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Identification of a low-level point radiation source amidst background radiation is achieved by a network of radiation sensors using a two-step approach. Based on measurements from three sensors, the geometric difference triangulation method is used to estimate the location and strength of the source. Then a sequential probability ratio test based on(More)
STUDY DESIGN An in vivo study of the biologic and biomechanical consequences of static compressive loading on the mouse tail intervertebral disc. OBJECTIVES To determine whether static compression in vivo alters the biologic activity of the disc and leads to diminished biomechanical performance. SUMMARY OF BACKGROUND DATA Static compressive stress that(More)
A high-performance liquid chromatographic method for the determination of catecholamines and serotonin, their precursors and their main metabolites was developed applied to rat cerebellum, hypothalamus, striatum and cortex. A fluorimetric and an oxidative amperometric detector were used in series. For both detectors, detection limits (25-520 pg) were useful(More)
The localization of a radioactive source can be solved in closed-form using 4 ideal sensors and the Apollonius circle in a noise- and error-free environment. When measurement errors and noise such as background radiation are considered, a larger number of sensors is needed to produce accurate results, particularly for extremely low source intensities. In(More)
Identification of a low-level point radioactive source amidst background radiation is achieved by a network of radiation sensors using a two-step approach. Based on measurements from three or more sensors, a geometric difference triangulation method or an <i>N</i>-sensor localization method is used to estimate the location and strength of the source. Then a(More)
Detection, identification, and tracking (DIT) problems that arise in applications such as the protection of people and the environment against radiational, biological, and chemical plumes, can be solved by combining the modalities of sensor and cyber networks. The sensor network provides information about physical space activities, such as the locations and(More)
The Center for Adaptive Optics Treasury Survey (CATS) aims to combine deep HST images in the optical with deep Keck adaptive optics (AO) data in the near-infrared (NIR) to study distant galaxies, AGN, and supernovae. We recently achieved an important new milestone by securing the first Keck laser guide star AO image of faint galaxies. Six galaxies with(More)
STUDY DESIGN An in vivo study of the toxic consequences of static compressive stress on the intervertebral disc. OBJECTIVES To determine whether disc cell death is correlated with the magnitude and duration of spinal compressive loading. SUMMARY OF BACKGROUND DATA Static compression in vivo has been demonstrated to induce cell death. Cell death, in(More)
BACKGROUND CONTEXT Intervertebral disc cell function in vitro has been linked to features of the local environment that can be related to deformation of the extracellular matrix. Epidemiologic data suggest that certain regimens of spinal loading accelerate disc degeneration in vivo. Yet, the direct association between disc cell function, spinal loading and(More)
A reversed-phase high-performance liquid chromatographic method has been developed for the simultaneous determination of 5-hydroxytryptophan, 5-hydroxyindoleacetic acid, N-acetylserotonin, tryptophan, 5-hydroxytryptamine (serotonin) and melatonin in rat pineal using a buffered aqueous eluent containing acetonitrile and methanol as organic modifiers and an(More)