445 research outputs found
An investigation into the pathogenesis of vulvo-vaginal candidosis
OBJECTIVE: To monitor yeasts isolated from women during and between episodes of recurrent
vulvo-vaginal candidosis (VVC) to determine whether vaginal relapse or re-infection occurred.
METHODS:Women presenting at the genitourinary medicine clinic with signs and symptoms of VVC
were recruited to the study (n = 121). A vaginal washing, high vaginal swab (HVS) and rectal swab
were taken and the women treated with a single 500 mg clotrimazole pessary.Women were asked to
re-attend after 1, 4, and 12 weeks, or when the VVC recurred, when vaginal washings and HVS were
repeated. Candida isolates recovered were strain typed using the Ca3 probe and their similarity
assessed. Antifungal susceptibility to fluconazole and clotrimazole were determined.
RESULTS: Of the women recruited, 47 completed the study, either returning for four visits or suffering
a recurrence during the study period. Of the 22 women who experienced recurrence, the
same strain was responsible for the initial and recurrent episode in 17 women. For the remaining
five women, four had strain replacement and one had a change of species. None of the isolates
recovered from the women demonstrated resistance to either clotrimazole or fluconazole.
CONCLUSIONS: Our findings support the theory of vaginal relapse and thus may support the use
of more prolonged courses of antifungal therapy initially to increase the chances of eradication of
the yeast
Multidimensional relativistic MHD simulations of Pulsar Wind Nebulae: dynamics and emission
Pulsar Wind Nebulae, and the Crab nebula in particular, are the best cosmic
laboratories to investigate the dynamics of magnetized relativistic outflows
and particle acceleration up to PeV energies. Multidimensional MHD modeling by
means of numerical simulations has been very successful at reproducing, to the
very finest details, the innermost structure of these synchrotron emitting
nebulae, as observed in the X-rays. Therefore, the comparison between the
simulated source and observations can be used as a powerful diagnostic tool to
probe the physical conditions in pulsar winds, like their composition,
magnetization, and degree of anisotropy. However, in spite of the wealth of
observations and of the accuracy of current MHD models, the precise mechanisms
for magnetic field dissipation and for the acceleration of the non-thermal
emitting particles are mysteries still puzzling theorists to date. Here we
review the methodologies of the computational approach to the modeling of
Pulsar Wind Nebulae, discussing the most relevant results and the recent
progresses achieved in this fascinating field of high-energy astrophysics.Comment: 29 pages review, preliminary version. To appear in the book
"Modelling Nebulae" edited by D. Torres for Springer, based on the invited
contributions to the workshop held in Sant Cugat (Barcelona), June 14-17,
201
Estudo comparativo do desempenho de três sistemas de colheita mecânica de azeitona
Ao longo de três anos, foi realizado trabalho experimental em olivais com densidades de plantação compreendidas entre 100 e 150 árvores por hectare, utilizando três sistemas de colheita mecânica de azeitona, que permitiram obter resultados de capacidade de trabalho (árvores por hora).
Nos três sistemas, para o destaque dos frutos foi usado o mesmo vibrador de troncos. A diferença está na recolha dos frutos derrubados: no sistema (A) foi realizada manualmente; no sistema (B) foi efectuada com um enrolador de panos montado em tractor; no sistema (C) utilizou-se um apara-frutos.
Os resultados obtidos nos ensaios de campo, permitem (1) apontar as limitações de cada um dos sistemas e (2) sendo conhecida a capacidade de trabalho do sistema que recolhe manualmente a azeitona, estimar para os mesmos olivais e condições de trabalho, os valores de capacidade de trabalho dos sistemas que recolhem a azeitona mecanicamente
Influência da vibração ao tronco ou às pernada na capacidade de trabalho e nos custos da colheita mecânica de azeitona
Ensaios de campo realizados em Trás-os-Montes e no Alentejo mostram como a capacidade de trabalho e custos de operação são afectados quando em consequência da geometria e dimensão das oliveiras há necessidade de efectuar a vibração à pernadas, em vez da mais expedita vibração ao tronco. Os resultados obtidos são úteis para uma tomada de decisão, particularmente por parte dos agricultores possuidores de olivais menos adaptados, que tenham como objectivo adoptar a colheita mecânica
Influence of trunk or bough shaking on the performance and costs of mechanical harvesting of olives
Field trials carried out in Portugal showed the penalty to be paid, both in terms of work rate and costs, whenever, due to tree geometry and size, trees had to be bough shaked rather than the normal trunk shaking. If an olive orchard with trees requiring two bough shakings could be adapted to an entirely trunk shaking orchard, simulation shows an increment between 9% and 33% in the work rate at harvesting and a reduction between 4% and 22% in harvesting cost per kilogram of olive, assuming a 4000 trees size orchard. The data collected is regarded to be very useful for decision support, particularly for those farmers owning less adapted olive orchards, aiming to adopt mechanized harvesting
Magnetic fields in supernova remnants and pulsar-wind nebulae
We review the observations of supernova remnants (SNRs) and pulsar-wind
nebulae (PWNe) that give information on the strength and orientation of
magnetic fields. Radio polarimetry gives the degree of order of magnetic
fields, and the orientation of the ordered component. Many young shell
supernova remnants show evidence for synchrotron X-ray emission. The spatial
analysis of this emission suggests that magnetic fields are amplified by one to
two orders of magnitude in strong shocks. Detection of several remnants in TeV
gamma rays implies a lower limit on the magnetic-field strength (or a
measurement, if the emission process is inverse-Compton upscattering of cosmic
microwave background photons). Upper limits to GeV emission similarly provide
lower limits on magnetic-field strengths. In the historical shell remnants,
lower limits on B range from 25 to 1000 microGauss. Two remnants show
variability of synchrotron X-ray emission with a timescale of years. If this
timescale is the electron-acceleration or radiative loss timescale, magnetic
fields of order 1 mG are also implied. In pulsar-wind nebulae, equipartition
arguments and dynamical modeling can be used to infer magnetic-field strengths
anywhere from about 5 microGauss to 1 mG. Polarized fractions are considerably
higher than in SNRs, ranging to 50 or 60% in some cases; magnetic-field
geometries often suggest a toroidal structure around the pulsar, but this is
not universal. Viewing-angle effects undoubtedly play a role. MHD models of
radio emission in shell SNRs show that different orientations of upstream
magnetic field, and different assumptions about electron acceleration, predict
different radio morphology. In the remnant of SN 1006, such comparisons imply a
magnetic-field orientation connecting the bright limbs, with a non-negligible
gradient of its strength across the remnant.Comment: 20 pages, 24 figures; to be published in SpSciRev. Minor wording
change in Abstrac
Mechanical harvesting of 400 trees per hectare olive orchards based on a rolling canvas prototype
Towards higher densities of trees per hectare different alternatives are required 10 collect olives harvested by trunk shakers. This paper puts forward a revised concept of the trailed can with a rolling canvas system. The equipment consists of a 6m lung box welded 10 a wheeled chassis with a rolling canvas system placed over its full length
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