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981.
Ana V. Leitão Anabela H. Monteiro Paulo G. Mota 《Behavioral ecology and sociobiology》2014,68(1):63-72
Avian plumage colouration is one of the most impressive displays in nature and is frequently used as sexual signal. There is now considerable evidence that females consistently prefer males with the most elaborated colour displays. Bird colour vision expands into the ultraviolet (UV) range, which prompted several studies to test the importance of UV in mate choice, revealing that females are affected by the UV light component. These studies were mostly performed on structural plumage, whereas carotenoid-based plumage was rarely considered, although it also has a typical reflection peak in the UV. Our study tested the female choice over male yellow colouration, and whether it is influenced by UV removal, in the European serin (Serinus serinus), a sexually dichromatic cardueline finch, with males showing a conspicuous carotenoid-based yellow plumage. We shows that females preferred yellower males and that male attractiveness was lost when the UV colouration was blocked, with either of the UV-blocking techniques used. The results of our study indicate that the UV component of carotenoid colouration is important in the female mate assessment in serins and highlights the importance of considering colour perception in avian mate choice. 相似文献
982.
A simple and rapid method has been optimised to determine glyoxal and methylglyoxal in atmospheric particulate matter by extraction and derivatisation with 2,4-dinitrophenylhydrazine solutions. Minimal sample preparation was required by mixing a portion of filter charged with atmospheric particulate matter with 5?mL of a saturated solution of 2,4-dinitrophenylhydrazine (1.6?g?L?1) in acetonitrile and acidified by H2SO4 (50?µL?L?1). Chromatographic analyses were carried out 1?h after derivatisation solution was mixed. Finally, the proposed method was applied to quantify these dicarbonyls in atmospheric particulate matter samples, which were obtained as part of a large field study to characterise atmospheric aerosol from a rural area of Madrid. Glyoxal concentrations averaged 0.24?ng?m?3, whereas mean values of methyl glyoxal were around 0.95?ng?m?3. Methyl glyoxal levels showed a clear relationship with the particulate matter levels, whereas glyoxal data did not show such a correlation. This could indicate that both dicarbonyls come from different sources. 相似文献
983.
Ernesto Bonilla Rocío Contreras Shirley Medina-Leendertz Marylu Mora Virginia Villalobos Milagros Paz 《毒物与环境化学》2013,95(4):742-747
The effect of resveratrol was studied on the life span and motor activity of Drosophila melanogaster treated with manganese (Mn). Two days after emerging from the pupa, male wild type D. melanogaster were fed for 13 days with corn media containing 15?mM Mn. Thereafter, Drosophila were divided into six groups of 300 flies each: (1) the flies remained treated with Mn; (2) began treatment with 0.43?mM resveratrol (Mn-resveratrol group); (3) received no additional treatment (Mn-no treatment group); (4) simultaneously fed with Mn and resveratrol (Mn?+?resveratrol group). In addition, a control (5) with no treatment and another group (6) fed only with resveratrol after emerging from the pupa were included. All Mn-treated flies (group 1) were dead on the 25th day. The life span in the resveratrol group was 91?±?0.33 days (mean?±?S.E.M.) and in Mn-resveratrol flies was 83?±?2 days. These two values were significantly higher than those detected in the control (5) and Mn-no treatment (group 3) flies whose life span were 68?±?0.33 and 67?±?2.31 days, respectively. The Mn?+?resveratrol-fed flies had a markedly higher life span (31?±?1.53 days) than Mn-fed flies (23?±?0.88 days). In the flies that received Mn (Mn and Mn?+?resveratrol groups), the motor activity decreased significantly with respect to control (groups 5) and the Mn–resveratrol and resveratrol groups. In conclusion, resveratrol increased significantly the life span of Mn-treated D. melanogaster. 相似文献
984.
