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Census of dinosaur skin reveals lithology may not be the most important factor in increased preservation of hadrosaurid skin

100%

Davis M.

Acta Palaeontologica Polonica

2014

tom 59

nr 3

A global census of published records of dinosaur skin from the Mesozoic, cross-referenced against a more detailed lithological dataset from the Maastrichtian of North America, clarifies why most examples of fossilized dinosaur skin come from hadrosaurids. Globally, more published specimens of hadrosaurids exhibit preserved skin than any other major clade of dinosaur. North American Maastrichtian hadrosaurid fossils are 31 times more likely to have skin preserved than coeval dinosaur remains. This does not arise from collection methodology, the large population size of hadrosaurids, or the gross lithology of their depositional environment. The reason that so many hadrosaurid fossils have skin is still elusive, but was likely something intrinsic to hadrosaurids that originated early on in the clade, perhaps the possession of tougher or thicker skin. The database of published examples of fossilized dinosaur skin assembled here will assist the continued development of a much needed common terminology and taxonomic framework for dinosaur skin.

A Methodology for Assessing Blast Protection in Explosive Ordnance Disposal Bomb Suits

32%

Bass C. , Davis M. , Rafaels K. , Rountree M. , Harris R. M. , Sanderson E. , Andrefsky W. , DiMarco G. , Zielinski M.

International Journal of Occupational Safety and Ergonomics

2005

tom Vol. 11, No. 4

347--361

To reduce human casualties associated with explosive ordnance disposal, a wide range of protective wear has been designed to shield against the blast effects of improvised explosive devices and munitions. In this study, 4 commercially available bomb suits, representing a range of materials and armor masses, were evaluated against 0.227 and 0.567 kg of spherical C-4 explosives to determine the level of protection offered to the head, neck, and thorax. A Hybrid III dummy, an instrumented human surrogate [1], was tested with and without protection from the 4 commercially available bomb suits. 20 tests with the dummy torso mounted to simulate a kneeling position were performed to confirm repeatability and robustness of the dummies, as well as to evaluate the 4 suits. Correlations between injury risk assessments based on past human or animal injury model data and various parameters such as bomb suit mass, projected area, and dummy coverage area were drawn.

Injury Risk in Behind Armor Blunt Thoracic Trauma

32%

Bass C. R. , Salzar R. S. , Lucas C. R. , Davis M. , Donnellan L. , Folk B. , Sanderson E. , Waclawik S.

International Journal of Occupational Safety and Ergonomics

2006

tom Vol. 12, No. 4

429--442

First responders and military personnel are particularly susceptible to behind armor blunt thoracic trauma in occupational scenarios. The objective of this study was to develop an armored thorax injury risk criterion for short duration ballistic impacts. 9 cadavers and 2 anthropomorphic test dummies (AUSMAN and NIJ 0101.04 surrogate) were tested over a range of velocities encompassing low severity impacts, medium severity impacts, and high severity impacts based upon risk of sternal fracture. Thoracic injuries ranged from minor skin abrasions (abbreviated injury scale [AIS] 1) to severe sternal fractures (AIS 3+) and were well correlated with impact velocity and bone mineral density. 8 male cadavers were used in the injury risk criterion development. A 50% risk of AIS 3+ injury corresponded to a peak impact force of 24,900 ± 1,400 N. The AUSMAN impact force correlated strongly with impact velocity. Recommendations to improve the biofidelity of the AUSMAN include implementing more realistic viscera and decreasing the skin thickness.

Wielki kanjon rzeki Kolorado

26%

Davis M.

nr 33