octopus may not be a direct consequence of food limitation, but rather associated with reduced selective pressure for strong swimming ability in the deep sea. Moreover, principal component analyses of fatty acid (FA) data clearly separated coastal octopods from O. calypso. Saturated FA biomarkers (namely 16:0, 17:0, 18:0) and monounsaturated FA 22:1 suggest a higher phytodetrital influence on diet of O. calypso. A clear separation between groups was also observed with amino acid (AA) data. However, essential AA and non-essential AA designations (based on the flow of carbon through biochemical systems) do not necessarily provide an accurate picture of the origins of amino nitrogen in the deep-sea environment. Consequently, the interpretation of the present data is a challenging task but opens a new window of opportunity to unravel new trophic biomarkers in the deep sea. 相似文献
82.
A Baumann DL Holness P Norman D Idriss-Wheeler P Boucher 《Journal of Safety Research》2012,43(3):205-213
IntroductionThis article presents a health and safety intervention model and the use of process evaluation to assess a participatory ergonomic intervention.MethodThe effectiveness of the Ergonomic Program Implementation Continuum (EPIC) was assessed at six healthcare pilot sites in Ontario, Canada. The model provided a framework to demonstrate evaluation findings.ResultsParticipants reported that EPIC was thorough and identified improvements related to its use. Participants believed the program contributed to advancing an organizational culture of safety (COS). Main barriers to program uptake included resistance to change and need for adequate funding and resources. The dedication of organizational leaders and consultant coaches was identified as essential to the program's success.Impact on IndustryIn terms of impact on industry, findings contribute to the evidence-based knowledge of health and safety interventions and support use of the framework for creating a robust infrastructure to advance organizational COS and link staff safety and wellness with patient safety in healthcare. 相似文献
83.
Flow and diffusion of water in natural porous media, quartz sand, and calcareous gravel were measured using a 1.5-T clinical magnetic resonance tomograph. The spatial resolution of the dynamic measurements was 1.32 x 1.32 x 5 mm3, and the time between two cross-sectional measurements was approximately 10 s. The measured coefficients of molecular diffusion for water were in good agreement with theoretical data. Flow was measured without any tracer at velocities between 0.15 and 6.67 mm/s. The results, based on a calibration within one part of the column, were in good agreement with data obtained from a tracer experiment and from a numerical model. It was possible to measure the flow velocity in larger pores and preferential flow paths directly. The results of the flow measurements in smaller pores reflected the mean velocity within that volume element. In that case the obtained values were close to the average linear velocity. Since the time resolution is high a monitoring of flow processes is possible. The pore space was imaged with a spatial resolution of 0.5 x 0.5 x 0.5 mm3. Here, the porosity of pores that are larger than 0.2 mm can be measured directly; for smaller pores a calibration is necessary. 相似文献
84.
Zimmermann S Baumann U Taraschewski H Sures B 《Environmental pollution (Barking, Essex : 1987)》2004,127(2):195-202
The platinum group metals (PGM) Pt and Rh are emitted into the environment mainly by catalytic exhaust gas converters of cars and by effluents of hospitals, which use Pt based anti-cancer drugs. However, there is still a lack of information on the availability of these precious metals to the biosphere. As PGM accumulate in sediments of aquatic ecosystems we focused our study on the uptake of the noble metals by European eels, Anguilla anguilla. Therefore, eels were exposed in tap water and humic water containing Pt(4+) and Rh(3+) at a concentration of 170 and 260 microg/l, respectively. After an exposure period of 6 weeks the mean Pt levels in bile, liver, kidney and intestine of the exposed eels ranged between 68 ng/g and 840 ng/g and the mean Rh levels between 35 ng/g and 155 ng/g whereas the PGM levels of the unexposed controls were below the detection limit of 50 ng/g for Pt and 5 ng/g for Rh. Rh was also taken up by gill and spleen. No PGM uptake was found for muscle and blood. The pattern of metal distribution within the eel differed between Pt and Rh and was dependent on the water type. Due to their accumulation capacity for PGM eels are suitable as accumulation indicators to detect PGM pollution in aquatic ecosystems. 相似文献
85.
Gert Van Hoey Katja Guilini Marijn Rabaut Magda Vincx Steven Degraer 《Marine Biology》2008,154(6):1009-1019
The common tube-building polychaete Lanice conchilega is known as a habitat structuring species and can form dense aggregations. The effects of L. conchilega on the surrounding benthic community have received little attention, especially in subtidal areas. Therefore, the presence
of L. conchilega in different habitats in the North Sea and its effect on the abundance, species richness, diversity and community structure
in these habitats are evaluated in the present paper, based on data from the ICES North Sea Benthos Survey of 2000. Lanice conchilega has a wide geographical distribution and a low habitat specialization, but optimally occurs in shallow fine sands. In the
present study, the presence of L. conchilega resulted in a density increase and a significant (positive) correlation of the benthos density with the density of L. conchilega. Furthermore, the species richness (number of species) increased with increasing density of L. conchilega. This trend was, however, not consistent: the number of species reached more or less an asymptotic value or even decreased
after reaching a critical density of L. conchilega (>500–1,000 ind/m2), as observed in shallow fine sands. The same overall pattern was detected concerning the expected number
of species. The N
1-diversity index showed similar or slightly higher values in L. conchilega patches compared to patches without L. conchilega. From the results of the community analysis, it can be concluded that the species, which were responsible for the increase
of the diversity, belonged to the overall species-pool of that habitat. The effects on density and diversity differed between
the four discerned habitats (shallow muddy sand, shallow fine sand, shallow medium sand and deep fine sand), and were most
pronounced in shallow fine sands. These patterns can be attributed to the habitat structuring capacity of L. conchilega. The mechanisms responsible for the increase of the habitat quality in patches of L. conchilega can be summarized as (1) changes in the hydrodynamics, (2) increases of the habitat stability and oxygen supply, and (3)
a creation of habitat heterogeneity in a uniform environment. In this way, L. conchilega alters the habitat characteristics and affects other organisms, and can therefore even be considered as an ecosystem engineer.
