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Cleaves HJ Crapster-Pregont E Jonsson CM Jonsson CL Sverjensky DA Hazen RA 《Chemosphere》2011,83(11):1560-1567
We studied the adsorption of short single-stranded deoxyribonucleic acid (ssDNA) oligomers, of approximately 30 nucleotides (nt) in length, of varying sequence, adenine + guanine + cytosine (AGC) content, and propensity to form secondary structure, to equal surface area samples of olivine, pyrite, calcite, hematite, and rutile in 0.1 M NaCl, 0.05 M pH 8.1 KHCO3 buffer. Although the mineral surfaces have widely varying points of zero charge, under these conditions they show remarkably similar adsorption of ssDNA regardless of oligomer characteristics. Mineral surfaces appear to accommodate ssDNA comparably, or ssDNA oligomers of this length are able to find binding sites of comparable strength and density due to their flexibility, despite the disparate surface properties of the different minerals. This may partially be due charge shielding by the ionic strength of the solutions tested, which are typical of many natural environments. These results may have some bearing on the adsorption and accumulation of biologically derived nucleic acids in sediments as well as the abiotic synthesis of nucleic acids before the origin of life. 相似文献
13.
Hatch L Clark C Merrick R Van Parijs S Ponirakis D Schwehr K Thompson M Wiley D 《Environmental management》2008,42(5):735-752
In 2006, we used the U.S. Coast Guard’s Automatic Identification System (AIS) to describe patterns of large commercial ship
traffic within a U.S. National Marine Sanctuary located off the coast of Massachusetts. We found that 541 large commercial
vessels transited the greater sanctuary 3413 times during the year. Cargo ships, tankers, and tug/tows constituted 78% of
the vessels and 82% of the total transits. Cargo ships, tankers, and cruise ships predominantly used the designated Boston
Traffic Separation Scheme, while tug/tow traffic was concentrated in the western and northern portions of the sanctuary. We
combined AIS data with low-frequency acoustic data from an array of nine autonomous recording units analyzed for 2 months
in 2006. Analysis of received sound levels (10–1000 Hz, root-mean-square pressure re 1 μPa ± SE) averaged 119.5 ± 0.3 dB at
high-traffic locations. High-traffic locations experienced double the acoustic power of less trafficked locations for the
majority of the time period analyzed. Average source level estimates (71–141 Hz, root-mean-square pressure re 1 μPa ± SE)
for individual vessels ranged from 158 ± 2 dB (research vessel) to 186 ± 2 dB (oil tanker). Tankers were estimated to contribute
2 times more acoustic power to the region than cargo ships, and more than 100 times more than research vessels. Our results
indicate that noise produced by large commercial vessels was at levels and within frequencies that warrant concern among managers
regarding the ability of endangered whales to maintain acoustic contact within greater sanctuary waters.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
14.
Seasonal variation and source estimation of organic compounds in urban aerosol of Augsburg, Germany 总被引:1,自引:0,他引:1
Pietrogrande MC Abbaszade G Schnelle-Kreis J Bacco D Mercuriali M Zimmermann R 《Environmental pollution (Barking, Essex : 1987)》2011,159(7):1861-1868
This study reports a general assessment of the organic composition of the PM2.5 samples collected in the city of Augsburg, Germany in a summer (August-September 2007) and a winter (February-March 2008) campaign of 36 and 30 days, respectively. The samples were directly submitted to in-situ derivatisation thermal desorption gas chromatography coupled with time of flight mass spectrometry (IDTD-GC-TOFMS) to simultaneously determine the concentrations of many classes of molecular markers, such as n-alkanes, iso- and anteiso-alkanes, polycyclic aromatic hydrocarbons (PAHs), oxidized PAHs, n-alkanoic acids, alcohols, saccharides and others.The PCA analysis of the data identified the contributions of three emission sources, i.e., combustion sources, including fossil fuel emissions and biomass burning, vegetative detritus, and oxidized PAHs. The PM chemical composition shows seasonal trend: winter is characterized by high contribution of petroleum/wood combustion while the vegetative component and atmospheric photochemical reactions are predominant in the hot season. 相似文献
15.
Pietrogrande Maria Chiara Bacco Dimitri Demaria Giorgia Russo Mara Scotto Fabiana Trentini Arianna 《Environmental science and pollution research international》2022,29(36):54391-54406
Environmental Science and Pollution Research - The concentrations of polycyclic aromatic hydrocarbons (PAHs) and quinones, a subgroup of oxygenated PAHs (oxy-PAHs), were measured in PM2.5 samples... 相似文献
16.
