529 research outputs found
A relação entre parâmetros fisiológicos, desempenho desportivo e possibilidade de despiste de patologias através de testes realizados durante o nado
O objetivo do estudo foi compreender a resposta fisiológica de nadadores imediatamente abaixo e acima da velocidade no estado estacionário máximo de lactato (vEEML) e observar a relação de parâmetros da cinética do consumo oxigénio (V̇O2) com o desempenho na natação. Nadadores de competição (N = 12) completaram 400 m e 800 m máximos para caracterização do desempenho e determinação da velocidade aeróbia máxima (VAM). Um teste progressivo e a determinação direta do EEML tiveram lugar em diferentes dias assim como transições de 500 m para determinação da cinética do V̇O2. Verificou-se que a vEEML representa o limite de estabilidade de variáveis fisiológicas e delimita a intensidade de exercício relativamente ao surgir de desequilíbrios e caminho para o acumular de fadiga e exaustão. A cinética do V̇O2 da fase primária revelou-se associada com o desempenho, podendo igualmente constituir-se como uma ferramenta útil no despiste de patologias detectáveis durante o exercício quer em indivíduos regularmente treinados, quer em indivíduos que treinam de forma recreativa
Pine wilt disease: detection of the pinewood nematode (Bursaphelenchus xylophilus) as a tool for a pine breeding programme
The pinewood nematode (PWN), Bursaphelenchus xylophilus, is a serious quarantine pest first detected in Portugal and Europe in 1999. It
is the causal agent of pine wilt disease (PWD). A resistance breeding programme has been initiated to contribute to control the evolution
of the disease. Five hundred and four adult maritime pine, Pinus pinaster, trees were phenotypically selected as candidate trees for this programme
from an area affected by PWD. To identify tolerance to the nematode, the selected trees were monitored monthly. Over the course
of 1 year, 57 candidate trees died and were tested for the presence/absence of the PWN. As accuracy of detection is of major importance,
an ITS-PCR-based method applied directly to wood from adult maritime pine trees was tested and compared with a standard morphological
identification method. The results showed that the use of PCR to detect the pathogen provided more rapid and accurate results in comparison
with the standard morphological identification. Thus, this method is suitable to be used in the survey of the breeding population
for resistance/tolerance to PWD
Diagnóstico de shunt portosistémico mediante gammagrafía per-rectal y trans-esplénica en el perro
La gammagrafía permite el diagnóstico de shunt portosistémico de manera rápida y no invasiva mediante la técnica per-rectal o la trans-esplénica. En este estudio se describen y comparan los resultados obtenidos en el perro mediante las dos técnicas. La trans-esplénica se considera más adecuada debio a la obtención de imágenes de mayor calidad.
The effect of handlebar height and bicycle frame length on muscular activity during cycling: a pilot study
The cycling literature is filled with reports of electromyography (EMG) analyses for a better understanding of muscle function during cycling. This research is not just limited to performance, as the cyclist’s goal may be rehabilitation, recreation, or competition, so a bicycle that meets the rider’s needs is essential for a more efficient muscular activity. Therefore, the purpose of this study was to understand the contribution of the activity of each of the following muscles: TD (trapezius descending), LD (latissimus dorsi), GM (gluteus maximus), and AD (anterior deltoid) in response to different bicycle-rider systems (handlebar height; bicycle frame length) and intensities in a bicycle equipped with a potentiometer. Surface EMG signals from muscles on the right side of the body were measured. A general linear model test was used to analyze the differences between muscle activation in the test conditions. Effect sizes were calculated using a partial Eta2 (η 2 ). The level of significance was set at 0.05. Muscle activation of different muscles differs, depending on the cycling condition (Pillai’s trace = 2.487; F (36.69) = 9.300; p < 0.001. η 2 = 0.958), mostly during low intensities. In high intensities, one specific pattern emerges, with a greater contribution of GM and TD and weaker participation of LD and AD, enhancing the cycling power output.info:eu-repo/semantics/publishedVersio
The distance-time relationship and oxygen uptake kinetics in swimming
Trabalho apresentado no 19th Annual Congress of the European College of Sport Science, 2-5 julho, Amesterdão, Holand
Kinematic parameters and oxygen uptake kinetics during sub-maximal exercise in swimming
Trabalho apresentado no 19 th Annual Congress of the European College of Sport Science, 2-5 julho 2014, Amesterdão, Holand
The AMIGA sample of isolated galaxies. V. Quantification of the isolation
