27 research outputs found
Multiple Distant Origins for Green Sea Turtles Aggregating off Gorgona Island in the Colombian Eastern Pacific
Mitochondrial DNA analyses have been useful for resolving maternal lineages and migratory behavior to foraging grounds (FG) in sea turtles. However, little is known about source rookeries and haplotype composition of foraging green turtle aggregations in the southeastern Pacific. We used mitochondrial DNA control region sequences to identify the haplotype composition of 55 green turtles, Chelonia mydas, captured in foraging grounds of Gorgona National Park in the Colombian Pacific. Amplified fragments of the control region (457 bp) revealed the presence of seven haplotypes, with haplotype (h) and nucleotide (π) diversities of h = 0.300±0.080 and π = 0.009±0.005 respectively. The most common haplotype was CMP4 observed in 83% of individuals, followed by CMP22 (5%). The genetic composition of the Gorgona foraging population primarily comprised haplotypes that have been found at eastern Pacific rookeries including Mexico and the Galapagos, as well as haplotypes of unknown stock origin that likely originated from more distant western Pacific rookeries. Mixed stock analysis suggests that the Gorgona FG population is comprised mostly of animals from the Galapagos rookery (80%). Lagrangian drifter data showed that movement of turtles along the eastern Pacific coast and eastward from distant western and central Pacific sites was possible through passive drift. Our results highlight the importance of this protected area for conservation management of green turtles recruited from distant sites along the eastern Pacific Ocean
Síndromes muy poco frecuentes
Dismorfología, Citogenética y Clínica: Resultados de estudios sobre los datos del ECEMCSince the year 2002, this Section of the Boletín del ECEMC: Revista de Dismorfología y Epidemiología, is dedicated to dysmorphology, cytogenetics and clinical analysis of congenital anomalies, and includes a chapter on syndromes with very low frequency. The aim of this chapter is to summarize the most important characteristics, the etiology, and the mechanisms involved in the selected syndromes. The low frequency of these syndromes, together with their probable decreasing birth prevalence due to the impact of prenatal diagnosis, imply that pediatricians and other health professionals would have less opportunity to know their clinical characteristics. This circumstance together with the overlapping of the clinical features among some of the syndromes, make difficult to perform an early diagnosis, which is important for genetic counselling, and to provide the most suitable treatment to each pacient. The syndromes included are: Aarskog, Freeman-Sheldon, Cleidocranial dysplasia, Noonan, Cardio-Facio-Cutaneous and Costello. In addition, a short summary about the differential diagnosis among Noonan, Cardio-Facio-Cutaneous and Costello syndromes is also included.N
Valence-state reflectometry of complex oxide heterointerfaces
Emergent phenomena in transition-metal-oxide heterostructures such as interface superconductivity and magnetism have been attributed to electronic reconstruction, which, however, is difficult to detect and characterise. Here we overcome the associated difficulties to simultaneously address the electronic degrees of freedom and distinguish interface from bulk effects by implementing a novel approach to resonant X-ray reflectivity (RXR). Our RXR study of the chemical and valance profiles along the polar (001) direction of a LaCoO3 film on NdGaO3 reveals a pronounced valence-state reconstruction from Co3+ in the bulk to Co2+ at the surface, with an areal density close to 0.5 Co2+ ions per unit cell. An identical film capped with polar (001) LaAlO3 maintains the Co3+ valence over its entire thickness. We interpret this as evidence for electronic reconstruction in the uncapped film, involving the transfer of 0.5e− per unit cell to the subsurface CoO2 layer at its LaO-terminated polar surface