86 research outputs found
Identificação molecular de filés de pescado do gênero Pseudoplatystoma baseada na técnica de PCR-Multiplex.
Magnetic field and wind of Kappa Ceti: towards the planetary habitability of the young Sun when life arose on Earth
We report magnetic field measurements for Kappa1~Cet, a proxy of the young
Sun when life arose on Earth. We carry out an analysis of the magnetic
properties determined from spectropolarimetric observations and reconstruct its
large-scale surface magnetic field to derive the magnetic environment, stellar
winds and particle flux permeating the interplanetary medium around Kappa1~Cet.
Our results show a closer magnetosphere and mass-loss rate of Mdot = 9.7 x
10^{-13} Msol/yr, i.e., a factor 50 times larger than the current solar wind
mass-loss rate, resulting in a larger interaction via space weather
disturbances between the stellar wind and a hypothetical young-Earth analogue,
potentially affecting the planet's habitability. Interaction of the wind from
the young Sun with the planetary ancient magnetic field may have affected the
young Earth and its life conditionsComment: 6 pages, 5 figures, Published at the Astrophysical Journal Letters
(ApJL): Manuscript #LET3358
Genetic identification of interspecific hybrid of Neotropical catfish species (Pseudoplatystoma corruscans vs. Pseudoplatystoma reticulatum) in rivers of Mato Grosso do Sul State, Brazil
On the link between rotation, chromospheric activity and Li abundance in subgiant stars
The connection rotation-CaII emission flux-lithium abundance is analyzed for
a sample of bona fide subgiant stars, with evolutionary status determined from
HIPPARCOS trigonometric parallax measurements and from the Toulouse-Geneva
code.Comment: 9 pages, 8 figure
Magnetic field and wind of Kappa Ceti: toward the planetary habitability of the young sun when life arose on earth
We report magnetic field measurements for κ1 Cet, a proxy of the young Sun when life arose on Earth. We carry out an analysis of the magnetic properties determined from spectropolarimetric observations and reconstruct the
large-scale surface magnetic field to derive the magnetic environment, stellar winds, and particle flux permeating
the interplanetary medium around k1 Cet. Our results show a closer magnetosphere and mass-loss rate of M = 9.7 ́ 10-13 M yr-1, i.e., a factor of 50 times larger than the current solar wind mass-loss rate, resulting in a larger interaction via space weather disturbances between the stellar wind and a hypothetical young-Earth analogue, potentially affecting the planet’s habitability. Interaction of the wind from the young Sun with the planetary ancient magnetic field may have affected the young Earth and its life conditions
Alimentos e alimentação.
O objetivo deste capítulo é apresentar as principais etapas dos processos de conservação de forragens, bem como as características dos principais alimentos disponíveis na Região Amazônica. Com base nessas informações, serão apresentadas orientações técnicas para formulação de misturas concentradas, bem como para a alimentação e suplementação mineral e vitamínica dos rebanhos leiteiros da região.bitstream/item/217365/1/cpafro-18466.pd
Age and mass of solar twins constrained by lithium abundance
We analyze the non-standard mixing history of the solar twins HIP 55459, HIP
79672, HIP 56948, HIP 73815, and HIP 100963, to determine as precisely as
possible their mass and age. We computed a grid of evolutionary models with
non-standard mixing at several metallicities with the Toulouse-Geneva code for
a range of stellar masses assuming an error bar of +-50K in Teff. We choose the
evolutionary model that reproduces accurately the observed low lithium
abundances observed in the solar twins. Our best-fit model for each solar twin
provides a mass and age solution constrained by their Li content and Teff
determination. HIP 56948 is the most likely solar-twin candidate at the present
time and our analysis infers a mass of 0.994 +- 0.004 Msun and an age of 4.71
+-1.39 Gyr. Non-standard mixing is required to explain the low Li abundances
observed in solar twins. Li depletion due to additional mixing in solar twins
is strongly mass dependent. An accurate lithium abundance measurement and
non-standard models provide more precise information about the age and mass
more robustly than determined by classical methods alone.Comment: 10 pages, 5 figures, Accepted for publication in Astronomy and
Astrophysic
Caracterização da função do gene FLC-LIKE durante a transição da ENDO- para dormência na macieira.
