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Midgut glands of abalone Haliotis discus contained two acid phosphatases [orthophosphoric-monoester phosphohydrolase (acid optimum), EC 3.1.3.2] separable by phosphocellulose column chromatography. They were designated as acid phosphatases I and II in order of elution and were purified 99- and 290-fold, respectively. Purified acid phosphatase II was nearly homogeneous as judged by polyacrylamide gel electrophoresis. The substrate specificity of acid phosphatase I was narrow, whereas that of acid phosphatase II was broad. Good substrates for acid phosphatase I included p-nitrophenyl phosphate, phosphoenolpyruvate, inorganic pyrophosphate, and nucleoside di- and triphosphates. The acid phosphatases did not require any metal ion for maximum activity and were inhibited by Zn2+, Cu2+ and Hg2+. Fluoride and arsenate were potent inhibitors of both enzymes. The pH optima of acid phosphatases I and II were 5.9 and 5.5, respectively. The molecular weights of acid phosphatases I and II were estimated to be 28,000 and 100,000, respectively, by gel filtration on Sephadex G-100. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis suggested that acid phosphatase II consists of two identical subunits.

1. 1. The effects of compound 48/80 on cholinergic nerve transmission and on the liberation of histamine in the isolated chick oesophagus were investigated. 2. 2. Compound 48/80 (0.2–1 μg ml −1 ) potentiated the cholinergic nerve-induced contraction and caused the contraction of the oesophagus itself. The latter response was prevented by atropine, tetraodotoxin and mepyramine but not by metiamide. 3. 3. Compound 48/80 released dose-dependently endogenous histamine from the isolated chick oesophagus. 4. 4. These results suggest that the action of compound 48/80 is mediated by the release of histamine from an endogenous pool and that histamine released endogenously facilitates the release of ACh from the intrinsic cholinergic nerve in the chick oesophagus.

Nonspecific cross-reacting antigen (NCA) is a member of the carcinoembryonic antigen (CEA) gene family. Recently, a DN A segment for part of the human NCA gene was isolated and sequenced. We mapped this gene by Southern blot analysis of hybrid cells and by in situ hybridization. The Southern blot analysis indicated that the NCA gene is on human chromosome 19 and the in situ hybridizations localized the gene to band 19ql3.2.

Scale-model field and wind tunnel experiments were conducted to examine the inflowand similarity considerations for flow behind a building. In both cases the model was simplified to a two-dimensional fence placed perpendicular to the oncoming wind, and the nondimensionalized cavity wake length, L c /H, was the flow characteristic examined. In the field, the flow downwind of the fence was visualized with a gridlike arrangement of wind vanes. It was found that L c /H increases with increasing Returb D U t decreases with increasing atmospheric stability. In the wind tunnel, upwind surface roughness and thermal stability were varied. Over a range of stabilities from unstable to stable, it was found that in the stable region L c /H decreases rapidly as stablity increases while in the unstable region L c /H decreases only slightly as the flow becomes more unstable. By changing the surface roughness, the turbulent Reynolds number was varied from approximately 15 to 60(keeping the model well within the surface boundary layer, H/δ ≥ 0.2). As Re turb increases, L c /H increases. A comparison of the field and wind tunnel data shows that in both, L c /H increases with increasing Returb. This relationship is not linear, but seems to approach an upper limit, perhaps the L c /H = 17 found by Arie and Rouse. Additionally, it was found that in both studies that as the local turbulent intensities increase, L c /H decreases.