The AMIGA project aims to build a well defined and statistically significant
reference sample of isolated galaxies in order to estimate the environmental
effects on the formation and evolution of galaxies. The goal of this paper is
to provide a measure of the environment of the isolated galaxies in the AMIGA
sample, quantifying the influence of the candidate neighbours identified in our
previous work and their potential effects on the evolution of the primary
galaxies. Here we provide a quantification of the isolation degree of the
galaxies in this sample. Our starting sample is the Catalogue of Isolated
Galaxies (CIG). We used two parameters to estimate the influence exerted by the
neighbour galaxies on the CIG galaxy: the local number density of neighbour
galaxies and the tidal strength affecting the CIG galaxy. We show that both
parameters together provide a comprehensive picture of the environment. For
comparison, those parameters have also been derived for galaxies in denser
environments such as triplets, groups and clusters. The CIG galaxies show a
continuous spectrum of isolation, as quantified by the two parameters, from
very isolated to interacting. The fraction of CIG galaxies whose properties are
expected to be influenced by the environment is however low (159 out of 950
galaxies). The isolated parameters derived for the comparsion samples gave
higher values than for the CIG and we found clear differences for the average
values of the 4 samples considered, proving the sensitivity of these
parameters. The environment of the galaxies in the CIG has been characterised,
using two complementary parameters quantifying the isolation degree, the local
number density of the neighbour galaxies and the tidal forces affecting the
isolated galaxies. (Abridged)Comment: 10 pages, 12 figures, proposed for acceptance A&
Disentangling the circumnuclear environs of Centaurus A: Gaseous Spiral Arms in a Giant Elliptical Galaxy
We report the existence of spiral arms in the recently formed gaseous and
dusty disk of the closest giant elliptical, NGC 5128 (Centaurus A), using high
resolution 12CO(2-1) observations of the central 3 arcmin (3 kpc) obtained with
the Submillimeter Array (SMA). This provides evidence that spiral-like features
can develop within ellipticals if enough cold gas exists. We elucidate the
distribution and kinematics of the molecular gas in this region with a
resolution of 4.4 x 1.9 (80 pc x 40 pc). The spiral arms extend from the
circumnuclear gas at a radius of 200 pc to at least 1 kiloparsec. The general
properties of the arms are similar to those in spiral galaxies: they are
trailing, the width is \sim 500 \pm 200 pc, and the pitch angle is 20 degrees.
From independent estimates of the time when the HI-rich galaxy merger occurred,
we infer that the formation of spiral arms happened on a time scale of less
than \sim10^8 yr. The formation of spiral arms increases the gas density and
thus the star formation efficiency in the early stages of the formation of a
disk.Comment: 13 pages, 4 Figures. Accepted for publication in ApJ
A framework for the analysis of refugee self-reliance and humanitarian action in urban markets
Disentangling the circumnuclear environs of Centaurus A: II. On the nature of the broad absorption line
We report on atomic gas (HI) and molecular gas (as traced by CO(2-1))
redshifted absorption features toward the nuclear regions of the closest
powerful radio galaxy, Centaurus A (NGC 5128). Our HI observations using the
Very Long Baseline Array allow us to discern with unprecedented sub-parsec
resolution HI absorption profiles toward different positions along the 21 cm
continuum jet emission in the inner 0."3 (or 5.4 pc). In addition, our CO(2-1)
data obtained with the Submillimeter Array probe the bulk of the absorbing
molecular gas with little contamination by emission, not possible with previous
CO single-dish observations. We shed light with these data on the physical
properties of the gas in the line of sight, emphasizing the still open debate
about the nature of the gas that produces the broad absorption line (~55 km/s).
First, the broad H I line is more prominent toward the central and brightest 21
cm continuum component than toward a region along the jet at a distance ~ 20
mas (or 0.4 pc) further from it. This suggests that the broad absorption line
arises from gas located close to the nucleus, rather than from diffuse and more
distant gas. Second, the different velocity components detected in the CO(2-1)
absorption spectrum match well other molecular lines, such as those of
HCO+(1-0), except the broad absorption line that is detected in HCO+(1-0) (and
most likely related to that of the H I). Dissociation of molecular hydrogen due
to the AGN seems to be efficient at distances <= 10 pc, which might contribute
to the depth of the broad H I and molecular lines.Comment: 17 pages, 9 figures, accepted for publication in Ap
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