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Glendale, AZ, United States

Kretzmann M.,Glendale College | Rohrbach L.,Long Island University | Durham K.,Riverhead Foundation for Marine Research and Preservation | DiGiovanni Jr. R.,Riverhead Foundation for Marine Research and Preservation | Sanudo-Wilhelmy S.,University of Southern California
Aquatic Mammals | Year: 2010

Toxic (e.g., Hg, Ag, Cd, and Pb) and essential (e.g., Se, Cu, and Fe) trace element levels were determined in liver samples from four seal species (harp seal [Phoca groenlandica], n = 35; hooded seal [Cystophora cristata], n = 7; harbor seal [Phoca vitulina], n = 34; gray seal [Halichoerus grypus], n = 10) stranding in Long Island waters between 1988 and 2004 to examine temporal and species-specific patterns in these top marine carnivores. There was no obvious trend in trace metal burdens in seal livers over this time period. Harp and hooded seals are arctic species that have only appeared in Long Island waters in recent years. Their diets are believed to include more invertebrate prey, and this was reflected in significantly higher cadmium (Cd) concentrations (mean = 5.5 to 6.3 μg g-1 dry weight vs. 0.5 to 1.4 μg g-1 for harbor and gray seals, p = 0.007). The highest mercury (Hg) burdens (> 100 μg g-1 dry weight) were seen in seven of the eight adult harbor seals and the only adult gray seal; four of five adult harp seals did not show elevated levels. This suggests that migratory harp seals are feeding on prey with a lower Hg burden compared to resident harbor seals that forage in the coastal environment. Copper (Cu) levels were high (70 to 105 μg g-1) in a few juvenile harbor seals as predicted based on Cu-incorporating enzymes essential for growth. A few elevated silver (Ag) values (1.5 to 3.0 μg g-1) were seen in the same adult harbor seals with high Hg burdens. These values may not reflect metal burdens in healthy populations as our samples were obtained from stranded animals, but there was no evidence that any of these seals died as a result of metal toxicity.

Lemoyne R.,University of California at Los Angeles | Mastroianni T.,Cognition Engineering | Kale H.,Glendale College | Luna J.,Glendale College | And 5 more authors.
Journal of Mechanics in Medicine and Biology | Year: 2011

An intrinsic aspect of the standard neurological examination is the deep tendon reflex. A clinician is tasked with qualitatively evaluating reflex parameters, such as reflex response and latency. The tendon reflex is capable of providing preliminary insight with respect to dysfunction of the central and peripheral nervous systems. The qualitative assessment of the tendon reflex can be classified through the implementation of an ordinal scale, such as the NINDS scale which spans five ordinal components from 0 to 4. The reliability and accuracy of the ordinal-scale method for classifying reflex characteristics have been demonstrated to be an issue of controversy. Ordinal scales lack the capacity to properly classify the temporal features of the tendon reflex. Electrodiagnostic testing traditionally provides higher fidelity evaluation of peripheral neuropathy; however, a study by Cocito et al., has discovered 28% of the prescriptions were inappropriate. The fourth-generation wireless reflex quantification system provides a less resource intensive, highly accurate, reliable, and reproducible alternative. The patellar tendon reflex is evoked through a predetermined potential energy derived swing arm attached to a standard reflex hammer. Tandem wireless 3D MEMS accelerometers quantify reflex response and latency. The reflex response maximum and minimum are acquired from the wireless 3D MEMS accelerometer positioned above the ankle joint. The latencies derived from the maximum and minimum of the reflex responses are derived from the temporal disparity relative to the acceleration waveforms of the reflex response and swing arm evoking the tendon reflex. The fourth-generation wireless reflex quantification system has been evolved with a more user-convenient wirelessly activated datalogger mode, which is subsequently downloaded to a local PC wirelessly. The wireless datalogger mode enables sampling at a greater rate relative to the real-time streaming data mode. An automated MATLAB software program is implemented for acquiring reflex parameters. Enclosed is the longitudinal study of the fourth-generation wireless reflex quantification system that demonstrates considerable precision for accuracy, reliability, and reproducibility. As a supplement to the research, a brief reflex modulation study is amended to the longitudinal study. © 2011 World Scientific Publishing Company.

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