4,476 research outputs found
Alimentação de Liposarcus anisitsi e Potamorhina squamoralevis, peixes abundantes na BaÃa Tuiuiú, Pantanal, Mato Grosso do Sul, Brasil.
Os grandes sistemas fluviais da América do Sul abrigam uma grande diversidade de espécies de peixes, que obtém o alimento nas mais diversas fontes. Este trabalho visou identificar e analisar a composição da dieta de Liposarcus anisitsi e Potamorhina squamoralevis, espécies abundantes na baÃa Tuiuiú, Pantanal, Mato Grosso do Sul. Foram realizadas coletas bimestrais, durante três anos, na baÃa Tuiuiú, meandro abandonado do rio Paraguai. Dos exemplares coletados foram retirados os tratos digestivos e o conteúdo foi homogeneizado e diluÃdo diversas vezes para facilitar a leitura e identificação dos itens alimentares que foi efetuada sob microscópio. As duas espécies apresentaram o detrito/sedimento como principal item alimentar. Além dos detritos, L. anisitsi ingeriu quantidades expressivas de restos de vegetais e algas. P. squamoralevis ingeriu quantidades significativas de algas e restos de vegetais são menos importantes na sua dieta. Também foram ingeridos outros itens, em menor proporção. Na baÃa Tuiuiú, P. squamoralevis e L. anisitsi podem ser classificados como espécies especializadas, uma vez que se alimentam principalmente de detrito/sedimento, com alguma tendência a generalistas, já que podem se alimentar também de outros itens alimentares associados a detritos. As espécies utilizam diferentes micro-hábitats na captura do alimento o que possibilita a sua coexistência. Devido à sua abundância e frequência de ocorrência, os peixes detritÃvoros constituem a base da cadeia alimentar aquática na baÃa Tuiuiú. The major river systems of South America have a great diversity of fish species, which feed on a great diversity of food sources. This study aimed to identify and analyze the composition of the feeding of Liposarcus anisitsi and Potamorhina squamoralevis, abundants in the Tuiuiú bay, Pantanal, Mato Grosso do Sul State. Samples were collected bimonthly during three years in the Tuiuiú bay, an oxbow lake the Paraguay river. From the specimens were taken the digestive tracts and the contents were homogenized and diluted several times to facilitate the reading and identification of food items that was performed under microscope. In both fish species, the detritus / sediment were the main food item. L. anisitsi ingested large amounts of plant debris and algae. P. squamoralevis ingested significant amounts of algae; plant remains are less important in the diet of this species. Other items were also eaten in smaller proportions. In the Tuiuiú bay, P. squamoralevis and L. anisitsi can be classified as specialized species, since they feed mainly on detritus / sediment, with some degree to generalism, since it can feed also on other food items. L. anisitsi and P. squamoralevis use different microhabitats to capture food which allow them to coexist. Due to its abundance and frequency of occurrence, detritus feeding fishes are the basis of the aquatic food chain in the Tuiuiú bay
third caesarean section in patient with myasthenia gravis
Abstract Myasthenia gravis (MG) is an autoimmune neuromuscular disease, characterised by muscle weakness and fatigability of the voluntary muscles, it affects young women in the second and third decade of life. We report a case of 30 years old multigravida woman with myasthenia gravis submitted to third iterative caesarean section with no adverse neonatal and maternal outcome. The course myathenia is highly variable and unpredictable during gestation and can change in subsequent pregnancies. Delivery specially, through caesarean section is very stressful and may cause severe myasthenic crisis. Although pregnancy and delivery represent particular events, that require more attention in these patients, they are not associated, in most cases, with higher risks of complications compared to normal pregnancy, delivery and postpartum period. According our experiences, in the management of myasthenic pregnant woman is necessary cooperation in a multidisciplinary team between obstetricians, neurologist, anaesthetist, and neonatologist for ensure an optimum outcome
Spontaneous creation of Kibble-Zurek solitons in a Bose-Einstein condensate
When a system crosses a second-order phase transition on a finite timescale,
spontaneous symmetry breaking can cause the development of domains with
independent order parameters, which then grow and approach each other creating
boundary defects. This is known as Kibble-Zurek mechanism. Originally
introduced in cosmology, it applies both to classical and quantum phase
transitions, in a wide variety of physical systems. Here we report on the
spontaneous creation of solitons in Bose-Einstein condensates via the
Kibble-Zurek mechanism. We measure the power-law dependence of defects number
with the quench time, and provide a check of the Kibble-Zurek scaling with the
sonic horizon. These results provide a promising test bed for the determination
of critical exponents in Bose-Einstein condensates.Comment: 7 pages, 4 figure
The Gaia-ESO Survey: a quiescent Milky Way with no significant dark/stellar accreted disc
According to our current cosmological model, galaxies like the Milky Way are
expected to experience many mergers over their lifetimes. The most massive of
the merging galaxies will be dragged towards the disc-plane, depositing stars
and dark matter into an accreted disc structure. In this work, we utilize the
chemo-dynamical template developed in Ruchti et al. to hunt for accreted stars.
