62 research outputs found
CONSTRAINING THE ANGULAR MOMENTUM EVOLUTION OF V455 ANDROMEDAE
Time-series photometry on the cataclysmic variable V455 Andromedae (hereafter V455 And, HS 2331+3905) reveals a rotation period shorter than the orbital period, implying the presence of a magnetic field. We expect that this magnetic field channels the accreted matter from the disk toward the white dwarf poles, classifying it as an Intermediate Polar. The two polar spinning emission areas are visible in the lightcurves at the rotation period of 67.61970396 ± 0.00000072 s, and its harmonic. Using photometric observations of V455 And obtained from 2007 October to 2015, we derive 3Ï upper limits to the rate of change of the spin harmonic (SH) with time to be dPSH/dt †â7.5 Ă 10â15 s sâ1 employing the OâC method, and â5.4 Ă 10â15 s sâ1 with a direct nonlinear least squares fit. There is no significant detection of a changing spin period for the duration of 2007 Octoberâ2015. The 3Ï upper limit for the rate of change of spin period with time is dPspin/dt †â10.8 Ă 10â15 s sâ1 or â0.34 ÎŒs yrâ1. V455 And underwent a large-amplitude dwarf nova outburst in 2007 September. The pre-outburst data reflect a period 4.8 ± 2.2 ÎŒs longer than the best-fit post-outburst spin period. The angular momentum gained by the white dwarf from matter accreted during outburst and its slight subsequent shrinking should both cause the star to spin slightly faster after the outburst. We estimate that the change in spin period due to the outburst should be 5 ÎŒs, consistent with the empirical determination of 4.8 ± 2.2 ÎŒs (3Ï upper limit of 11.4 ÎŒs)
Determinação de ĂĄcido valprĂłico em soro por cromatografia lĂquida de alta eficiĂȘncia com detector de arranjo de diodos (CLAE-DAD), apĂłs derivatização com brometo de fenacila
Valproic acid (VA) is a drug used to control seizures in several epileptic conditions. In VA pharmacotherapy, therapeutic drug monitoring is recommended to obtain adequate seizure control and avoid toxicity. The aim of this study was to validate a method for the determination of valproic acid in serum, employing high performance liquid chromatography with diode array detection (HPLC-DAD), after derivatization with phenacyl bromide. The calibration curve (y=0.0133x-0.0025) presented good linearity with rÂČ=0.9999. Accuracy (101-115%), intra-assay precision (4.53-8.15%) and inter-assay precision (3.15-6.77%) were acceptable. The quantification limit was 2.0 ”g/mL. The method presented similar results to enzyme immunoassay
EFEITO DE DOSES DE SILĂCIO NA RESISTĂNCIA DO FEIJOEIRO A Spodoptera frugiperda
O presente trabalho objetivou verificar os efeitos das diferentes doses de silĂcio na resistĂȘncia do feijoeiro Ă Spodoptera frugiperda. O delineamento adotado foi inteiramente casualizado com quatro tratamentos e cinco repetiçÔes. Os tratamentos foram representados pelos nĂveis de silĂcio: 0 kg ha-1; 50 kg ha-1; 100 kg ha-1 e 200 kg ha-1, sendo o silicato de potĂĄssio aplicado ao solo com a adubação de plantio. Avaliou-se o desenvolvimento larval, o perĂodo pupal, a biomassa de pupas e a nĂŁo preferĂȘncia alimentar de larvas do primeiro Ănstar. O maior acĂșmulo de silĂcio foliar no feijoeiro foi observado para a dose de 111.1 kg ha-1 de silĂcio. A sobrevivĂȘncia larval de S. frugiperda nĂŁo foi afetada pela adubação de plantas de feijoeiro com silĂcio. PorĂ©m, o perĂodo de desenvolvimento larval aumentou Ă medida que houve o aumento das doses de silĂcio. A nĂŁo preferĂȘncia das lagartas de S. frugiperda aumentou proporcionalmente Ă s doses de silĂcio testadas. A adubação com silicato de potĂĄssio obteve sucesso no controle de S. frugiperda nas dosagens de 100 e 200 kg ha-1, pois mesmo nĂŁo sendo uma cultura acumuladora de silĂcio, obteve uma resposta satisfatĂłria Ă adubação, diminuindo a preferĂȘncia alimentar das lagartas e aumentando seu perĂodo de desenvolvimento larval
Constraining the angular momentum evolution of V455 Andromedae
Time-series photometry on the cataclysmic variable V455 Andromedae (hereafter V455 And, HS 2331+3905) reveals a rotation period shorter than the orbital period, implying the presence of a magnetic field. We expect that this magnetic field channels the accreted matter from the disk toward the white dwarf poles, classifying it as an Intermediate Polar. The two polar spinning emission areas are visible in the lightcurves at the rotation period of 67.61970396 ± 0.00000072 s, and its harmonic. Using photometric observations of V455 And obtained from 2007 October to 2015, we derive 3Ï upper limits to the rate of change of the spin harmonic (SH) with time to be dPSH/dt †â7.5 Ă 10â15 s sâ1 employing the OâC method, and â5.4 Ă 10â15 s sâ1 with a direct nonlinear least squares fit. There is no significant detection of a changing spin period for the duration of 2007 Octoberâ2015. The 3Ï upper limit for the rate of change of spin period with time is dPspin/dt †â10.8 Ă 10â15 s sâ1 or â0.34 ÎŒs yrâ1. V455 And underwent a large-amplitude dwarf nova outburst in 2007 September. The pre-outburst data reflect a period 4.8 ± 2.2 ÎŒs longer than the best-fit post-outburst spin period. The angular momentum gained by the white dwarf from matter accreted during outburst and its slight subsequent shrinking should both cause the star to spin slightly faster after the outburst. We estimate that the change in spin period due to the outburst should be 5 ÎŒs, consistent with the empirical determination of 4.8 ± 2.2 ÎŒs (3Ï upper limit of 11.4 ÎŒs)
