Publications by authors named "John C Brock"

Coral reef ecosystem management benefits from continual quantitative assessment of the resources being managed, plus assessment of factors that affect distribution patterns of organisms in the ecosystem. In this study, we investigate the relationships among physical, benthic, and fish variables in an effort to help explain the distribution patterns of organisms on patch reefs within Biscayne National Park, FL, USA. We visited a total of 196 randomly selected sampling stations on 12 shallow (<10 m) patch reefs and measured physical variables (e.

View Article and Find Full Text PDF

The effects of grazing by feral horses on vegetation and dune topography at Assateague Island National Seashore were investigated using color-infrared imagery, lidar surveys, and field measurements. Five pairs of fenced and unfenced plots (300 m2) established in 1993 on sand flats and small dunes with similar elevation, topography, and vegetation cover were used for this study. Color-infrared imagery from 1998 and field measurements from 2001 indicated that there was a significant difference in vegetation cover between the fenced and unfenced plot-pairs over the study period.

View Article and Find Full Text PDF

An approach for the replacement of the distal ascending aorta-proximal arch and acute dissection is described. During the operation, the patient's entire body was continuously perfused, the aortic arch was excluded from the arterial circulation, and the aorta was not clamped at any time. To achieve continuous body perfusion, we independently cannulated the right axillary and the left femoral arteries.

View Article and Find Full Text PDF