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81.
82.
Nicolas Capelli Francisco Barja Diederik Van Tuinen Jean Monnat Gilbert Turian Ruben Ortega Perez 《FEMS microbiology letters》1997,147(2):215-220
We have enriched a 47-kDa polypeptide (p47) from Neurospora crassa on the basis of its affinity to calmodulin. The p47 was purified to homogeneity by chromatography on a Mono S cation exchange column and evidence is presented that the polypeptide co-sediments specifically with F-actin. The intracellular distribution of p47 and actin was also examined using indirect double immunofluorescence staining of cells at different stages of development. Our results suggest that by altering the conformation binding site of actin to p47, calmodulin could play a regulatory role in the polarized hyphal growth of N. crassa. 相似文献
83.
Claude R. Joiris Eva Falck Diederik D’Hert Simon Jungblut Karin Boos 《Polar Biology》2014,37(11):1645-1657
The distribution at sea of upper trophic levels—seabirds and marine mammals—is depending on their food availability: high concentrations reflect high prey abundance and thus high biological production. Polar marine ecosystems are characterized by low biodiversity and high biological patchiness. The distribution of predators, as a consequence, shows a similar patchiness. During two expeditions of icebreaking RV Polarstern in June–July 2011, biodiversity in the arctic marine zone north of 70°N was very low, with low numbers of species: 20 seabirds, eight cetaceans, five pinnipeds and polar bear. Moreover, a few species accounted for the majority in numbers: four bird species for 95 % of the total of 23,000 seabirds recorded during 700 transect counts: fulmar Fulmarus glacialis, kittiwake Rissa tridactyla, Brünnich’s guillemot Uria lomvia and little auk Alle alle. Among the marine mammals, 250 fin whales Balaenoptera physalus accounted for 80 % of the identified large cetaceans, 270 white-beaked dolphin Lagenorhynchus albirostris for 100 % of the small cetaceans and 180 harp seals Pagophilus groenlandica for 80 % of the identified pinnipeds. Their quantitative distribution was depending on water masses and oceanic fronts, large cetaceans—mainly fin whales—showing an important aggregation on the shelf slope off western Spitsbergen, as well as little auks and Brünnich’s guillemots. So that this zone, shelf slope and front of mixed Arctic/Atlantic Waters, showed unusually high seabird and cetacean concentrations. Seasonal factors possibly influencing their distribution are addressed. 相似文献
84.
Pant Rana Van Hoof Gert Schowanek Diederik Feijtel Tom C. J. de Koning Arjan Hauschild Michael Olsen Stig I. Pennington David W. Rosenbaum Ralph 《The International Journal of Life Cycle Assessment》2004,9(5):295-306
Background and Objective In the OMNIITOX project 11 partners have the common objective to improve environmental management tools for the assessment
of (eco)toxicological impacts. The detergent case study aims at: i) comparing three Procter &c Gamble laundry detergent forms
(Regular Powder-RP, Compact Powder-CP and Compact Liquid-CL) regarding their potential impacts on aquatic ecotoxicity, ii)
providing insights into the differences between various Life Cycle Impact Assessment (LCIA) methods with respect to data needs
and results and iii) comparing the results from Life Cycle Assessment (LCA) with results from an Environmental Risk Assessment
(ERA).
Material and Methods The LCIA has been conducted with EDIP97 (chronic aquatic ecotoxicity) [1], USES-LCA (freshwater and marine water aquatic ecotoxicity,
sometimes referred to as CML2001) [2, 3] and IMPACT 2002 (covering freshwater aquatic ecotoxicity) [4]. The comparative product
ERA is based on the EU Ecolabel approach for detergents [5] and EUSES [6], which is based on the Technical Guidance Document
(TGD) of the EU on Environmental Risk Assessment (ERA) of chemicals [7]. Apart from the Eco-label approach, all calculations
are based on the same set of physico-chemical and toxicological effect data to enable a better comparison of the methodological
differences. For the same reason, the system boundaries were kept the same in all cases, focusing on emissions into water
at the disposal stage.
Results and Discussion Significant differences between the LCIA methods with respect to data needs and results were identified. Most LCIA methods
for freshwater ecotoxicity and the ERA see the compact and regular powders as similar, followed by compact liquid. IMPACT
2002 (for freshwater) suggests the liquid is equally as good as the compact powder, while the regular powder comes out worse
by a factor of 2. USES-LCA for marine water shows a very different picture seeing the compact liquid as the clear winner over
the powders, with the regular powder the least favourable option. Even the LCIA methods which result in die same product ranking,
e.g. EDIP97 chronic aquatic ecotoxicity and USES-LCA freshwater ecotoxicity, significantly differ in terms of most contributing
substances. Whereas, according to IMPACT 2002 and USES-LCA marine water, results are entirely dominated by inorganic substances,
the other LCIA methods and the ERA assign a key role to surfactants. Deviating results are mainly due to differences in the
fate and exposure modelling and, to a lesser extent, to differences in the toxicological effect calculations. Only IMPACT
2002 calculates the effects based on a mean value approach, whereas all other LCIA methods and the ERA tend to prefer a PNEC-based
approach. In a comparative context like LCA the OMNIITOX project has taken the decision for a combined mean and PNEC-based
approach, as it better represents the ‘average’ toxicity while still taking into account more sensitive species. However,
the main reason for deviating results remains in the calculation of the residence time of emissions in the water compartments.
