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201.
Long-term effects of lead poisoning on bone mineralization in vultures exposed to ammunition sources
Gangoso L Alvarez-Lloret P Rodríguez-Navarro AA Mateo R Hiraldo F Donázar JA 《Environmental pollution (Barking, Essex : 1987)》2009,157(2):569-574
Long-lived species are particularly susceptible to bioaccumulation of lead in bone tissues. In this paper we gain insights into the sublethal effects of lead contamination on Egyptian vultures (Neophron percnopterus). Our approach was done on the comparison of two populations (Canary Islands and Iberian Peninsula) differing in exposures to the ingestion of lead ammunition. Blood lead levels were higher in the island population (Canary Islands range: 5.10-1780 μg L−1n = 137; Iberian Peninsula range: 5.60-217.30 μg L−1n = 32) showing clear seasonal trends, peaking during the hunting season. Moreover, males were more susceptible to lead accumulation than females. Bone lead concentration increased with age, reflecting a bioaccumulation effect. The bone composition was significatively altered by this contaminant: the mineralization degree decreased as lead concentration levels increased. These results demonstrate the existence of long-term effects of lead poisoning, which may be of importance in the declines of threatened populations of long-lived species exposed to this contaminant. 相似文献
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204.
The gametogenesis and gonad microanatomy of the stalked barnacle Pollicipes cornucopia (Leach) is described. An histological classification of gametogenic development is proposed for the firt time for a species of the Cirripedia. This species has an annual gametogenic cycle on the north-west Spanish coast. Spawning takes place mainly from March to September. Ovaries release gametes at least twice during the gametogenic cycle. 相似文献
205.
M. C. González-González M. J. Trujillo M. Rodríguez de Alba M. García-Hoyos I. Lorda-Sánchez J. Díaz-Recasens C. Ayuso C. Ramos 《黑龙江环境通报》2003,23(3):232-234
The discovery of fetal DNA in maternal plasma from early pregnancies has led to new opportunities for clinical application. In the last few years there have been numerous reported applications, mainly fetal gender and RhD genotyping. The prenatal diagnosis of some inherited genetic diseases such as Huntington disease is also very frequently required in the prenatal diagnosis routine. We have successfully diagnosed, with a non-invasive procedure, an unaffected HD fetus at the 13th week of gestation using fetal DNA from maternal plasma and the quantitative fluorescent PCR method, which is one of the most sensitive ways to detect fetal DNA in maternal plasma at such an early time of gestation. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
206.
Rodríguez I Gumbert A Hempel de Ibarra N Kunze J Giurfa M 《Die Naturwissenschaften》2004,91(8):374-377
Bilateral symmetry has been considered as an indicator of phenotypic and genotypic quality supporting innate preferences for highly symmetric partners. Insect pollinators preferentially visit flowers of a particular symmetry type, thus leading to the suggestion that they have innate preferences for symmetrical flowers or flower models. Here we show that flower-naïve bumblebees (Bombus terrestris), with no experience of symmetric or asymmetric patterns and whose visual experience was accurately controlled, have innate preferences for bilateral symmetry. The presence of color cues did not influence the bees original preference. Our results thus show that bilateral symmetry is innately preferred in the context of food search, a fact that supports the selection of symmetry in flower displays. Furthermore, such innate preferences indicate that the nervous system of naïve animals may be primed to respond to relevant sensory cues in the environment. 相似文献
207.
