165 research outputs found
Comércio ilegal de aves nativas em plataforma social virtual: subsídios para a perícia ambiental.
A retirada de animais da natureza e o tráfico de animais oferecem uma grande ameaça a biodiversidade. O livre comércio em plataformas sociais está ocupando um lugar notório na sociedade e para isso, nota-se a necessidade de profissionais com conhecimentos técnico-científicos para auxiliar no combate ao tráfico de animais e nos processos judiciais. O objetivo deste estudo foi reconhecer o comércio ilegal de aves nativas do Rio Grande do Sul em uma plataforma social, e avaliar seu uso como ferramenta para perícias ambientais. Foram monitorados, durante um mês, três grupos de comércio de aves na plataforma Facebook®. Os dados obtidos foram: espécie nativa ou exótica do Rio Grande do Sul, valor de venda, presença de anilha e espécies mais anunciadas. Contabilizou-se 338 anúncios, comercializando 36 espécies. Os valores variaram de R 1.500,00 o espécime. Quatro espécies apresentam algum grau de ameaça de extinção. Seis espécies representaram 70% dos anúncios. Para os peritos ambientais e investigadores criminais, esta modalidade de comércio proporciona uma ferramenta válida para atuarem de forma mais acentuada e eficaz. Estes locais além de expor os criminosos, podem fornecer informações valiosas para o combate ao tráfico de animais silvestres
Diversidade de plantas de quinoa, cultivar brs pirabiru, na produção de sementes, no sul do Brasil.
Stellar populations of bulges at low redshift
This chapter summarizes our current understanding of the stellar population
properties of bulges and outlines important future research directions.Comment: Review article to appear in "Galactic Bulges", Editors: Laurikainen
E., Peletier R., Gadotti D., Springer Publishing. 34 pages, 12 figure
Produção de sementes de quinoa no sul do Brasil: variabilidade de plantas da cultivar BRS Piabiru.
Germinação de sementes de quinoa submetidas a diferentes temperaturas.
bitstream/item/161663/1/Boletim-245.pd
The Fornax3D project: Environmental effects on the assembly of dynamically cold disks in Fornax cluster galaxies
We apply a population-orbit superposition method to 16 galaxies in the Fornax
cluster observed with MUSE/VLT in the context of the Fornax3D project. By
fitting the luminosity distribution, stellar kinematics, and age and
metallicity maps simultaneously, we obtained the internal stellar orbit
distribution, as well as the age and metallicity distribution of stars on
different orbits for each galaxy. Based on the model, we decompose each galaxy
into a dynamically cold disk (orbital circularity ) and a
dynamically hot non-disk component (orbital circularity ), and
obtain the surface-brightness, age, and metallicity radial profiles of each
component. The galaxy infall time into the cluster is strongly correlated with
galaxy cold-disk age with older cold disks in ancient infallers. We quantify
the infall time of each galaxy with its cold-disk age using a
correlation calibrated with TNG50 cosmological simulations. For galaxies in the
Fornax cluster, we found that the luminosity fraction of cold disk in galaxies
with Gyr are a factor of lower than in more recent
infallers while controlling for total stellar mass. Nine of the 16 galaxies
have spatially extended cold disks, and most of them show positive or zero age
gradients; stars in the inner disk are Gyr younger than that in the
outer disk, in contrast to the expectation of inside-out growth. Our results
indicate that the assembly of cold disks in galaxies is strongly affected by
their infall into clusters, by either removal of gas in outer regions or even
tidally stripping or heating part of the pre-existing disks. Star formation in
outer disks can stop quickly after the galaxy falls into the cluster, while
star formation in the inner disks can last for a few Gyrs more, building the
positive age gradient measured in cold disks.Comment: 31 pages, 32 figures, Accepted to A&
Boxy/peanut/X bulges, barlenses and the thick part of galactic bars: What are they and how did they form?
Bars have a complex three-dimensional shape. In particular their inner part
is vertically much thicker than the parts further out. Viewed edge-on, the
thick part of the bar is what is commonly known as a boxy-, peanut- or X- bulge
and viewed face-on it is referred to as a barlens. These components are due to
disc and bar instabilities and are composed of disc material. I review here
their formation, evolution and dynamics, using simulations, orbital structure
theory and comparisons to observations.Comment: 21 pages, 7 figures, invited review to appear in "Galactic Bulges",
E. Laurikainen, R. Peletier, D. Gadotti, (eds.), Springe
The Milky Way Bulge: Observed properties and a comparison to external galaxies
The Milky Way bulge offers a unique opportunity to investigate in detail the
role that different processes such as dynamical instabilities, hierarchical
merging, and dissipational collapse may have played in the history of the
Galaxy formation and evolution based on its resolved stellar population
properties. Large observation programmes and surveys of the bulge are providing
for the first time a look into the global view of the Milky Way bulge that can
be compared with the bulges of other galaxies, and be used as a template for
detailed comparison with models. The Milky Way has been shown to have a
box/peanut (B/P) bulge and recent evidence seems to suggest the presence of an
additional spheroidal component. In this review we summarise the global
chemical abundances, kinematics and structural properties that allow us to
disentangle these multiple components and provide constraints to understand
their origin. The investigation of both detailed and global properties of the
bulge now provide us with the opportunity to characterise the bulge as observed
in models, and to place the mixed component bulge scenario in the general
context of external galaxies. When writing this review, we considered the
perspectives of researchers working with the Milky Way and researchers working
with external galaxies. It is an attempt to approach both communities for a
fruitful exchange of ideas.Comment: Review article to appear in "Galactic Bulges", Editors: Laurikainen
E., Peletier R., Gadotti D., Springer Publishing. 36 pages, 10 figure
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