We apply the template to a sample of 4,675 stars in the third internal data
release from the Gaia-ESO Spectroscopic Survey. We find a significant component
of accreted halo stars, but find no evidence of an accreted disc component.
This suggests that the Milky Way has had a rather quiescent merger history
since its disc formed some 8-10 billion years ago and therefore possesses no
significant dark matter disc.Comment: 15 pages, 11 figures, accepted for publication in MNRA
Influences of Psychological Traits and PROP Taster Status on Familiarity with and Choice of Phenol-Rich Foods and Beverages
Plant phenolics are powerful antioxidants and free radical scavengers that can contribute to the healthy functional properties of plant-based food and beverages. Thus, dietary behaviours rich in plant-based food and beverages are encouraged. However, it is well-known that the bitter taste and other low-appealing sensory properties that characterize vegetables and some other plant-based foods act as an innate barrier for their acceptance. The aim of this study was to investigate the influence of psychological traits and PROP status (the responsiveness to bitter taste of 6-n- propylthiouracil) on the choice of and familiarity with phenol-rich vegetables and beverages varying in recalled level of bitterness and astringency. Study 1 aimed at assessing the variations of the sensory properties of vegetable and coffee/tea items with two check-all-that-apply (CATA) questionnaires (n = 201 and n = 188 individuals, respectively). Study 2 aimed at investigating how sensitivity to punishment, to reward, and to disgust, food neophobia, private body consciousness, alexithymia, and PROP responsiveness affect choice and familiarity with phenol-rich foods (n = 1200 individuals). A Choice Index was calculated for vegetables (CV) and coffee/tea (CC) as a mean of the choices of the more bitter/astringent option of the pairs and four Familiarity Indices were computed for vegetables (FV) and coffee/tea (FC), higher (+) or lower (-) in bitterness and astringency. Subjects higher in food neophobia, sensitivity to punishment or sensitivity to disgust reported significantly lower choice indices than individuals lower in these traits, meaning that they systematically opted for the least bitter/astringent option within the pairs. Familiarity with vegetables was lower in individuals high in sensitivity to punishment, in food neophobia and in alexithymia, irrespective of their sensory properties. The Familiarity Index with coffee/tea characterized by higher bitterness and astringency was lower in individuals high in food neophobia, sensitivity to disgust, and alexithymia. No significant effect of PROP was found on any indices. The proposed approach based on product grouping according to differences in bitterness and astringency allowed the investigation of the role of individual differences in chemosensory perception and of psychological traits as modulators of phenol-rich foods preference and consumption
Photoionized OVI absorbers toward the bright QSO HE 0515-4414
We report on detailed Monte Carlo inversion analysis of five OVI systems from
the spectrum of the bright quasar HE 0515-4414 (z_e = 1.71). The associated
system at z_a = 1.697 with the neutral hydrogen column density N(HI)= 4.4
10^{13} cm^{-2} shows pronounced absorption from highly ionized transitions of
CIII, CIV, NV, OVI, SiIV, and probably SVI. We found that only a power law type
ionizing spectrum (J_nu propto nu^{-1.5}) is consistent with the observed
sample of the line profiles, i.e. the system is definitely intrinsic. The
relative metal abundances give almost the solar pattern and the metallicity of
about 5 times solar. The system originates in a thin shell of the line-of-sight
thickness L <= 16 pc. Two OVI systems at z_a = 1.674 ([C/H] = -1.6) and 1.602
([O/H] = -1.1), arising in intervening halos, have linear sizes of L = 3-14 kpc
and 17 kpc, respectively. Absorption systems at z_a = 1.385 ([C/H] = -0.3, L =
1.7-2.5 kpc) and z_a = 1.667 ([C/H] = -0.5, L = 1 kpc) exhibit characteristics
very similar to that observed in metal-enriched high velocity clouds in the
Milky Way.These systems are probably embedded in extremely metal-poor halos
with [C/H] < -2.4 (z_a = 1.667) and [C/H] < -3.7 (z_a = 1.385). We also found
two additional extremely metal-poor Ly-alpha systems at z_a = 1.500 and 1.681
with, respectively, N(HI) = 1.7 10^{15} and 1.8 10^{15} cm^{-2} and [C/H] <
-4.0 and <-3.0, - an indication that the distribution of metals in the
metagalactic medium is utterly patchy. Our results show that the ionization
states in the analyzed OVI absorbers, ranging from z = 1.4 to 1.7, can be
maintained by photoionization only and that the fraction of the shock-heated