Conclusion and Outlook The situation that different LCIA methods result in different answers to the question concerning which detergent type is to
be preferred regarding the impact category aquatic ecotoxicity is not satisfactory, unless explicit reasons for the differences
are identifiable. This can hamper practical decision support, as LCA practitioners usually will not be in a position to choose
the ’right’ LCIA method for their specific case. This puts a challenge to the entire OMNIITOX project to develop a method,
which finds common ground regarding fate, exposure and effect modelling to overcome the current situa-tion of diverging results
and to reflect most realistic conditions. 相似文献
85.
Aim Invasive alien species are a growing threat to biodiversity, and identifying the mechanisms that enable these species to establish viable populations in their new environment is paramount for management of the problems they pose. Using an unusually large number of both failed and successful documented introductions of parakeets (Aves: Psittacidae) in Europe, we test two of the major hypotheses on the establishment success of invading species, namely the climate‐matching and the human‐activity hypothesis. Location European human population centres where ring‐necked parakeet (Psittacula krameri) and/or monk parakeet (Myiopsitta monachus) introductions have occurred. Methods Data on ring‐necked and monk parakeet introductions in Europe were gathered from various sources, including published books and articles, but also from unpublished reports and local grey literature. Information was verified with experts from the region under consideration. In order to test the climate‐matching hypothesis, we verified whether the climatic factors that determine the parakeets’ native ranges also explain establishment success in Europe. Parakeet occurrence data from the native ranges were analysed using the presence‐only modelling method Maxent , and correlations between parakeet establishment and climatic and anthropogenic variables in Europe were assessed using both stepwise logistic regression and the information‐theoretic model selection approach. Results The establishment success of ring‐necked and monk parakeets was found to be positively associated with human population density, and, both in the native and in the introduced regions, parakeet occurrence was negatively correlated with the number of frost days. Thus, parakeets are more likely to establish in warmer and human‐dominated areas. Main conclusions The large number of independent parakeet introductions in Europe allows us to test the often‐used climate‐matching and human‐activity hypotheses at the species level. We show that both hypotheses offer insight into the invasion process of monk and ring‐necked parakeets. Our results suggest that, in the future, parakeet establishment probability may increase even further because global warming is likely to cause a decrease in the number of frost days and because urbanization and human populations are still increasing. 相似文献
86.
87.
Summary An improved auto-analyzer method for the quantitative determination of phosphonate-phosphorus was developed. Its advantages are of three sorts: 1) phosphonates can be determined in a variety of media, even with high levels of organic compounds, 2) viscous bacterial broths can be analysed directly on the auto-analyzer, 3) the method has an increased sensitivity. 相似文献
88.
Paul Arens Carmen Mansilla Daniël Deinum Laetitia Cavellini André Moretti Sophie Rolland Hanneke van der Schoot David Calvache Fernando Ponz Cécile Collonnier René Mathis Diederik Smilde Carole Caranta Ben Vosman 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,120(3):655-664
Molecular markers linked to phenotypically important traits are of great interest especially when traits are difficult and/or costly to be observed. In tomato where a strong focus on resistance breeding has led to the introgression of several resistance genes, resistance traits have become important characteristics in distinctness, uniformity and stability (DUS) testing for Plant Breeders Rights (PBR) applications. Evaluation of disease traits in biological assays is not always straightforward because assays are often influenced by environmental factors, and difficulties in scoring exist. In this study, we describe the development and/or evaluation of molecular marker assays for the Verticillium genes Ve1 and Ve2, the tomato mosaic virus Tm1 (linked marker), the tomato mosaic virus Tm2 and Tm2 2 genes, the Meloidogyne incognita Mi1-2 gene, the Fusarium I (linked marker) and I2 loci, which are obligatory traits in PBR testing. The marker assays were evaluated for their robustness in a ring test and then evaluated in a set of varieties. Although in general, results between biological assays and marker assays gave highly correlated results, marker assays showed an advantage over biological tests in that the results were clearer, i.e., homozygote/heterozygote presence of the resistance gene can be detected and heterogeneity in seed lots can be identified readily. Within the UPOV framework for granting of PBR, the markers have the potential to fulfil the requirements needed for implementation in DUS testing of candidate varieties and could complement or may be an alternative to the pathogenesis tests that are carried out at present. 相似文献
89.
Arjan de Koning Diederik Schowanek Joost Dewaele Annie Weisbrod Jeroen Guinée 《The International Journal of Life Cycle Assessment》2010,15(1):79-89
Background, aim, and scope
A new trend driven by climate change concerns is the interest to label consumer products with a carbon footprint (CF) number. Here, we present a study that examines the uncertainty in the estimated CFs of a liquid and a compact powder detergent and how the uncertainty varies with the type of comparison one wishes to make. 相似文献90.