4,698 research outputs found
Desigualdade e Desenvolvimento: a hipótese de Kuznets é válida para os municípios brasileiros?
Pax3 synergizes with Gli2 and Zic1 in transactivating the Myf5 epaxial somite enhancer
AbstractBoth Glis, the downstream effectors of hedgehog signaling, and Zic transcription factors are required for Myf5 expression in the epaxial somite. Here we demonstrate a novel synergistic interaction between members of both families and Pax3, a paired-domain transcription factor that is essential for both myogenesis and neural crest development. We show that Pax3 synergizes with both Gli2 and Zic1 in transactivating the Myf5 epaxial somite (ES) enhancer in concert with the Myf5 promoter. This synergy is dependent on conserved functional domains of the proteins, as well as on a novel homeodomain motif in the Myf5 promoter and the essential Gli motif in the ES enhancer. Importantly, overexpression of Zic1 and Pax3 in the 10T1/2 mesodermal cell model results in enrichment of these factors at the endogenous Myf5 locus and induction of Myf5 expression. In our previous work, we showed that by enhancing nuclear translocation of Gli factors, Zics provide spatiotemporal patterning for Gli family members in the epaxial induction of Myf5 expression. Our current study indicates a complementary mechanism in which association with DNA-bound Pax3 strengthens the ability of both Zic1 and Gli2 to transactivate Myf5 in the epaxial somite
The role of corporate social responsibility in the wine industry: The case study of veneto and friuli venezia giulia
This study aimed to investigate the awareness of Corporate Social Responsibility (CSR) among wineries located in the Italian regions of Veneto and Friuli Venezia Giulia (FVG) (1), (2) the obstacles (3) and market drivers of its implementation (4), the practices and range of actions that are concretely implemented in the field of CSR (5), the implications that this management approach can have on company performance (6), and the communication tools used. The methodology adopted is based on a qualitative approach integrated with quantitative measures. In total, 28 wineries participated in the study. The results show that all of the wineries were aware of the importance of implementing CSR, although they mainly refer to environmental issues. Sponsorship in fair trade activities is considered the most relevant market driver, while Italian consumers are generally perceived as not particularly interested in sustainable wine production. The practices implemented are mainly focused on reducing environmental impact. Interesting insights have emerged from this study, such as an unusual disparity between theoretical knowledge and practical implementation of socially responsible activities, a tendency to adapt the entrepreneurial style towards CSR, as well as a fundamental willingness to implement good practices that go beyond the legal requirements currently in force
Políticas Públicas e Aprendizagem Tecnológica no Brasil: Os Casos dos Setores de Energia Elétrica e de Bens de Informática
Predicting the economic impact of an Invasive species on an Ecosystem service
Quantifying the impact of alien invasive species on ecosystem services is an essential step in developing effective practices and policy for invasive species management. Here we develop a stochastic bioeconomic model that enables the economic impact of an invasive pest to be estimated before its arrival, based on relatively poorly specified ecological and economic parameters. We developed the model by using a hypothetical invasion of the varroa bee mite (Varroa destructor) into Australia and the negative flow-on effects that it would have on pollination by reducing honey bee populations, giving rise to a loss of pollination services, reduced crop yields, and additional production costs. If the mite were to continue to be prevented from entering the country over the next 30 years, we estimate that the economic costs avoided would be US21.3-50.5 million) per year. We suggest that current invasion response funding arrangements in Australia, which do not acknowledge these avoided damages, require amendment
The evolution of the X-ray luminosity functions of unabsorbed and absorbed AGNs out to z~5
We present new measurements of the evolution of the X-ray luminosity
functions (XLFs) of unabsorbed and absorbed Active Galactic Nuclei (AGNs) out
to z~5. We construct samples containing 2957 sources detected at hard (2-7 keV)
X-ray energies and 4351 sources detected at soft (0.5-2 keV) energies from a
compilation of Chandra surveys supplemented by wide-area surveys from ASCA} and
ROSAT. We consider the hard and soft X-ray samples separately and find that the
XLF based on either (initially neglecting absorption effects) is best described
by a new flexible model parametrization where the break luminosity,
normalization and faint-end slope all evolve with redshift. We then incorporate
absorption effects, separately modelling the evolution of the XLFs of
unabsorbed () and absorbed ()
AGNs, seeking a model that can reconcile both the hard- and soft-band samples.