Emergence and intensification of dairying in the Caucasus and Eurasian steppes
Archaeological and archaeogenetic evidence points to the Pontic-Caspian steppe zone between the Caucasus and the Black Sea as the crucible from which the earliest steppe pastoralist societies arose and spread, ultimately influencing populations from Europe to Inner Asia. However, little is known about their economic foundations and the factors that may have contributed to their extensive mobility. Here, we investigate dietary proteins within the dental calculus proteomes of 45 individuals spanning the Neolithic to Greco-Roman periods in the Pontic-Caspian Steppe and neighbouring South Caucasus, Oka-Volga-Don and East Urals regions. We find that sheep dairying accompanies the earliest forms of Eneolithic pastoralism in the North Caucasus. During the fourth millennium Bc, Maykop and early Yamnaya populations also focused dairying exclusively on sheep while reserving cattle for traction and other purposes. We observe a breakdown in livestock specialization and an economic diversification of dairy herds coinciding with aridification during the subsequent late Yamnaya and North Caucasus Culture phases, followed by severe climate deterioration during the Catacomb and Lola periods. The need for additional pastures to support these herds may have driven the heightened mobility of the Middle and Late Bronze Age periods. Following a hiatus of more than 500 years, the North Caucasian steppe was repopulated by Early Iron Age societies with a broad mobile dairy economy, including a new focus on horse milking.Peer reviewe
Emergence and intensification of dairying in the Caucasus and Eurasian steppes
Archaeological and archaeogenetic evidence points to the Pontic-Caspian steppe zone between the Caucasus and the Black Sea as the crucible from which the earliest steppe pastoralist societies arose and spread, ultimately influencing populations from Europe to Inner Asia. However, little is known about their economic foundations and the factors that may have contributed to their extensive mobility. Here, we investigate dietary proteins within the dental calculus proteomes of 45 individuals spanning the Neolithic to Greco-Roman periods in the Pontic-Caspian Steppe and neighbouring South Caucasus, Oka-Volga-Don and East Urals regions. We find that sheep dairying accompanies the earliest forms of Eneolithic pastoralism in the North Caucasus. During the fourth millennium Bc, Maykop and early Yamnaya populations also focused dairying exclusively on sheep while reserving cattle for traction and other purposes. We observe a breakdown in livestock specialization and an economic diversification of dairy herds coinciding with aridification during the subsequent late Yamnaya and North Caucasus Culture phases, followed by severe climate deterioration during the Catacomb and Lola periods. The need for additional pastures to support these herds may have driven the heightened mobility of the Middle and Late Bronze Age periods. Following a hiatus of more than 500 years, the North Caucasian steppe was repopulated by Early Iron Age societies with a broad mobile dairy economy, including a new focus on horse milking.Peer reviewe
Abscesso hepĂĄtico por Tuberculose em paciente com HIV: um relato de caso / Liver abscess by Tuberculosis IN HIV patient: a case report
A tuberculose Ă© uma doença infectocontagiosa causada pelo Mycobacterium tuberculosis, comum em paĂses em desenvolvimento. Os acomentimentos pulmonares sĂŁo as principais manifestaçÔes da doença, embora existam, tambĂ©m, manifestaçÔes extrapulmonares, as quais sĂŁo mais comuns em pacientes imunocomprometidos, a exemplo dos pacientes coinfectados com o HIV. O abscesso hepĂĄtico Ă© a forma menos comum de lesĂŁo. Entretanto, quando analisadas as taxas de mortalidade e os resultados dos tratamentos, Ă© uma das manifestaçÔes extrapulmonares com pior prognĂłstico. O caso relatado segue com o diagnĂłstico atravĂ©s dos sinais e sintomas clĂnicos, alĂ©m da realização dos exames laboratoriais e de imagem, a fim de diagnosticar e indicar os tratamentos cirĂșrgico e medicamentoso para tratar a infecção e sua consequente manifestação
AnĂĄlise da qualidade sanitĂĄria da areia das praias de Santos, litoral do estado de SĂŁo Paulo
The Eighteenth Data Release of the Sloan Digital Sky Surveys: Targeting and First Spectra from SDSS-V
The eighteenth data release of the Sloan Digital Sky Surveys (SDSS) is the
first one for SDSS-V, the fifth generation of the survey. SDSS-V comprises
three primary scientific programs, or "Mappers": Milky Way Mapper (MWM), Black
Hole Mapper (BHM), and Local Volume Mapper (LVM). This data release contains
extensive targeting information for the two multi-object spectroscopy programs
(MWM and BHM), including input catalogs and selection functions for their
numerous scientific objectives. We describe the production of the targeting
databases and their calibration- and scientifically-focused components. DR18
also includes ~25,000 new SDSS spectra and supplemental information for X-ray
sources identified by eROSITA in its eFEDS field. We present updates to some of
the SDSS software pipelines and preview changes anticipated for DR19. We also
describe three value-added catalogs (VACs) based on SDSS-IV data that have been
published since DR17, and one VAC based on the SDSS-V data in the eFEDS field.Comment: Accepted to ApJ
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