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Author

Rui Ribeiro

Other affiliations: University of São Paulo
Bio: Rui Ribeiro is an academic researcher from University of Coimbra. The author has contributed to research in topics: Population & Daphnia magna. The author has an hindex of 35, co-authored 141 publications receiving 4109 citations. Previous affiliations of Rui Ribeiro include University of São Paulo.


Papers
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Journal ArticleDOI
TL;DR: The results support the utility of integrating responses at individual and sub-individual level to evaluate potential toxicant-induced changes in key physiological functions of H. diversicolor and to interpret their potential ecological consequences.

177 citations

Journal ArticleDOI
TL;DR: Overall results showed that avoidance tests with collembolans and earthworms have the potential to be used as screening tools in ecological risk assessment schemes for contaminated land, to trigger other tests in case of concern.
Abstract: Avoidance tests with earthworms and collembolans were conducted to demonstrate their feasibility as early screening tools for assessing the toxic potential of metal-polluted soils. Four different soils, with different degrees of metal contamination, were obtained from an abandoned mining area. All possible paired combinations were assessed for an avoidance response by the organisms. Data revealed that both species were able to avoid the most contaminated soils at the center of the ore extraction and treatment areas compared to those collected further away from the mine. However, earthworms and springtails differed in sensitivity to metals, especially when testing the two most polluted soils that had different contamination profiles. Earthworms exhibited a more consistent, less variable response than springtails. Overall results showed that avoidance tests with collembolans and earthworms have the potential to be used as screening tools in ecological risk assessment schemes for contaminated land, to trigger other tests in case of concern. However, further method development is needed to reduce variability in the data, particularly in the Collembola assays, and to gain knowledge about the possible effects of soil properties on the outcome of the tests.

176 citations

Journal ArticleDOI
TL;DR: The results suggest that the population of S. Domingos mine area and neighbour localities may be exposed to some of the elements analysed namely Mn and Zn.

171 citations

Journal ArticleDOI
TL;DR: Avoidance assays should be recommended as a complementary tool in ecological risk assessments and effluent biomonitoring because such assays can provide cost-effective and ecologically relevant information.
Abstract: Almost all terrestrial and aquatic assays that are accepted as standardized, or that have been proposed, involve the exposure of confined organisms to toxicants. If avoidance (sensu evasion, displacement) of contaminants occurs in real situations, then bioassays involving forced exposure severely underestimate pernicious effects of contamination. Two main objectives were achieved in this study: To verify the occurrence of avoidance of copper by cladocerans; to determine the association between avoidance and other toxicity endpoints (lethality and feeding depression), and therefore, to ascertain if fully acclimated individuals from a reference field population exhibited a genetically determined avoidance markedly different from those belonging to a historically metal-stressed population. Twelve cloned lineages of the cladoceran Daphnia longispina, collected from two field populations, were selected according to their lethal sensitivity to copper and acclimated to controlled conditions for more than 30 generations. A 1.1-m test chamber with five compartments was built, allowing the establishment of a dissolved toxicant gradient and the free movement of individuals. In the absence of any toxicant, juveniles from each cloned lineage distributed themselves randomly along the test chamber and furthermore, no significant differences were observed between the two replicates, attesting the repeatability of this novel assay. All lineages showed significant avoidance to copper when exposed to a gradient from 3 to 87 μg/L. The most sensitive lineages to lethal levels of copper began avoiding this metal earlier than resistant ones. An intense association was observed between other endpoints and avoidance; furthermore, avoidance was determined to be much more sensitive than lethality. Therefore, avoidance assays should be recommended as a complementary tool in ecological risk assessments and effluent biomonitoring because such assays can provide cost-effective and ecologically relevant information.

119 citations

Journal ArticleDOI
TL;DR: Although similar histopathological features were recorded in the liver and spleen of both species, the Algerian mouse has proved to be the strongest bioaccumulator species and hair was considered to be a good biological material to monitor environmental contamination of Cr in rats.

109 citations


Cited by
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Journal Article
TL;DR: For the next few weeks the course is going to be exploring a field that’s actually older than classical population genetics, although the approach it’ll be taking to it involves the use of population genetic machinery.
Abstract: So far in this course we have dealt entirely with the evolution of characters that are controlled by simple Mendelian inheritance at a single locus. There are notes on the course website about gametic disequilibrium and how allele frequencies change at two loci simultaneously, but we didn’t discuss them. In every example we’ve considered we’ve imagined that we could understand something about evolution by examining the evolution of a single gene. That’s the domain of classical population genetics. For the next few weeks we’re going to be exploring a field that’s actually older than classical population genetics, although the approach we’ll be taking to it involves the use of population genetic machinery. If you know a little about the history of evolutionary biology, you may know that after the rediscovery of Mendel’s work in 1900 there was a heated debate between the “biometricians” (e.g., Galton and Pearson) and the “Mendelians” (e.g., de Vries, Correns, Bateson, and Morgan). Biometricians asserted that the really important variation in evolution didn’t follow Mendelian rules. Height, weight, skin color, and similar traits seemed to

9,847 citations

Reference EntryDOI
31 Oct 2001
TL;DR: The American Society for Testing and Materials (ASTM) as mentioned in this paper is an independent organization devoted to the development of standards for testing and materials, and is a member of IEEE 802.11.
Abstract: The American Society for Testing and Materials (ASTM) is an independent organization devoted to the development of standards.

3,792 citations

Journal ArticleDOI
TL;DR: The influence of spray programs on the fauna of apple orchards in Nova Scotia XIV and its relation to the natural control of the oyster shell scale Lepidosaphes ulmi L.
Abstract: B6nassy, C., 1955. R6marques sur deux Aphelinid6s: Aphelinus mytilaspidis Le Baron et Aphytis proclia Walker. Annls l~piphyt. 6: 11-17. Lord, F. T. & MacPhee, A. W., 1953. The influence of spray programs on the fauna of apple orchards in Nova Scotia II. Oyster shell scale. Can. Ent. 79: 196-209. Pickett, A. D., 1946. A progress report on long term spray programs. Rep. Nova Scotia Fruit Grow. Ass. 83 : 27-31. Pickett, A. D., 1967. The influence of spray programs on the fauna of apple orchards in Nova Scotia XIV. Can. Ent. 97: 816-821. Tothill, J. D., 1918. The predacious mite Hemisarcoptes malus Shimer and its relation to the natural control of the oyster shell scale Lepidosaphes ulmi L. Agric. Gaz. Can. 5 : 234-239.

1,506 citations

Journal ArticleDOI
TL;DR: In this article, the main advantages of using microalgae for biodiesel production are described in comparison with other available feedstocks, primarily palm oil, in terms of food security and environmental impact compared to palm oil.
Abstract: Of the three generations of biodiesel feedstocks described in this paper, food crops, non-food crops and microalgae-derived biodiesel, it was found that the third generation, microalgae, is the only source that can be sustainably developed in the future. Microalgae can be converted directly into energy, such as biodiesel, and therefore appear to be a promising source of renewable energy. This paper presents a comparison between the use of microalgae and palm oil as biodiesel feedstocks. It was found that microalgae are the more sustainable source of biodiesel in terms of food security and environmental impact compared to palm oil. The inefficiency and unsustainability of the use of food crops as a biodiesel source have increased interest in the development of microalgae species to be used as a renewable energy source. In this paper, the main advantages of using microalgae for biodiesel production are described in comparison with other available feedstocks, primarily palm oil.

951 citations