We find that the absorbed AGN XLF has a lower break luminosity, a higher
normalization, and a steeper faint-end slope than the unabsorbed AGN XLF out to
z~2. Hence, absorbed AGNs dominate at low luminosities, with the absorbed
fraction falling rapidly as luminosity increases. Both XLFs undergo strong
luminosity evolution which shifts the transition in the absorbed fraction to
higher luminosities at higher redshifts. The evolution in the shape of the
total XLF is primarily driven by the changing mix of unabsorbed and absorbed
populations.Comment: 36 pages, 20 figures, 11 tables. A casual reader is directed to
figures 7, 8, 9 and 20. Updated to version accepted for publication in MNRA
The MOSDEF survey: a stellar mass-SFR-metallicity relation exists at
We investigate the nature of the relation among stellar mass, star-formation
rate, and gas-phase metallicity (the M-SFR-Z relation) at high redshifts
using a sample of 260 star-forming galaxies at from the MOSDEF
survey. We present an analysis of the high-redshift M-SFR-Z relation based
on several emission-line ratios for the first time. We show that a M-SFR-Z
relation clearly exists at . The strength of this relation is similar
to predictions from cosmological hydrodynamical simulations. By performing a
direct comparison of stacks of and galaxies, we find that
galaxies have dex lower metallicity at fixed M and
SFR. In the context of chemical evolution models, this evolution of the
M-SFR-Z relation suggests an increase with redshift of the mass-loading
factor at fixed M, as well as a decrease in the metallicity of infalling
gas that is likely due to a lower importance of gas recycling relative to
accretion from the intergalactic medium at high redshifts. Performing this
analysis simultaneously with multiple metallicity-sensitive line ratios allows
us to rule out the evolution in physical conditions (e.g., N/O ratio,
ionization parameter, and hardness of the ionizing spectrum) at fixed
metallicity as the source of the observed trends with redshift and with SFR at
fixed M at . While this study highlights the promise of
performing high-order tests of chemical evolution models at high redshifts,
detailed quantitative comparisons ultimately await a full understanding of the
evolution of metallicity calibrations with redshift.Comment: 19 pages, 8 figures, accepted to Ap
The MOSDEF Survey: Kinematic and Structural Evolution of Star-Forming Galaxies at
We present ionized gas kinematics for 681 galaxies at from
the MOSFIRE Deep Evolution Field survey, measured using models which account
for random galaxy-slit misalignments together with structural parameters
derived from CANDELS Hubble Space Telescope (HST) imaging. Kinematics and sizes
are used to derive dynamical masses. Baryonic masses are estimated from stellar
masses and inferred gas masses from dust-corrected star formation rates (SFRs)
and the Kennicutt-Schmidt relation. We measure resolved rotation for 105
galaxies. For the remaining 576 galaxies we use models based on HST imaging
structural parameters together with integrated velocity dispersions and
baryonic masses to statistically constrain the median ratio of intrinsic
ordered to disordered motion, . We find that
increases with increasing stellar mass and decreasing specific SFR (sSFR).
These trends may reflect marginal disk stability, where systems with higher gas
fractions have thicker disks. For galaxies with detected rotation we assess
trends between their kinematics and mass, sSFR, and baryon surface density
(). Intrinsic dispersion correlates most with
and velocity correlates most with mass. By comparing
dynamical and baryonic masses, we find that galaxies at are
baryon dominated within their effective radii (), with Mdyn/Mbaryon
increasing over time. The inferred baryon fractions within ,
, decrease over time, even at fixed mass, size, or surface
density. At fixed redshift, does not appear to vary with
stellar mass but increases with decreasing and increasing
. For galaxies at , the median inferred baryon
fractions generally exceed 100%. We discuss possible explanations and future
avenues to resolve this tension.Comment: Accepted to ApJ. Added Figure 9, corrected sample size (main results
unchanged). 28 pages, 13 figure
SHARDS: Constraints on the dust attenuation law of star-forming galaxies at z~2
We make use of SHARDS, an ultra-deep (<26.5AB) galaxy survey that provides
optical photo-spectra at resolution R~50, via medium band filters (FWHM~150A).
This dataset is combined with ancillary optical and NIR fluxes to constrain the
dust attenuation law in the rest-frame NUV region of star-forming galaxies
within the redshift window 1.5<z<3. We focus on the NUV bump strength (B) and
the total-to-selective extinction ratio (Rv), targeting a sample of 1,753
galaxies. By comparing the data with a set of population synthesis models
coupled to a parametric dust attenuation law, we constrain Rv and B, as well as
the colour excess, E(B-V). We find a correlation between Rv and B, that can be
interpreted either as a result of the grain size distribution, or a variation
of the dust geometry among galaxies. According to the former, small dust grains
are associated with a stronger NUV bump. The latter would lead to a range of
clumpiness in the distribution of dust within the interstellar medium of
star-forming galaxies. The observed wide range of NUV bump strengths can lead
to a systematic in the interpretation of the UV slope () typically used
to characterize the dust content. In this study we quantify these variations,
concluding that the effects are ~0.4.Comment: 13 pages, 11+2 figures, 3 tables. MNRAS, in pres
- …