The MADS-box MdFLC-like gene was previously described within the major QTL for time of bud break in apple chromosome Chr09, and its expression gradually increases towards dormancy release
Brain metabolism and cerebrospinal fluid biomarkers profile of non-amnestic mild cognitive impairment in comparison to amnestic mild cognitive impairment and normal older subjects
Abstract\ud
\ud
Introduction\ud
Mild cognitive impairment (MCI) is classically considered a transitional stage between normal aging and dementia. Non-amnestic MCI (naMCI) patients, however, typically demonstrate cognitive deficits other than memory decline. Furthermore, as a group, naMCI have a lower rate of an eventual dementia diagnosis as compared to amnestic subtypes of MCI (aMCI). Unfortunately, studies investigating biomarker profiles of naMCI are scarce. The study objective was to investigate the regional brain glucose metabolism (rBGM) with [18F]FDG-PET and cerebrospinal fluid (CSF) biomarkers in subjects with naMCI as compared to a control group (CG) and aMCI subjects.\ud
\ud
\ud
Methods\ud
Ninety-five patients were included in three different groups: naMCI (N = 32), aMCI (N = 33) and CG (N = 30). Patients underwent brain MRI and [18F]FDG-PET. A subsample (naMCI = 26, aMCI = 28) also had an assessment of amyloid-β, tau, and phosphorylated tau levels in the CSF.\ud
\ud
\ud
Results\ud
Both MCI groups had lower rBGM in relation to the CG in the precuneus. Subjects with naMCI showed decreased right prefrontal metabolism as well as higher levels of CSF amyloid-β relative to aMCI subjects.\ud
\ud
\ud
Conclusion\ud
While amnestic MCI subjects showed a biomarker profile classically related to MCI due to Alzheimer’s disease, naMCI patients illustrated a decrease in both prefrontal hypometabolism and higher CSF amyloid-β levels relative to the aMCI group. These biomarker findings indicate that naMCI is probably a heterogeneous group with similar precuneus hypometabolism compared to aMCI, but additional frontal hypometabolism and less amyloid-β deposition in the brain. Clinical follow-up and reappraisal of biomarkers of the naMCI group is needed to determine the outcome and probable etiological diagnosis.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) numbers 2011/18245-4 and 2009/17398-1 in BrazilCoordination for the Improvement of Higher Education Personnel (CAPES)/Brazi
Brain metabolism and cerebrospinal fluid biomarkers profile of non-amnestic mild cognitive impairment in comparison to amnestic mild cognitive impairment and normal older subjects
Abstract\ud
\ud
Introduction\ud
Mild cognitive impairment (MCI) is classically considered a transitional stage between normal aging and dementia. Non-amnestic MCI (naMCI) patients, however, typically demonstrate cognitive deficits other than memory decline. Furthermore, as a group, naMCI have a lower rate of an eventual dementia diagnosis as compared to amnestic subtypes of MCI (aMCI). Unfortunately, studies investigating biomarker profiles of naMCI are scarce. The study objective was to investigate the regional brain glucose metabolism (rBGM) with [18F]FDG-PET and cerebrospinal fluid (CSF) biomarkers in subjects with naMCI as compared to a control group (CG) and aMCI subjects.\ud
\ud
\ud
Methods\ud
Ninety-five patients were included in three different groups: naMCI (N = 32), aMCI (N = 33) and CG (N = 30). Patients underwent brain MRI and [18F]FDG-PET. A subsample (naMCI = 26, aMCI = 28) also had an assessment of amyloid-β, tau, and phosphorylated tau levels in the CSF.\ud
\ud
\ud
Results\ud
Both MCI groups had lower rBGM in relation to the CG in the precuneus. Subjects with naMCI showed decreased right prefrontal metabolism as well as higher levels of CSF amyloid-β relative to aMCI subjects.\ud
\ud
\ud
Conclusion\ud
While amnestic MCI subjects showed a biomarker profile classically related to MCI due to Alzheimer’s disease, naMCI patients illustrated a decrease in both prefrontal hypometabolism and higher CSF amyloid-β levels relative to the aMCI group. These biomarker findings indicate that naMCI is probably a heterogeneous group with similar precuneus hypometabolism compared to aMCI, but additional frontal hypometabolism and less amyloid-β deposition in the brain. Clinical follow-up and reappraisal of biomarkers of the naMCI group is needed to determine the outcome and probable etiological diagnosis.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) numbers 2011/18245-4 and 2009/17398-1 in BrazilCoordination for the Improvement of Higher Education Personnel (CAPES)/Brazi
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