In a previous paper, we reported that juvenile barn swallows (Hirundo rustica) trapped during the autumn migratory season and tested in modified Emlen funnels under overcast conditions can use magnetic
information for compass orientation, although they did not orient toward the expected migratory direction. To further investigate
this behaviour, in the present paper, we report the results of two series of displacement experiments performed on juvenile
barn swallows belonging to two different roost sites [Massaciuccoli Lake (ML) and Terzo Cavone (TC)] and tested using the
same protocol as that previously adopted. On the whole, the outcome of the ML and TC experiments was quite different with
respect to (a) the degree of bird activity within the funnel (substantially lower for TC) and (b) the effect of the experimental
displacement on the directional preferences of the tested subjects (not detectable in TC, while evident in ML swallows). Taken
together, these results suggest that migrating swallows could react differently to the experimental tests depending on the
roost site where they were caught. Indeed, TC swallows, trapped in southern Italy, close to the seacoast, and characterized
by fairly large amounts of fat stores, mainly broke off their migratory activity or reoriented their directional preferences
toward inland sites, possibly in search of more profitable habitats. On the other hand, ML swallows, trapped about 660 km
to the north and characterized by lower amounts of fat stores, apparently tried to compensate for the experimental displacement.
相似文献
N. Emilio BaldacciniEmail: |
17.
Charitopoulou Maria Anna Kalogiannis Konstantinos G. Lappas Angelos A. Achilias Dimitriοs S. 《Environmental science and pollution research international》2021,28(42):59190-59213
Environmental Science and Pollution Research - The amount of plastics from waste electric and electronic equipment (WEEE) has enormously increased nowadays, due to the rapid expansion and... 相似文献
18.
In this study we use a cross-sectional survey to evaluate the nutritional response to the 1998 Bangladesh Flood Disaster by 15 relief agencies using standards developed by the Sphere Project. The Sphere Project is a recent attempt by agencies around the world to establish universal minimum standards for the purpose of ensuring quality and accountability in disaster response. The main outcomes measured were resources allocated to disaster relief types of relief activities and percentage of agencies meeting selected Sphere food aid and nutrition indicators. Although the process of nutritional response was measured, specific nutritional and health outcomes were not assessed. This review found that self-reported disaster and nutritional resources varied widely between implementing agencies, ranging from US $58,947 to $15,908,712. The percentage of resources these agencies allocated to food aid and nutritional response also varied, ranging from approximately 6 to 99 per cent of total resources. Agencies met between 8 and 83 per cent of the specific Sphere indicators which were assessed Areas in which performance was poor included preliminary nutritional analysis; beneficiary participation and feedback; disaster preparedness during non-emergency times; monitoring of local markets and impact assessment. Agencies were generally successful in areas of core humanitarian response, such as targeting the vulnerable (83 per cent) and monitoring and evaluating the process of disaster response (75 per cent). The results here identify both strengths and gaps in the quality of humanitarian response in developing nations such as Bangladesh. However, they also raise the question of implementing a rights-based approach to disaster response in nations without a commitment to meeting positive human rights in non-disaster times. 相似文献
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Dimitri Devuyst Eddy Nierynck Luc Hens Dirk Ceuterick Veerle De Baere Guido Wouters 《Environmental management》1993,17(3):395-408
Two years of experience with EIA in Flanders (northern Belgium) was evaluated in order to gain perspective on the effectiveness
of the administrative procedure. The four essential characteristics of the EIA procedure that were evaluated are: completeness,
open and public character, objectivity, and verifiability. Representatives of all parties involved in the EIA procedure were
interviewed. The result of the evaluation is a list of major problems with EIA. Recommendations for a more efficient procedure
are suggested at a time when a proposal for a new, comprehensive, and permanent EIA decree is being discussed. The evaluation
of the administrative procedure for EIA in Flanders shows that several vital characteristics of the EIA procedure are lacking.
This reduces the obligatory and open nature of the process, resulting in insufficient guarantees that the environment receives
the altention it deserves during the decision-making process. 相似文献
20.
In this paper we examine how Canadian and Flemish municipalities manage and measure sustainable development initiatives. First, we present information on how Canada, Belgium and its Flemish region introduce sustainable development initiatives at the federal and regional levels of government. The introduction at municipal level of impact assessment systems, indicator and monitoring systems, and sustainability reporting systems is discussed in general, followed by a comparison of specific case studies. In Canada, we selected the municipalities of Ottawa, Hamilton-Wentworth and Vancouver and in Flanders, the municipalities of Hasselt, Gent and Leuven. For each case study, we considered the following evaluation criteria: introduction of a long-term vision for a sustainable future; development of goals, targets and indicators; measurement of indicators; involvement and information of the local population; introduction of impact assessment and reporting systems. The discussion section deals with differences in the approach to managing and measuring sustainable development initiatives in Canada and Flanders. This study shows that sustainable development is not yet widely practised at the local level in Canada and Flanders, but Canadian municipalities have more experience with planning processes and vision development, measurement systems and public involvement. The Flemish municipalities were more inclined to go along with international campaigns dealing with local sustainability and take strong sustainable development actions which were not integrated in broader sustainable development policies. 相似文献