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Metal mixtures in pregnant women and umbilical cord blood at urban populations—Rio de Janeiro,Brazil
de Figueiredo Nataly Damasceno Araújo Monica Seefelder Luiz Ronir R de Magalhaes Câmara Volney do Couto Jacob Silvana dos Santos Lisia Maria Gobbo Vicentini Santos Alves Asmus Carmen Ildes Rodrigues Froes 《Environmental science and pollution research international》2020,27(32):40210-40218
Environmental Science and Pollution Research - This study aims to assess interrelationships between serum lead (Pb), cadmium (Cd), arsenic (As), and mercury (Hg) concentrations in pregnant women in... 相似文献
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A number of different approaches have been used to explain the successes and failures of biodiversity conservation strategies in developing countries. However, to date, little attention has been paid toward assessing the influence of knowledge transfer between science, policy, and conservation practices in the implementation of these strategies. Vietnam’s Pu Luong Cuc Phuong Conservation Area is a globally important ecosystem, situated within a limestone landscape and inhabited by hundreds of local communities. Biodiversity conservation has become an important part of sustainable development in this area. This study analyzes three conservation strategies employed in the Pu Luong Cuc Phuong Conservation Area by applying the Research–Integration–Utilization (RIU) model of scientific knowledge transfer. Our analyses reveal weaknesses in scientific knowledge transfer arising from low-quality research and poor integration strategies. Based on our results, we developed recommendations to improve research and integration in an effort to enhance science-based policy support. 相似文献
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Marcionília Fernandes Pimentel Évila Pinheiro Damasceno Paula Christine Jimenez Pedro Filipe Ribeiro Araújo Marcielly Freitas Bezerra Pollyana Cristina Vasconcelos de Morais Rivelino Martins Cavalcante Susana Loureiro Letícia Veras Costa Lotufo 《Environmental monitoring and assessment》2016,188(5):298
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Susanna López-Legentil Nataly Bontemps-Subielos Xavier Turon Bernard Banaigs 《Marine Biology》2007,151(1):293-299
Temporal variation is one of the least known components of defence production in marine organisms. Here we examined whether
there is a predictable temporal pattern in the production of chemical and structural defences by a marine invertebrate. To
assess the seasonal variation in chemical defence, we measured ascididemin, the main pyridoacridine alkaloid in the blue Mediterranean
morph of the ascidian Cystodytes sp. Structural defence variability was assessed on the basis of colony ash content, as it contains mainly spicules. Ascididemin
concentration and the colony ash content displayed an annual cycle, reaching a minimum in spring and peaking in summer. Cross-correlation
analyses with existing data on growth and reproduction suggested a significant trade-off between investment in reproduction
and the other biological parameters considered (growth, inorganic content and ascididemin concentration). Our results suggest
that optimization of resource allocation, probably influenced by biotic interactions and physical factors, shaped the temporal
trends observed in secondary metabolite concentration and inorganic content. 相似文献
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D. J. McRae S. G. Conard G. A. Ivanova A. I. Sukhinin S. P. Baker Y. N. Samsonov T. W. Blake V. A. Ivanov A. V. Ivanov T. V. Churkina W. M. Hao K. P. Koutzenogij Nataly Kovaleva 《Mitigation and Adaptation Strategies for Global Change》2006,11(1):45-74
As part of the Russian FIRE BEAR (Fire Effects in the Boreal Eurasia Region) Project, replicated 4-ha experimental fires were
conducted on a dry Scotch pine (Pinus sylvestris)/lichen (Cladonia sp.)/feathermoss (Pleurozeum schreberi) forest site in
central Siberia. Observations from the initial seven surface fires (2000-2001) ignited under a range of burning conditions
quantified the different fuel consumption and fire behavior characteristics (e.g., rate of spread, fireline intensity, etc.)
possible in this particular forest fuel type. Experimental results and dendrochronological study of local fire history both
support the dominance of local fire regimes by low to moderate-intensity surface fires. Carbon released by the experimental
fires ranged from 4.8 to 15.4 t C ha− 1 depending on fuel conditions and fire severity. Preliminary emission data show a strong correlation between carbon dioxide
(CO2) and carbon monoxide (CO) emissions, which should facilitate accurate estimates of fire impacts on atmospheric chemistry.
Carbon concentration in smoke samples was related to fire severity. The short landscape-scale fire-return interval (50 years),
combined with typically low fire severity, in pine ecosystems of central Siberia is often associated with low tree mortality
and relatively rapid buildup of litter and understory fuels after a fire. 相似文献
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Damasceno LH Rodrigues JA Ratusznei SM Zaiat M Foresti E 《Journal of environmental management》2007,85(4):927-935
An investigation was carried out on the performance of an anaerobic sequencing batch biofilm reactor (ASBBR) treating diluted cheese whey when submitted to different feed strategies and volumetric organic loads (VOL). Polyurethane foam cubes were used as support for biomass immobilization and stirring was provided by helix impellers. The reactor with a working volume of 3 L treated 2 L of wastewater in 8-h cycles at 500 rpm and 30 degrees C. The organic loads applied were 2, 4, 8 and 12 g COD L(-1) d(-1), obtained by increasing the feed concentration. Alkalinity was supplemented at a ratio of 50% NaHCO(3)/COD. For each organic load applied three feed strategies were tested: (a) batch operation with 8-h cycle; (b) 2-h fed-batch operation followed by 6-h batch; and (c) 4-h fed-batch followed by 4-h batch. The 2-h fed-batch operation followed by 6-h batch presented the best results for the organic loads of 2 and 4 g COD L(-1) d(-1), whereas the 4-h fed-batch operation followed by 4-h batch presented results slightly inferior for the same organic loads and the best results at organic loads of 8 and 12 g COD L(-1) d(-1). The concentration of total volatile acids varied with fill time. For the higher fill times maximum concentrations were obtained at the end of the cycle. Moreover, no significant difference was detected in the maximum concentration of total volatile acids for any of the investigated conditions. However, the maximum values of propionic acid tended to decrease with increasing fill time considering the same organic load. Microbiological analyses revealed the presence of Methanosaeta-like structures and methanogenic hydrogenotrophic-like fluorescent bacilli. No Methanosarcina-like structures were observed in the samples. 相似文献
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