Thalita B. Zanoni Eloísa Silva de Paula Guilherme Julião Zocolo Maria Valnice B. Zanoni Danielle Palma de Oliveira 《毒物与环境化学》2013,95(9):1506-1517
Incubation of guanosine and Sudan III induces the formation of a stable adduct, which may be identified using a spectrophotometric technique and mass spectroscopy. The high nucleophilicity of the C8 position and its proximity to N7 makes the site susceptible to a nucleophilic attack, which explains the SN2 reaction detected between guanosine and Sudan III dye. In addition, direct interaction of Sudan III with calf thymus DNA was monitored using a simple spectrophotometric technique. The results presented indicate that a simple modification of the chemical structure of Sudan I (monoazo dye) to Sudan III (diazo dye) markedly alters reactivity towards nitrogenous DNA bases. 相似文献
985.
João Porteiro Helena Calado Margarida Pereira Adriano Quintela Tomáz Dentinho 《国际发展与全球生态学杂志》2013,20(2):192-200
The Sete Cidades Lake (437 ha) is located in a volcanic crater of São Miguel Island (Azores). The watershed is 1923 ha, and 25% of it is covered with water. Extreme logging and the use of fertilizers in the cattle grazing areas have caused sedimentation and eutrophication of the main water body (Carlson Trophic State Index TSI = 40–50 mesoeutrophy). To deal with the issue, a linear programming model was created to generate efficient land-use scenarios for different amounts of phosphorus release. The model was calibrated for the present situation and then simulated to obtain 29 scenarios. It allowed us to derive parameters for each scenario. Then a multiobjective program was used to derive an acceptable weight for each indicator. The dominant solutions were discovered and discussed with different stakeholders. 相似文献
986.
Identifying and mapping local bycatch hotspots of loggerhead sea turtles using a GIS-based method: implications for conservation 总被引:1,自引:0,他引:1
Giulia Cambiè Noela Sánchez-Carnero Toni Mingozzi Ramón Muiño Juan Freire 《Marine Biology》2013,160(3):653-665
Fisheries bycatch of marine megafauna is a worldwide conservation issue. In this study, we propose a method for generating reliable maps of sea turtle bycatch hotspots. Based on a well-defined area of fishing effort determined from the longline sets monitored in 2007 and 2010, we calculated the fishing area with the highest turtle bycatch density for both years. Our results show that it is important to consider all the components of fishing effort (area, number of hooks and soak time) in order to standardize the bycatch events, and thus the spatial density of the captures can be considered an index of abundance and aggregation of the species. Moreover, the high-resolution level of the analyses was useful for investigating the cumulative effect of the longline sets, which often overlap, and made it possible to correctly map the capture density and the intensity of the fishing effort at any given location. 相似文献
987.
Tanya M. Silveira Catarina Frazão Santos Francisco Andrade 《Journal of Coastal Conservation》2013,17(4):825-832
In the winter of 2006/2007 approximately 200,000 m3 of high quality sand from the dredging of the local marina were placed at the ocean-side beaches in the vicinity of a tourism development in Tróia, Portugal. The beach-quality sediment provided a source of “sand of opportunity” which was used to increase the dry-beach width of the highly used coastal stretch. The sediment was placed along approximately 600 m of shoreline and a monitoring program has since being carried out twice a year. High-resolution topographic surveys and sediment analysis are being conducted to evaluate the performance and response of the fill to the local forcing factors and ultimately to evaluate the effectiveness of the fill project. Two years after the nourishment, the sediment has been distributed both cross-shore and alongshore. The pre-nourishment beach slope was attained and the new shoreline has acquired a natural shape. Berm width increased by a maximum of 100 m, and a set of new dune ridges has developed, due to sand accumulation promoted by the settlement of vegetation. In conclusion, 2 years after its completion, the beach nourishment in Tróia can be viewed as a successful project in which the beneficial use of dredged material resulted in: 1) area for increased dune field growth and development, 2) enhancement of potential shorebird nesting areas and habitat, and 3) increased area for recreation purposes. 相似文献
988.
