Counting Immigrants and Expatriates in OECD Countries: A New Perspective

Since the end of the 1990s, issues related to international migration, and more particularly to the international mobility of highly-qualified workers, are receiving increasing attention from policy-makers. This reflects among others the increasing international movements that have been taking place following the fall of the Iron Curtain and in conjunction with the growing globalisation of economic activity. In addition, demographic imbalances between developed and developing countries and large differences in wages have tended to encourage the movements of workers from economies where they are in surplus to those where they are most in need.....

Encuentros, Summer 2004

Encuentros is the newsletter published by the Center for Latino and Latin American Studies Center at Northern Illinois University

SAR characteristics of three types of Contact Flexible Microstrip Applicators for superficial hyperthermia

The Effective Field Sizes (EFS) and the Effective Heating Depths (EDH) of Contact Flexible Microstrip Applicators (CFMA), tuned at a frequency of 434 MHz, were determined on two fat/muscle phantoms. One phantom was box-shaped with a flat top layer of 1 cm thick artificial fat and the other one a tube of which the cross-section was elliptically shaped (25 x 36 cm) having a fat equivalent shell of 1 cm thick. For the muscle material a 6 g/l saline (NaCl) solution was used. On the flat rectangular phantom, the effective field size at 1 cm depth in saline was measured to be 4.7 x 13.5 cm, 17.5 x 17.7 cm and 12.5 x 14.0 cm for the 1H-applicator, the 3H-applicator and the 5H-applicator, respectively. For the 3H-and the 5H-applicator, the Specific absorption rate (SAR) distribution at 1 cm depth showed a single maximum of SAR for a thin bolus, which split into two separate "hot spots' for a thicker bolus. The Effective Heating Depths in the phantom with a flat surface were of the order of that of a plane wave (approximately 1.4 cm), whereas a larger EHD of 2.4 cm was achieved below the 3H-applicator bent to fit the elliptical phantom. Due to the large effective field size and the "flatness' of the SAR distribution, the applicators 3H and 5H are suitable to adequately treat large superficial tumour