This work is aimed at developing a protocol based on surface limited redox replacement (SLRR) of underpotentially deposited (UPD) Pb layers for the growth of epitaxial and continuous Pt thin films on polycrystalline and single crystalline Au surfaces. Different from previously reported papers using SLRR in multiple immersion or flow cell setups, this work explores the one-cell configuration setup as an alternative to improve the efficiency and quality of the growth. Open circuit chronopotentiometry and quartz-crystal microbalance experiments demonstrate steady displacement kinetics and a yield that is higher than the stoichiometric Pt(II)-Pb exchange ratio (1:1). This high yield is attributed to oxidative adsorption of OH(ad) taking place on Pt along with the displacement process. Also, ex situ scanning tunneling microscopy surface characterization reveals after the first replacement event the formation of a dense Pt cluster network that homogenously covers the Au surface. The Pt films grow homogenously with no significant changes in the cluster distribution and surface roughness observed up to 10 successive replacement events. X-ray diffraction analysis shows distinct (111) crystallographic orientation of thicker Pt films deposited on (111) textured Au thin films. Coarse energy dispersive spectroscopy measurements and finer X-ray photoelectron spectroscopy suggest at least 4 atom % Pb incorporating into the Pt layer compared to 13 atom % alloyed Cu when the growth is carried out by SLRR of Cu UPD.

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Powerful spirits called boramey possess mediums in Cambodia. In this article the proce dures used in the attribution and recognition of boramey names is described, and a typol ogy of these spirits is offered based on their identity and history. Specific and well-known roles that influence the attitudes or believers are delineated in order to show how the identities of the medium and the boramey interlink. The resurgence of these mediumistic practices is explained in the context of the recent history of Cambodia and in rela tion to the turmoil faced by individuals in a society confronted with rapid changes.

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Two years ago Dr. Ackermann 1 succeeded in obtaining from histidine by putrefaction a base which has been identified with 3-imidazolethylamine prepared at first synthetically by Windauss and Vogt. Since then G. Barger and H. Dale 3 in England, and Kutscher 4 in Germany discovered this amine in ergot, where it is one of the most active principles. The physiological action of 6-imidazolethylamiiie has been fully studied by H. Dale and P. Laidlaw in rodents and carnivora ; they noted that a dose of 0'5 5 mgm. injected in the external saphenous vein of a large guinea-pig (about 900 grm.) caused death quickly with symptoms very similar to those obtained in anaphylactic shock. They killed a medium-sized rabbit by injection of 4 mgm. in the ear vein, with the same symptoms. With subcutaneous injections of larger doses the rate of respiration was increased, and then occurred defsecation and micturition, with prostration and some degree of narcosis ; gradually recovery took place. In the cat an injection into the long saphenous vein of 2 to 10 mgm. caused vomiting, salivation, and defalcation, and at the same time the respiration became laboured, the animal showing signs of prostration and light narcosis with con--striction of the pupils. Same action with bigger doses injected subcutaneously ; recovery set in gradually.We experimented on the same animals with hydrochloride of fl-imidazolethylamine prepared by the action on histidine ,of putrefactive bacteria, for which we are indebted to the kindness of F. Hoffmann-La Roche, and had exactly the same results. We tried then to note the physiological action of this amine in monkeys (Macacus sinicus and Macacus -cynomolgus), weighing 1100-1300 grm., by intravenous injection into the posterior saphenous vein. G The effects obtained with these monkeys were very similar to those obtained with the carnivora-that is, vomiting and diarrhoea, profuse salivation, and a well-marked respiratory impediment.The lethal dose was 65 mgm.-that is, about 50 mgm. per kilo of animal.The monkey showed the ordinary symptoms, more marked; then followed a full paralysis of the posterior limbs, and after a while of the anterior ones ; at the same time spasmodic contraction of the diaphragm. The animal was sprawling, the head sank 1 Ackermann: Zeitschrift für Physiologische Chemie, lxv., p. 504, 1910. 2 Windauss and Vogt: Berichte der Deutschen on the table, and it died in 20 minutes. Post mortem the lungs were found distended ; the heart stolped in diastole.Barger and Dale isolated (3-imidazolethylamine from intestinal extract, and they thought that this ptomaine in the intestinal mucous membrane could be due to the resorption of the base produced in the intestinal digestion by the action of some kinds of bacteria on histidine set free by enzymic or microbial hydrolysis of proteins. Control of this hypothesis being valuable in man to throw some light on the pathogenesis of different symptoms of so-called autointoxication, we tried to isolate from human stools bacteria able to produce (3-imidazo...