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In March 1997, an outbreak of Vero cytotoxin-producing Escherichia coli O157 (VTEC) infection occurred amongst holidaymakers returning from Fuerteventura, Canary Islands. For the investigation, a confirmed case was an individual staying in Fuerteventura during March 1997, with either E. coli O157 VTEC isolated in stool, HUS or serological evidence of recent… (More)
Multidrug-resistance and extensive drug-resistance pose a serious threat to tuberculosis management in Portugal. The country has high TB incidence rates in comparison with other European Union countries, with the Lisbon Health Region being one of the most affected. In the present study we have analysed a convenience sample of 3025 Mycobacterium tuberculosis… (More)
Following the introduction of an improved surveillance system for infectious intestinal disease outbreaks in England and Wales, the Public Health Laboratory Service Communicable Disease Surveillance Centre received reports of 26 outbreaks between 1 January 1992 and 31 December 1995 in which there was evidence for waterborne transmission of infection. In… (More)
Neisseria meningitidis capsular switching has been reported in several countries. In order to establish the genetic relationship within group B and C strains expressing subtypes 2a or 2b, and to evaluate whether C to B capsular switching occurred in Portugal, 64 meningococci (56 serogroup C and 8 serogroup B) isolated from invasive meningococcal disease… (More)
Using a continuum model, we obtain qualitative results that imply charge localization around negative curvature disclinations (i.e. rings with more than 6 Carbon atoms) in a graphite sheet. Conversely, it is found that positive curvature disclinations repel charge, independent of its sign.
In this work we study a charged particle in the presence of both a continuous distribution of disclinations and a continuous distribution of edge dislocations in the framework of the geometrical theory of defects. We obtain the self-energy for a single charge both in the internal and external regions of either distribution. For both distributions the result… (More)
In this work we study the Landau levels in the presence of topological defects. We analyze the behavior of electrons moving in a magnetic field in the presence of a continuous distribution of disclinations, a magnetic screw dislocation and a dispiration. We focus on the influence of these topological defects on the spectrum of the electron (or hole) in the… (More)
We deal with scalar field coupled to gravity in five dimensions in warped geometry. We investigate models described by potentials that drive the system to support thick brane solutions that engender internal structure. We find analytical expressions for the brane solutions, and we show that they are all linearly stable.
Olive fruit fly Bactrocera oleae (Rossi) (Diptera: Tephritidae) is a major olive pest in the Mediterranean basin where increasing insecticide resistance has enhanced damage and necessitates more reliance on other control strategies, such as biological control. Provision of floral resources has been reported to improve the effectiveness of natural enemies.… (More)