Biomedical sciences instrumentation
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Cardiac output (CO) is an important indicator of cardiovascular function. Several invasive and non-invasive methods have been developed and validated to assess CO in the clinical setting. These are often computationally complex or proprietarily-restricted, and thus, not feasible in ambulatory investigations and the laboratory research setting. ⋯ Baseline beat-to-beat blood pressure data from 67 young (mean age = 19.94± 2.8), healthy men (n = 30) and women (n = 37) was available for analysis. Overall, the correlation of COEST and CO was moderate (r = .42, p <.0001) and stronger in men (r = .66, p < .0001) compared to women (r = .36, p < .05). These results suggest that at least in some situations the Liljestrand and Zander method may provide an adequate measure of CO when other methods are not available.
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When evaluating occupant motions during driving tasks, it is desirable to have a well-established correlation between vehicle and occupant accelerations. Therefore, this study demonstrated a methodology to quantify accelerations experienced by the driver of a passenger vehicle and compare them to associated vehicle motions. Acceleration levels were measured at the seat and the drivers head, cervical spine, and lumbar spine during six non-collision driving tasks. ⋯ Peak body accelerations were less than 1.2 g, including 0.82 g lumbar acceleration during heavy braking and 0.88 g head acceleration during the curb mount. These preliminary measurements are comparable to or lower than accelerations experienced during non-driving activities such as sitting quickly. This study contributes to the scientific understanding of accelerations experienced by vehicle occupants and demonstrates the potential to relate vehicle and occupant accelerations during common driving activities that do not involve collisions.
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Detection of occult injuries, which are not easily recognized and are life-threatening, in motor vehicle crashes (MVCs) is crucial in order to reduce fatalities. An Occult Injury Database (OID) was previously developed by the Center for Transportation Injury Research (CenTIR) using the National Automotive Sampling System Crashworthiness Data System (NASS-CDS) 1997-2001 which identified occult and non-occult head, thorax, and abdomen injuries. The objective of the current work was to develop an occult injury model based on underlying injury characteristics to derive an Occult Score for common MVC-induced injuries. ⋯ Of the considered injuries, it was determined that 54% of head, 26% of thorax, and 23% of abdominal injuries were occult injuries. No occult injuries were identified in the face, spine, upper extremity, or lower extremity body regions. The Occult Score generated can be useful in advanced automatic crash notification research and for the detection of serious occult injuries in MVCs requiring prompt treatment at a trauma center.
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Programmable, implantable and external biomedical devices (such as pacemakers, defibrillators, insulin pumps, pain management pumps, vagus nerve stimulators and others) may be vulnerable to unauthorized access, commonly referred to as hacking. This intrusion may lead to compromise of confidential patient data or loss of control of the device itself, which may be deadly. Risks to health from unauthorized access is in addition to hazards from faulty (buggy) software or circuitry. ⋯ In this paper the author discusses these issues, reviewing known problems and zero-day threats, with potential solutions. He outlines his approach to secure software and hardware challenges using the Forth language. A plausible scenario is described in which hacking of an implantable defibrillator by terrorists results in a severe national security threat to the United States.
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Longitudinal barriers, such as guardrails, are designed to prevent a vehicle that leaves the roadway from impacting a more dangerous object while minimizing risk of injury to the vehicle occupants. Current full-scale test procedures for these devices do not consider the effect of occupant restraints such as seat belts and airbags. The purpose of this study was to determine the extent to which restraints are used or deployed in longitudinal barrier collisions and their subsequent effect on occupant injury in these collisions. ⋯ Seat belt usage rates were approximately 60 and 80 percent for non-airbag-equipped and airbag-equipped vehicles, respectively. Compared to fully restrained occupants, relative risk of injury for no airbag/belted, airbag/unbelted, and no airbag/unbelted occupants was 1.6, 7, and 11.7, respectively. Despite these large differences in relative risk, however, 95 percent of the occupants in the analyzed data were either uninjured or sustained minor injury, which reinforces the overall effectiveness of these roadside devices.