This paper will describe the rationale and findings from a multinational study of online uses and gratifications conducted in the United States, Korea, and the Netherlands in spring 2003. A survey research method of study was conducted using a questionnaire developed in three languages and was presented to approximately 400 respondents in each country via the Web. Web uses and gratifications were analyzed cross-nationally in a comparative fashion and focused on the perceived involvement in different types of on-line communities. Findings indicate that demographic characteristics, cultural values, and Internet connection type emerged as critical factors that explain why the same technology is adopted differently. The analyses identified seven major gratifications sought by users in each country: social support, surveillance & advice, learning, entertainment, escape, fame & aesthetic, and respect. Although the Internet is a global medium, in general, web use is more local and regional. Evidence of media use and cultural values reported by country and online community supports the hypothesis of a technological convergence between societies, not a cultural convergence.
To validate the model-based 3D dose calculation performed by theCOMPASS system, and to evaluate the use of the combination ofmodel-based and measurement-based 3D dose determination forclinical QA purposes.
The performance of neural electrodes in physiological fluid, especially in chronic use, is critical for the success of functional electrical stimulation devices. Tips of the Utah electrode arrays (UEAs) were coated with sputtered iridium oxide film (SIROF) and activated iridium oxide film (AIROF) to study the degradation during charge injection consistent with functional electrical stimulation (FES). The arrays were subjected to continuous biphasic, cathodal first, charge balanced (with equal cathodal and anodal pulse widths) current pulses for 7 h (>1 million pulses) at a frequency of 50 Hz. The amplitude and width of the current pulses were varied to determine the damage threshold of the coatings. Degradation was characterized by scanning electron microscopy, inductively coupled plasma mass spectrometry, electrochemical impedance spectroscopy and cyclic voltammetry. The injected charge and charge density per phase were found to play synergistic role in damaging the electrodes. The damage threshold for SIROF coated electrode tips of the UEA was between 60 nC with a charge density of 1.9 mC/cm2 per phase and 80 nC with a charge density of 1.0 mC/cm2 per phase. While for AIROF coated electrode tips, the threshold was between 40 nC with a charge density of 0.9 mC/cm2 per phase and 50 nC with a charge density of 0.5 mC/cm2 per phase. Compared to AIROF, SIROF showed higher damage threshold and therefore is highly recommended to be used as a stimulation material.