In other words, L. conchilega patches are responsible for an increased habitat quality in an otherwise uniform habitat, which results in a higher survival
of the surrounding benthic species. 相似文献
86.
Differential interests between the sexes regarding the number of copulations can result in sexual harassment. Hence, females
may have less time available for foraging. Male sexual harassment often leads to fitness reduction in females. We used the
mating complex of the bisexual fish Poecilia mexicana and the co-occurring all-female Poecilia formosa to study sexual harassment and its incurred cost on female feeding efficiency. P. formosa is a sperm-dependent parthenogen that requires mating with host males to induce embryogenesis, but the male genes are not
used. We therefore predicted P. mexicana males to prefer conspecific females. Hence, costs of male sexual harassment should not occur in unisexuals. While P. formosa are at a disadvantage compared to P. mexicana females due to male mate choice (leading to sperm limitation), this could be traded-off by suffering less from sexual harassment.
In our experiment, we found males to direct significantly more pre-copulatory mating behaviour towards conspecific females,
whereas actual mating attempts did not differ between species. Contrary to our prediction, both types of females started feeding
later and spent less time feeding in the presence of a male partner compared to the time spent feeding with another female,
suggesting that females of both species suffer from male harassment. The focal females' feeding time declined with increasing
body size of the female competitor, and the same pattern was found when a male was present. We discuss that—besides sexual
harassment—other factors such as food competition and female mate choice may affect female feeding efficiency. 相似文献
87.
88.
Important parameters relevant to waters such as bioelimination, mineralisation, toxicity of activated sludge and the inhibition of nitrifiers can be determined in a very short time by means of simple trickling filters. Based on such test results we can assess the behaviour of substances, products and components of waste water in sewage purification plants. The trickling filters enable us to obtain persistent hydrophilic and hydrophobic metabolites which can be used for tests relevant to ecotoxicology. 相似文献
89.
Clément Stahl Vincent Freycon Sébastien Fontaine Camille Dezécache Lise Ponchant Catherine Picon-Cochard Katja Klumpp Jean-François Soussana Vincent Blanfort 《Regional Environmental Change》2016,16(7):2059-2069
Recent studies suggest that carbon (C) is stored in the topsoil of pastures established after deforestation. However, little is known about the long-term capacity of tropical pastures to sequester C in different soil layers after deforestation. Deep soil layers are generally not taken into consideration or are underestimated when C storage is calculated. Here we show that in French Guiana, the C stored in the deep soil layers contributes significantly to C stocks down to a depth of 100 cm and that C is sequestered in recalcitrant soil organic matter in the soil below a depth of 20 cm. The contribution of the 50–100 cm soil layer increased from 22 to 31 % with the age of the pasture. We show that long-term C sequestration in C4 tropical pastures is linked to the development of C3 species (legumes and shrubs), which increase both inputs of N into the ecosystem and the C:N ratio of soil organic matter. The deep soil under old pastures contained more C3 carbon than the native forest. If C sequestration in the deep soil is taken into account, our results suggest that the soil C stock in pastures in Amazonia would be higher with sustainable pasture management, in particular by promoting the development of legumes already in place and by introducing new species. 相似文献
90.
Tanja Myllyviita Katja Lähtinen Teppo Hujala Leena A. Leskinen Lauri Sikanen Pekka Leskinen 《Environment, Development and Sustainability》2014,16(2):287-304
Cultural sustainability has become a much discussed topic in the forestry and bioenergy sectors. However, there are not many indicators available for measuring cultural sustainability. In order to identify indicators for the assessment of the cultural sustainability impacts of wood-based bioenergy in eastern Finland, two-phased expert interviews were conducted. The process was supported by a hybrid approach: A qualitative mapping technique was applied when the indicators were identified, and weights for the indicators were set using a quantitative rating technique. The experts identified 49 indicators of cultural sustainability. Most of the generated indicators were relevant for local uses and highlighted the perceptions of the general public. Furthermore, most of the indicators were relevant from the perspective of raw material acquisition. Applying methods of differing backgrounds enabled advanced problem structuring, which allowed the identification of indicators suitable for assessing cultural sustainability of wood-based bioenergy in Eastern Finland. The quantitative rating technique enabled the determination of the importance of the indicators generated. Nevertheless, it seems that the hybrid approaches have many challenges related to the quantitative measuring of the participants’ perceptions. Cultural sustainability indicators should be identified within a case study, since it seems that most of the cultural sustainability indicators are case specific. The process introduced here offers steps for identifying case-specific cultural sustainability indicators; however, the concept of cultural sustainability cannot be strictly defined. 相似文献