Multiplafform sampling (ship, aircraft, and satellite) of a Gulf Stream warm core ring

The purpose of this paper is to demonstrate the ability to meet the need to measure distributions of physical and biological properties of the ocean over large areas synoptically and over long time periods by means of remote sensing utilizing contemporaneous buoy, ship, aircraft, and satellite (i.e., multiplatform) sampling strategies. A mapping of sea surface temperature and chlorophyll fields in a Gulf Stream warm core ring using the multiplatform approach is described. Sampling capabilities of each sensing system are discussed as background for the data collected by means of these three dissimilar methods. Commensurate space/time sample sets from each sensing system are compared, and their relative accuracies in space and time are determined. The three-dimensional composite maps derived from the data set provide a synoptic perspective unobtainable from single platforms alone.

Splanchnic artery aneurysms and pseudoaneurysms: transcatheter embolization

Over the past 7 years, eight patients with splanchnic artery aneurysms and pseudoaneurysms were studied and treated. Transcatheter embolization resulted in occlusion of the lesions in all eight patients. Potentially risky and difficult surgery was avoided completely in four patients. Three patients had elective surgery at a later date when their condition was more stable. The remaining patient had definitive surgery after embolization. Transcatheter embolization should be the initial treatment of choice in splanchnic artery aneurysms and pseudoaneurysms.

Percutaneous transluminal angioplasty of the renal arteries: double-catheter technique

A technique is described for angioplasty of the renal arteries using two catheters in a patient with two renal arteries to the left kidney. Injury to the nonstenotic supplemental artery during balloon dilatation of the stenotic main artery was avoided with the use of this technique.

Endothelialization of human collagen surfaces with human adult endothelial cells

Artificial vascular grafts are currently used to restore blood flow to ischemic tissue. Although the long-term patency of large diameter grafts is relatively acceptable, small diameter (less than 4 mm) grafts exhibit poor long-term patency rates. One technique to create a nonthrombogenic surface on artificial prostheses has been to seed with endothelial cells derived from autologous vessels. We have examined the interaction of human adult endothelial cells with the natural collagen surfaces presented by human amnion. Scanning electron microscopic evaluation revealed that human adult endothelial cells adhered rapidly to both the basement surface (collagen types IV and V) and interstitial surface (collagen types I and III) of amnion. However, the adherence of cells was significantly greater on the basement membrane surface. In addition, human adult endothelial cells rapidly formed close cell-to-cell interactions on basement membrane as compared with cells seeded onto the interstitial surface. These results suggest that seeding of endothelial cells onto artificial surfaces will be facilitated if the surface simulates the natural basement membrane to which endothelial cells natively adhere.

Phytoplankton Blooming Off the U.S. East Coast: A Satellite Description

A "bloom" of near-surface phytoplankton occurs in the Atlantic Slope region of the western Atlantic Ocean off the U.S. East Coast in the spring. Satellite time series of sea-surface temperature and phytoplankton pigment concentration, derived from measurements of the National Oceanic and Atmospheric Administration NOAA-7 Advanced Very-High-Resolution Radiometer and the National Aeronautics and Space Administration Nimbus-7 Coastal Zone Color Scanner, respectively, give information on the spatial extent and temporal development of such a bloom for a 28-day period in April through May 1982. The phytoplankton concentration of the slope area is comparable to that of the Atlantic Shelf. Total primary productivity of the slope during this period is equivalent to that of the shelf. The primary productivity within a warm-core ring and in the Gulf Stream system is less by a factor of 2.

Optical properties of the clearest natural waters (200-800 nm)

A new UV submersible spectroradiometer has been employed to determine the diffuse attenuation coefficient for irradiance in the clearest natural waters [K(w)(lambda)] with emphasis on the spectral region from 300 to 400 nm. K(w)(lambda) can be related to the inherent optical properties of pure water, in particular the total absorption coefficient a(w)(lambda) and the molecular scattering coefficient b(m)(lambda), by means of equations derived from radiative transfer theory. We present an analysis showing that limiting values of K(w)(lambda) can be estimated from a(w)(lambda) and vice versa. Published a(w)(lambda) data, which show discrepancies much larger than their estimated accuracies, are briefly reviewed and then compared, via our analysis, with K(w)(lambda) data (our own new and previously published data as well as relevant data of others). This comparative analysis and new data allow a consistent and accurate set of optical properties for the clearest natural waters and for pure fresh water and saltwater to be estimated from 300 to 800 nm.

Stratospheric Ozone, Middle Ultraviolet Radiation, and Carbon-14 Measurements of Marine Productivity

The effects of increased ultraviolet radiation, due to decreased stratospheric ozone, on marine phytoplankton have been investigated with the use of static bottle in situ carbon-14 productivity measurements. The relative biological efficiency for photoinhibition may be used to calculate biologically effective doses and resultant amplification factors. The carbon-14 technique (short-term incubations) is inadequate for assessment of possible large amplification factor photoprocesses that may be ecologically significant.