Armienta MA Rodríguez R Ceniceros N Juárez F Cruz O 《Environmental pollution (Barking, Essex : 1987)》1996,91(3):391-397
Total, hexavalent and trivalent chromium were determined in surface and 30-cm depth soil samples from a highly chromium-polluted area in Guanajuato state, central México. Four samples were also analyzed by a sequential extraction procedure. Nearly 0.9 km(2) out of the 8 km(2) area sampled was polluted with chromium, at concentrations up to 12960 mg kg(-1), mostly as Cr(III). Concentrations of Cr(VI) were lower than 0.5 mg kg(-1) in most sampled points, with the exception of one, where the concentration was found to be 65.14 mg kg(-1). Chromiumcontaining dust from a chromate factory accounted for most of the contamination. The highest concentrations of hexavalent chromium in soil, were in the bottom sediments of an abandoned water reservoir used to store polluted water from a well, before use of the water in the factory process. Tannery wastes, dust from a sanitary landfill of chromate compounds and the transport of chromium products are the sources of chromium at other sites. Chromium is fixed preferentially in the hydrous Fe and Mn oxides in the more polluted soils. Less polluted soils have a high proportion of chromium associated with the sulfide and organic fraction. Cr(III) is retained preferentially in the superficial soil layer. Variations in the physical characteristics of the soil, relative abundance of the various soil components and characteristics of the contaminant source, give rise to differences in chromium soil concentrations with depth. 相似文献
208.
Social insects provide a useful model for studying the evolutionary balance between cooperation and conflict linked to genetic structure. We investigated the outcome of this conflict in the bumblebee, Bombus terrestris, whose annual colony life cycle is characterized by overt competition over male production. We established artificial colonies composed of a queen and unrelated workers by daily exchange of callow workers between colony pairs of distinct genetic make-up. Using microsatellite analysis, this procedure allowed an exact calculation of the proportion of worker-derived males. The development and social behavior of these artificial colonies were similar to those of normal colonies. Despite a high worker reproduction attempt (63.8% of workers had developed ovaries and 38.4% were egg-layers), we found that on average 95% of the males produced during the competition phase (CPh) were queen-derived. However, in four colonies, queen death resulted in a considerable amount of worker-derived male production. The different putative ultimate causes of this efficient control by the queen are discussed, and we suggest a possible scenario of an evolutionary arms race that may occur between these two female castes. 相似文献
209.
Field tests were made for the control of an olive insect pest, the olive bark beetle, Phloeotribus scarabaeoides (Col: Scolytidae), using the pyrethroid insecticide deltamethrin (D) and this insecticide combined with ethylene (D+E), an attractant of the olive bark beetle. The tests were run in olive orchards in the provinces of Granada and Jaén (Andalusia, southern Spain), treating several olive rows so as to create a barrier effect to control the pest attack. The main objective was to evaluate the arthropod fauna affected by these treatments. The different taxa captured have been separated in three different trophic groups: parasitoids, predators and phytophagous. A knock-down effect was found during the first dates in all the functional groups in all cases. The results showed the following trend in arthropod abundance: D+E>D>C. This trend was significant (p<0.05) for predators and phytophagous insects in both zones. The parasitoids of Prays oleae (Lep.: Plutellidae), a major olive pest, were most affected by the treatments, together with several groups of predators such as ants, cantharids, coccinellids and mirids. Data from the captures show the need to determine the optimum time for insecticide application in order to minimise its effect on beneficial insect populations. 相似文献
210.
Rodríguez E Martínez JL 《Journal of the Air & Waste Management Association (1995)》2005,55(6):792-802
There is global environmental concern about the pollution from industries and other organizations that should not only be controlled but also prevented. Many alternatives are available to those in charge of environmental protection, but they should be able to draw on a systematic procedure to help implement prevention and control measures. At present, there are three immediate tasks: defining the objective of any environmental study, identifying the potential pollution sources, and selecting alternatives to these sources. However, it is necessary to evaluate these alternatives by using as large a number of criteria as possible and making them cumulative so as to enable the classification and selection of the best available techniques for each pollution source. The petroleum refining industry plays an important role in the developed economies and also has a potential for pollution generation that must be controlled. The best solution for all (i.e., petroleum companies, the public, and the environment) is pollution prevention, because this option will protect all of them and will also reduce costs in terms of lower raw materials consumption as well as reducing potential fines. The procedure we have presented in this article has been applied successfully. 相似文献