5,473 research outputs found
Dealing with regional differences in data richness: an exercise applied to chub mackerel in the Iberian Peninsula.
Population structure of the European Anchovy (Engraulis encrasicolus) in ICES Division 9a: synopsis and updated information.
Genetic characterization of Acipenser sturio L., 1758 in relation to other sturgeon species using satellite DNA
We obtained and characterized a satellite (st) DNA family named HindIII from the genomes of the Adriatic sturgeon Acipenser naccarii Bonaparte, 1836, Siberian sturgeon Acipenser baerii Brandt, 1869, and beluga sturgeon Huso huso (L., 1758). We did not find this stDNA in the genome of the Atlantic sturgeon Acipenser sturio L., 1758. The comparison of sturgeon species using the HindIII stDNA revealed the following: (1) A. naccarii and A. baerii are closely related; (2) H. huso appears to belong to the genus Acipenser and, probably, Huso is not a separate genus within the Acipenserinae; (3) A. sturio differs from the other three studied species by the absence of the HindIII stDNA and, most likely, it represents a separate evolutionary lineage within the Acipenseridae. The data on the HindIII stDNA can be successfully used for species identification of sturgeon specimens captured in different European regions.En este trabajo presentamos la caracterización del genoma de Acipenser sturio L., 1758 en relación con el genoma de Acipenser naccarii Bonaparte, 1836, Acipenser baerii Brandt, 1869 y Huso huso (L., 1758) utilizando una familia de ADN satélite (la familia HindIII). Nuestro análisis revela que: (1) A. naccarii y A. baerii son especies muy emparentadas; (2) H. huso aparece muy relacionada con las especies del género Acipenser y, probablemente, podría ser considerada como una especie perteneciente a dicho género, y (3) A. sturio difiere del resto de las especies analizadas, lo que sugiere que esta especie ha debido seguir una evolución independiente respecto a las otras especies. Estos datos pueden ser muy útiles, no sólo para establecer las relaciones filogenéticas entre A. sturio y las otras especies de Acipenseridae, sino también para la identificación de ejemplares de esturiones capturados en diferentes regiones europeas.Instituto Español de Oceanografí
Three-body structure of low-lying 18Ne states
We investigate to what extent 18Ne can be descibed as a three-body system
made of an inert 16O-core and two protons. We compare to experimental data and
occasionally to shell model results. We obtain three-body wave functions with
the hyperspherical adiabatic expansion method. We study the spectrum of 18Ne,
the structure of the different states and the predominant transition strengths.
Two 0+, two 2+, and one 4+ bound states are found where they are all known
experimentally. Also one 3+ close to threshold is found and several negative
parity states, 1-, 3-, 0-, 2-, most of them bound with respect to the 16O
excited 3- state. The structures are extracted as partial wave components, as
spatial sizes of matter and charge, and as probability distributions.
Electromagnetic decay rates are calculated for these states. The dominating
decay mode for the bound states is E2 and occasionally also M1.Comment: 17 pages, 5 figures (version to appear in EPJA
Anchovy in Division 9a West (ane.27.9aN, 9aCN and 9aCS). Fishery and Surveys data: data availability and trends.
Ane.27.9a stock (Anchovy in ICES Division 9a). Southern component (Anchovy in ICES Subdivision 9a South): Fishery and Surveys data. Data availability and trends.
Ane.27.9a stock (Anchovy in ICES Division 9a). Western component (Anchovy in ICES Subdivision 9a North, Central North and Central South): Fishery and Surveys data. Data availability and trends. Alternatives for Assessment and advice.
High spatial resolution optical imaging of the multiple T Tauri system LkH{\alpha} 262/LkH{\alpha} 263
We report high spatial resolution i' band imaging of the multiple T Tauri
system LkH 262/LkH 263 obtained during the first commissioning
period of the Adaptive Optics Lucky Imager (AOLI) at the 4.2 m William Herschel
Telescope, using its Lucky Imaging mode. AOLI images have provided photometry
for each of the two components LkH 263 A and B (0.41 arcsec separation)
and marginal evidence for an unresolved binary or a disc in LkH 262.
The AOLI data combined with previously available and newly obtained optical and
infrared imaging show that the three components of LkH 263 are
co-moving, that there is orbital motion in the AB pair, and, remarkably, that
LkH 262-263 is a common proper motion system with less than 1 mas/yr
relative motion. We argue that this is a likely five-component gravitationally
bounded system. According to BT-settl models the mass of each of the five
components is close to 0.4 M and the age is in the range 1-2 Myr. The
presence of discs in some of the components offers an interesting opportunity
to investigate the formation and evolution of discs in the early stages of
multiple very low-mass systems. In particular, we provide tentative evidence
that the disc in 263C could be coplanar with the orbit of 263AB.Comment: 11 pages, 7 figures, Accepted 2016 May
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