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Ultrasound is increasingly in demand as a medical imaging tool and can be particularly beneficial in the field of intracardiac echocardiography (ICE). However, many challenges remain in the development of a 3D ultrasound imaging system. We have designed and fabricated a quad-ring capacitive micromachined ultrasound transducer (CMUT) for real-time, volumetric medical imaging. Each CMUT array is composed of four concentric, independent ring arrays, each operating at a different frequency, with 128 elements per ring. In this project, one ring will be used for imaging. A large (5mm diameter) lumen is available for delivering other devices, including high intensity focused ultrasound transducers for therapeutic applications or optical fibers for photoacoustic imaging. We address several challenges in developing a 3D imaging system. Through wafer vias are incorporated in the fabrication process for producing 2D CMUT arrays. Device integration with electronics is achieved through solder bumping the arrays, designing a flexible PCB, and flip chip bonding CMUT and ASICs to the flexible substrate. Finally, we describe a method for integrating the flex assembly into a catheter shaft. The package, once assembled, will be used for in-vivo open chest experiments.

U.S. chemical plants currently have potentially catastrophic vulnerabilities as terrorist targets. The possible consequences of these vulnerabilities echo from the tragedies of the Bhopal incident in 1984 to the terrorist attacks on 11 September 2001 and, most recently, Hurricanes Katrina and Rita. Findings from a 2004 nationwide participatory research study of 125 local union leaders at sites with very large volumes of highly hazardous chemicals suggest that voluntary efforts to achieve chemical plant security are not succeeding. Study respondents reported that companies had only infrequently taken actions that are most effective in preventing or in preparing to respond to a terrorist threat. In addition, companies reportedly often failed to involve key stakeholders, including workers, local unions, and the surrounding communities, in these efforts. The environmental health community thus has an opportunity to play a key role in advocating for and supporting improvements in prevention of and preparation for terrorist attacks. Policy-level recommendations to redress chemical site vulnerabilities and the related ongoing threats to the nation's security are as follows: a) specify detailed requirements for chemical site assessment and security ; b) mandate audit inspections supported by significant penalties for cases of noncompliance ; c) require progress toward achieving inherently safer processes, including the minimizing of storage of highly hazardous chemicals ; d) examine and require additional effective actions in prevention, emergency preparedness, and response and remediation ; e) mandate and fund the upgrading of emergency communication systems ; and f) involve workers and community members in plan creation and equip and prepare them to prevent and respond effectively to an incident.

This paper discusses sampling techniques for archaeological survey that are directed toward evaluating the properties of surface artifact distributions. The sampling techniques we experimented with consist of a multi-scale sampling plot developed in plant ecology and the use of a nested-intensity survey design. We present results from the initial application of these methods. The sampling technique we borrowed from plant ecology is the Modified-Whittaker multiscale sampling plot, which gathers observations at the spatial scales of 1 sq m, 10 sq m, 100 sq m, and 1000 sq m. Nested-intensity surveys gather observations on the same sample units at multiple resolutions. We compare the results of a closely-spaced walking survey, a crawling survey, and a test excavation to a depth of 10 cm. These techniques were applied to ten 20 × 50 m survey plots distributed over an area of 418 ha near the Hudson-Meng Bison Bonebed in NW Nebraska. These approaches can significantly improve the accuracy of survey data....