hot gas with temperature T > 10^5 K is negligible in these systems.Comment: 16 pages, including 11 PostScript figures. Accepted for publication
in A&
Measurement of boron and carbon fluxes in cosmic rays with the PAMELA experiment
The propagation of cosmic rays inside our galaxy plays a fundamental role in
shaping their injection spectra into those observed at Earth. One of the best
tools to investigate this issue is the ratio of fluxes for secondary and
primary species. The boron-to-carbon (B/C) ratio, in particular, is a sensitive
probe to investigate propagation mechanisms. This paper presents new
measurements of the absolute fluxes of boron and carbon nuclei, as well as the
B/C ratio, from the PAMELA space experiment. The results span the range 0.44 -
129 GeV/n in kinetic energy for data taken in the period July 2006 - March
2008
Trapped proton fluxes at low Earth orbits measured by the PAMELA experiment
We report an accurate measurement of the geomagnetically trapped proton
fluxes for kinetic energy above > 70 MeV performed by the PAMELA mission at low
Earth orbits (350-610 km). Data were analyzed in the frame of the adiabatic
theory of charged particle motion in the geomagnetic field. Flux properties
were investigated in detail, providing a full characterization of the particle
radiation in the South Atlantic Anomaly region, including locations, energy
spectra and pitch angle distributions. PAMELA results significantly improve the
description of the Earth's radiation environment at low altitudes placing
important constraints on the trapping and interaction processes, and can be
used to validate current trapped particle radiation models.Comment: 22 pages, 5 figure
Geomagnetically trapped, albedo and solar energetic particles: trajectory analysis and flux reconstruction with PAMELA
The PAMELA satellite experiment is providing comprehensive observations of
the interplanetary and magnetospheric radiation in the near-Earth environment.
Thanks to its identification capabilities and the semi-polar orbit, PAMELA is
able to precisely measure the energetic spectra and the angular distributions
of the different cosmic-ray populations over a wide latitude region, including
geomagnetically trapped and albedo particles. Its observations comprise the
solar energetic particle events between solar cycles 23 and 24, and the
geomagnetic cutoff variations during magnetospheric storms. PAMELA's
measurements are supported by an accurate analysis of particle trajectories in
the Earth's magnetosphere based on a realistic geomagnetic field modeling,
which allows the classification of particle populations of different origin and
the investigation of the asymptotic directions of arrival.Comment: Accepted for publication in Advances in Space Research, 2016. 21
pages, 7 figure
CLASH-VLT: Substructure in the galaxy cluster MACS J1206.2-0847 from kinematics of galaxy populations
In the effort to understand the link between the structure of galaxy clusters
and their galaxy populations, we focus on MACSJ1206.2-0847 at z~0.44 and probe
its substructure in the projected phase space through the spectrophotometric
properties of a large number of galaxies from the CLASH-VLT survey. Our
analysis is mainly based on an extensive spectroscopic dataset of 445 member
galaxies, mostly acquired with VIMOS@VLT as part of our ESO Large Programme,
sampling the cluster out to a radius ~2R200 (4 Mpc). We classify 412 galaxies
as passive, with strong Hdelta absorption (red and blue galaxies, and with
emission lines from weak to very strong. A number of tests for substructure
detection are applied to analyze the galaxy distribution in the velocity space,
in 2D space, and in 3D projected phase-space. Studied in its entirety, the
cluster appears as a large-scale relaxed system with a few secondary, minor
overdensities in 2D distribution. We detect no velocity gradients or evidence
of deviations in local mean velocities. The main feature is the WNW-ESE
elongation. The analysis of galaxy populations per spectral class highlights a
more complex scenario. The passive galaxies and red strong Hdelta galaxies
trace the cluster center and the WNW-ESE elongated structure. The red strong
Hdelta galaxies also mark a secondary, dense peak ~2 Mpc at ESE. The emission
line galaxies cluster in several loose structures, mostly outside R200. The
observational scenario agrees with MACS J1206.2-0847 having WNW-ESE as the
direction of the main cluster accretion, traced by passive galaxies and red
strong Hdelta galaxies. The red strong Hdelta galaxies, interpreted as
poststarburst galaxies, date a likely important event 1-2 Gyr before the epoch
of observation. The emission line galaxies trace a secondary, ongoing infall
where groups are accreted along several directions.Comment: A&A accepted, 19 pages, 30 figures, minor language change
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