No description available.

No description available.

No description available.

No description available.

Medical products of all kinds have to comply with regulations to satisfy the demand for public health and safety. Medicinal products (drugs) were the first medical products to be regulated in most countries and regulations for medical devices - generally derived from drug regulations - followed. This thesis reviews the development of safety regulation for medical devices from its relatively recent introduction in the 1960s to the present day. The emphasis is on the situation in countries of the European Community but events in these countries are placed in a world-wide context. Landmark events in this process - notably the US Medical Device Amendments of 1976 and the EC Medical Device Directive of 1994 - are analysed and compared. An examination of current regulations in the three major markets for medical devices: Europe, Japan and USA, leads to the identification of quality systems, product standards, effectiveness/performance and post-market controls as key factors in modern regulatory approaches. The emergence of these key factors illustrates the movement towards an engineering, rather than a pharmaceutical, approach to regulation and their place in current and emerging regulations world-wide is discussed. Manufacturers have long pressed for uniformity in national regulations to reduce the time and cost involved in obtaining market approval and their case has been largely accepted by the regulatory authorities. Harmonization in Europe has been achieved as part of the Single Market programme. The last decade has seen remarkable progress towards the further harmonizing of national and regional regulations. The outstanding difficulties, notably controversy over the need for "effectiveness" determination and relative roles of clinical and laboratory testing, are discussed and solutions proposed. The prospects for achieving global harmonization are examined and a possible future global system is described.

Acupuncture has had a long and interesting history. However acupuncture still faces challenge from its mechanism explanation. The traditional acupuncture theory may not fully explain electroacupuncture. This study carries out an investigation into electroacupuncture from bioenergy, bioelectricity, and electrotherapy points of view. An experimental and theoretical study of the electrical property of acupoints is conducted. An equivalent model of tissues under electroacupuncture electrical field is developed. In conjunction with this, an improved technique is used in the resistance test to investigate the electrical properties of acupoints, in which the "least-value hunting" method, forcecontrollable probe, and square electrical waveform have been adopted. The currently used apparatus for electroacupuncture is improved by the development of computer-based electroacupuncture instrumentation. On the basis of this development, the methodology of Internet-based remote control and monitoring is introduced in the therapeutic and training process. A standardised and quantified elctroacupuncture is investigated through the implementation of a fuzzy decision making system. The fuzzy controllers are developed and embedded in a PC-based instrumentation system to overcome "accommodation", which occurs during the electroacupuncture process.

No description available.

Ultrasonic cleaning baths are routinely used for cleaning dental and surgical instruments. The importance of efficient cleaning prior to sterilisation is great. Micro-organisms can survive the sterilisation process as debris can act as an insulator. The information available on ultrasonic field distributions in cleaning baths is limited. A thermal technique, employing a thermistor probe coated with an absorbing material measures the temperature rise when the field is switched on compared to no sound temperature. Contour plots of the field of the cleaning bath resulted from point-to-temperature. Contour plots of the field of the cleaning bath resulted from point-to-point measurements. Optical methods were also employed for qualitative measurements of the field. The main optical method used in this study is the Sarvazyan, dye/paper method where dye patterns represent the distribution of the field's cavitation activity at that area. Titanium coated mica was also used for seeding the bath. When the field was switched on, these particles migrated towards the antinodes, the distribution of particles in the field gives qualitative measure for the field. Aluminium surfaces were sonicated and erosion with pitting was evident after 30-60 minutes sonication time. Some plates were examined under an SEM. Cleaning efficiency was directly examined by coating perspex and stainless steel plates with blood. The plates were left to dry for 24 hours then sonicated. Water and Decon-90® detergent gave very similar removal times, with the detergent to achieve cleaning marginally faster compared to water. A disinfectant-detergent was also used, Virkon®. The results with Virkon were disappointing, red cells were caused to lyse up by Virkon and as a result a colloidal mixture was formed. This mixture was not able to be removed ultrasonically, even after an hour or more sonication time. Manual brushing was required in that case. In general all baths tested showed a non-uniform field pattern that can result in insufficient cleaning.

No description available.

No description available.