P. C. Roebeling L. Costa L. Magalhães-Filho V. Tekken 《Journal of Coastal Conservation》2013,17(3):389-395
Coastal zones experience increased rates of coastal erosion, due to rising sea levels, increased storm surge frequencies, reduced sediment delivery and anthropogenic transformations. Yet, coastal zones host ecosystems that provide associated services which, therefore, may be lost due to coastal erosion. In this paper we assess to what extent past and future coastal erosion patterns lead to losses in land cover types and associated ecosystem service values. Hence, historical (based on CORINE land cover information) and projected (based on Dynamic and Interactive Vulnerability Assessment - DIVA - simulations) coastal erosion patterns are used in combination with a benefits transfer approach. DIVA projections are based on regionalized IPCC scenarios. Relative to the period 1975–2050, a case study is provided for selected European coastal country member states. For historical (1975–2006) coastal erosion trends, we observe territory losses in coastal agricultural, water body and forest & semi-natural areas – total coastal erosion equaling over 4,500 km2. Corresponding coastal ecosystem service values decrease from about €22.3 billion per year in 1975 to about €21.6 billion per year in 2006. For future (2006–2050) coastal erosion projections, total territory losses equal between ~3,700 km2 and ~5,800 km2 – coastal wetland areas being affected most severely. Corresponding coastal ecosystem service values decrease to between €20.1 and €19.4 billion per year by 2050. Hence, we argue that the response strategy of EU member states to deal with coastal erosion and climate change impacts should be based on the economic as well as the ecological importance of their coastal zones. 相似文献
989.
Araceli Loredo-Treviño Gerardo Gutiérrez-Sánchez Raúl Rodríguez-Herrera Cristóbal N. Aguilar 《Journal of Polymers and the Environment》2012,20(1):258-265
Plastics are present in a lot of aspects of everyday life. They are very versatile and resistant to microbial attack. Polyurethanes
are used in several industries and are divided in polyester and polyether polyurethanes and there are different types among
them. Despite their microbial resistance, they are susceptible to the attack of fungi and bacteria but the mechanism to elucidate
its biodegradation are unknown. There are reports from bacteria and fungi that are capable of degrading polyurethane but the
studies about the enzymes that attack the plastic are focused on bacterial enzymes only. The enzymes reported are of type
esterase and protease mainly since these enzymes are very unspecific and can recognize some regions in the polyurethane molecule
and hydrolyze it. Fungal enzymes have been studied prior the 1990s decade but recently, some authors report the use of filamentous
fungi to degrade polyurethane and also report some characteristics of the enzymes involved in it. This review approaches polyurethane
biodegradation by focusing on the enzymes reported to date. 相似文献
990.
Nini Johanna Cadena Camilo Rey Marcela Hernández-Hoyos J. Darío Sánchez Stanislas Teillaud Nestor Ardila Juan A. Sánchez 《Marine Biology》2010,157(5):1003-1010
Branching growth is present both in plants and animals, either marine or terrestrial. Although cellular and other modular
levels of organization in plants and animals have evolved through different molecular and physiological mechanisms, several
aspects of their branching modular system and morphology are similar. We studied vessel organization and colony integration,
in order to comprehend underlying relationships between different structural components in a gorgonian coral network. The
theoretical formalism was validated in the gorgonian coral Eunicea mammosa (Plexauridae, Octocorallia) in Belize. As in vascular plants, these colonial animals create a complex network of connections
among modular branches integrated in stem canals downstream toward the base. A new formalism is proposed for describing gorgonian
branching. A global property of a colony is for instance the size of its base or its weight whereas a local property is the
size of branch in a particular place of the colony. However, a global property is not the simple addition of local modular
properties, as the case of stem canals in the colony base. Theoretically, the process of branching is tightly intertwined
with the internal network organization. The colony network centralization is driven by a linear relationship between the total
number of branches and the stem canals at the base of the colony. If stem canals play important roles in the transport of
nutrients throughout the colony and the biomechanical support from the base up to the tips, we can assume that there is an
underlying association between the number of stem canals at the base and the number of for example, terminal branches. These
associations may provide new findings that extend our understanding of the functional organization of tree-like networks in
octocorals and their vascular systems. The idea that the external components of a tree-like plant network are directly correlated
and connected down to the main trunk seems to be analogous in an animal system. 相似文献