Sympathetic skin responses from frontal region in migraine headache: a pilot study.

Frontal sympathetic skin responses (F-SSRs) were recorded to investigate sympathetic nervous system activity in migraine headache (MH). Thirty-five patients with unilateral MH and 10 healthy volunteers were studied by evoking bilateral F-SSRs with electrical stimulation of the median nerve in attack, post-attack and interictal periods. The mean latencies were longer and the maximum amplitudes were smaller on the symptomatic side compared with the asymptomatic side (P < 0.05 for both amplitude and latency) in attack and in interictal periods. In five patients, F-SSRs were absent bilaterally, in four patients the responses were absent only on the symptomatic side during the attack period. In the post-attack period, F-SSRs on the symptomatic side had higher amplitudes and shorter latencies compared with the asymptomatic side (P < 0.01 for both amplitude and latency). There is an asymmetric sympathetic hypofunction on the symptomatic side in attack and interictal periods, whereas there is a hyperfunction in the post-attack period.

Monitoring vaccination coverage in Istanbul using the lot quality assurance sampling and geographic information system.

The quality of vaccination services provided for children aged 12-23 months was determined in different districts of Istanbul, Turkey. Quality was assessed through a lot quality assurance sampling method, using data extracted from interviews conducted in 2001 with the mothers or carers of the children. Concurrently, geographic information system technology was used for integrated evaluation of the data from different lots and for presentation of the results as thematic maps. The results of this study helped to identify districts of the city in which vaccination services were below the expected level of quality and where an unacceptable number of children were not being fully vaccinated. Subsequent to this study, actions were taken by the agencies responsible to improve the coverage and quality of the vaccination services in these districts of Istanbul.

Use of a geographic information system in an epidemiological study of measles in Istanbul.

A geographic information system was used in an epidemiological study of measles in Istanbul, Turkey. The aim was to obtain more reliable results and to increase the facilities for spatial monitoring in epidemiological studies. The Gaziosmanpasa district of Istanbul was selected as it experiences the highest level of migration, and currently has the highest population growth rate of the city's districts. The epidemic distribution of measles was investigated on the basis of examination of 320 children. The number, geographical distribution, complications and time of measles outbreaks were analysed and represented in thematic maps (a small selection is shown in this paper). The results were evaluated and, in view of these results, new vaccination plans were arranged.

Pre-focused lead titanate > 25 MHz single-element transducers from hollow spheres.

Miniature lead titanate (PT) hollow spheres with diameters in the 1 to 10 mm range and wall thicknesses of 20 to 120 microns have been fabricated. Shell sections were used as components of pre-focused transducers. Spheres are produced using a new sacrificial core technique that produces hundreds of spheres with a more uniform wall thickness than those produced by earlier methods. Shells produced from these spheres were found to have a wall thickness variation of about 10%. Despite this variation, bulk properties were estimated from capacitance and impedance data. Shells tested in this work had dielectric constants (1 kHz) near 280 with loss factor of < 2% and d33 values of 68 pC/N. Thickness coupling coefficients averaged 0.51 with mechanical quality factors of < 15. A transducer fabricated from these sections of spheres had a round-trip insertion loss of -20.1 dB at the center frequency of 39.8 MHz and a 6 dB bandwidth of 33%.