Integrated ultra-thin-film gas sensors

The fabrication and performance of an ultra-thin-film integrated gas sensor for detecting impurities in semiconductor process gases are described. Detector reponses are based on gas-induced resistance changes in an ultra-thin Ti-P film mounted on a thin dielectric window supported by a silicon rim. The window temperature can be shifted several hundred degrees Celsius in less than one second. Gas-induced resistance changes are composed of thermal and Chemical components. The gas concentration and its thermal conductivity determine the thermal contribution, whereas the chemical interactions between the gas and the sensor surface create a superimposed change of resistance, which can be observed when the detector is operated at constant temperature. Pretreament of the as-deposited Ti-Pt thin films under controlled environmental conditions allows tailoring of the electrical, sensing, and microstructural characteristics of the films. One such pretreatment scheme allows the creation of films that, when operated at 150 [deg]C, respond chemically to O2 from 1000 torr down to the 10-7 torr level without any evidence of hysteresis or long-term drift over hundreds of cycles of temperature and gas. There is no chemical response to CF4, which allows detection of sub-ppm levels of O2 in CF4. Temperature-programmed desorption (TPD) of O2 is shown to be a control requirement for dynamic sensing.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/31592/1/0000521.pd

Use of multicriteria decision analysis for assessing the benefit and risk of over-the-counter analgesics

Objectives To test the ability of a multicriteria decision analysis (MCDA) model to incorporate disparate data sources of varying quality along with clinical judgement in a benefit–risk assessment of six well-known pain-relief drugs. Methods Six over-the-counter (OTC) analgesics were evaluated against three favourable effects and eight unfavourable effects by seven experts who specialise in the relief of pain, two in a 2-day facilitated workshop whose input data and judgements were later peer-reviewed by five additional experts. Key findings Ibuprofen salts and solubilised emerged with the best benefit–risk profile, followed by naproxen, ibuprofen acid, diclofenac, paracetamol and aspirin. Conclusions Multicriteria decision analysis enabled participants to evaluate the OTC analgesics against a range of favourable and unfavourable effects in a group setting that enabled all issues to be openly aired and debated. The model was easily communicated and understood by the peer reviewers, so the model should be comprehensible to physicians, pharmacists and other health professionals

Use of multicriteria decision analysis for assessing the benefit and risk of over-the-counter analgesics

Objectives : To test the ability of a multi-criteria decision analysis (MCDA) model to incorporate disparate data sources of varying quality along with clinical judgement in a benefit-risk assessment of six well-known pain-relief drugs. Methods: Six OTC analgesics were evaluated against three favourable effects and eight unfavourable effects by seven experts who specialise in the relief of pain, two in a two-day facilitated workshop whose input data and judgements were later peer-reviewed by five additional experts. Key findings: Ibuprofen salts & solubilised emerged with the best benefit-risk profile, followed by naproxen, ibuprofen acid, diclofenac, paracetamol, and aspirin. Conclusions: MCDA enabled participants to evaluate the OTC analgesics against a range of favourable and unfavourable effects in a group setting that enabled all issues to be openly aired and debated. The model was easily communicated and understood by the peer reviewers, so the model should be comprehensible to physicians, pharmacists, and other health professional