Detection of explosives has the flavor of those mathematical problems that are not invertible. It is easier to hide explosives than to find them. Many approaches have been proposed and executed for the remote detection of explosives, contraband materials, weapons of mass destruction, currency, etc. Most detection technologies suffer from a common problem: the features they look for, such as discontinuties in electrical conductivity, are not unique properties of the target but are contained, to some degree, in the more benign surroundings. Such a degeneracy leads to "clutter" in the response. For example, resolving the false alarms generated by this clutter can determine the rate of advance of a conventional electromagnetic metal detector employed as a landmine detector. One approach that provides a "unique" signature is nuclear quadrupole resonance (NQR) (the technique is also called QR, to avoid confusion with strictly nuclear techniques). This paper outlines the important physical principles behind the use of NQR for remote detection, indicates areas of applicability, and presents recent results of field trials of a prototype landmine detection system.

Bone mass measurement (BMM) is useful to identify persons with low bone mass who are at increased risk for fracture. Given the increased emphasis that is being placed on preventive services such as screening for osteoporosis, we evaluated trends in BMM among Medicare beneficiaries. We studied a 5% sample of Medicare beneficiaries Ն65 yr of age in 1999-2005. We identified claims for BMM tests performed in both facility and nonfacility settings, evaluated temporal trends in use of these tests, and described the proportion of tests attributable to each specialty of physicians submitting claims. We also assessed patterns of serial testing among individuals who were tested more than once. Claims data from all years were pooled to describe the proportion of persons in the population ever tested. From 1999 to 2005, use of central DXA increased by ∼50%, and use of peripheral DXA declined. The greatest increases in central DXA occurred among internists, family practitioners, and gynecologists. In 1999, the proportion of 65-yr-old women tested was 8.4%; this increased to 12.9% in 2005. Corresponding proportions for men were 0.6% and 1.7%, respectively. Between 40% and 73% of persons receiving central DXA were retested, most at ∼2-yr intervals. Aggregating data across all years for whites and blacks, 30.0% of women and 4.4% of men underwent central DXA at least once. We conclude that, although use of DXA steadily increased from 1999 to 2005, only ∼30% of women and 4% of men at least 65 yr old had a central DXA study. Given the importance of central DXA to assess the risk of osteoporotic fractures, strategies to increase central DXA use to test at-risk persons are warranted. ONE MASS MEASUREMENT (BMM) is a well-validated and widely accepted screening test to identify patients with low bone mass who are at increased risk for fragility fractures. Because osteoporosis is clinically asymptomatic until a fracture occurs, the importance of screening during the asymptomatic phase is critical to identify opportunities to mitigate risk.(1) There are many types of BMM testing technologies, including ultrasound, QCT, and both singleand dual-energy X-ray absorptiometry. Among these, DXA of central sites (lumbar spine, femoral neck, total hip) is preferred because of its precision, minimal radiation exposure, relatively low cost, and largest evidence base to support diagnostic and treatment guidelines.Numerous international agencies recommend primary screening with DXA for at-risk persons. In the United States, the National Osteoporosis Foundation and the U.S. Preventive Task Force recommend population-wide DXA for all women at least 65 yr old and for younger women with risk factors.(2-4) Screening with central DXA for all women Ն65 yr of age also is recommended by Medicare as one of the reimbursable quality measures that is part of the 2007 Physician Quality Reporting Initiative (PQRI). There is less consensus on the appropriate screening age for men at average risk, although the International Society for Clinical Densitometr...

Nursing facilities provide skilled nursing and rehabilitative care to patients for short stays and custodial care to patients for long stays. The type of nursing facility stay (short-or long-term) is a potentially important risk factor and health outcome in health services research and is informative from both medical and fiscal perspectives. The purpose of this study was to develop and validate an algorithm to identify the use of nursing facility services and differentiate short-from long-term care using Medicare claims data. We used claims data for a 5% sample of Medicare beneficiaries to develop an algorithm to detect the use of nursing facility services and to distinguish between short-and long-term stays. We tested this algorithm using residency status from Medicaid long-term care claims for dually eligible beneficiaries and using residency status from the Medicare Current Beneficiary Survey (MCBS). Among 1,694,051 beneficiaries included in the baseline cohort, 25.6% had some indication of nursing facility residency. Using our algorithm, 59.8% of beneficiaries using any nursing facility care were classified as long-term residents. Validation of the algorithm against Medicaid long-term care claims and MCBS yielded high sensitivity and specificity. To our knowledge, this is the first paper to present a

Abstract-Wearable electrocardiograph (ECG) monitoring systems today use electrodes that require skin preparation in advance, and require pastes or gels to make electrical contact to the skin. Moreover, they are not suitable for subjects at high levels of activity due to high noise spikes that can appear in the data. To address these problems, a new class of miniature, ultra low noise, capacitive sensor that does not require direct contact to the skin, and has comparable performance to gold standard ECG electrodes, has been developed. This paper presents a description and evaluation of a wireless version of a system based on these innovative ECG sensors. We use a wearable and ultra low power wireless sensor node called Eco. Experimental results show that the wireless interface will add minimal size and weight to the system while providing reliable, untethered operation.

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