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A novel series of thiopyridyl triazine ligands and their metal(II) complexes have been synthesized. The X-ray structure of the mononuclear copper(II) complex of the ligand 6-thiopyridyl-2,4-bis(dimethylamino)-l,3,5-triazine (L5) has also been determined. The in vitro cytotoxic potency against the human colon cancer cell line (HT-29) has been determined for the ligands and their platinum complexes. All compounds including their ligands have been found to be highly potent against the HT-29 cell line. The ligand 2,4,6-trithiopyridyl-l,3,5-triazine (L2) and its platinum complex were found to be 10–30 times more potent than cisplatin.

This article describes the kind of work done by the proposal writer in the aerospace industry and then offers suggestions on how educational institutions can better prepare their students for this work.

Volume changes at a mercury cathode in hydrogen-saturated aqueous 0.1 M hydrochloric acid during electrolysis at 25 °C are less than those predicted by Faraday's Law[Formula: see text]over a range of current densities from 0.4 to 83 μA mm−2. Difficulties attributable to the anodic reaction of mercury were found using an apparatus similar to that of Müller (1) but constructed entirely of glass. A two-compartment cell proved to be advantageous in isolating the cathode reaction. Rates of volume change attributable to formation of H2(g) almost invariably increased with time of electrolysis but were always below expectation. In agreement with Müller, an increase of volume was observed after electrolysis. The evidence is consistent with formation and subsequent decomposition of a hydrogen amalgam. It suggests that, contrary to the usual assumptions (2), hydronium-ion discharge is not the slowest step in the overall hydrogen gas-producing reaction.

A technical editor does three things in editing technical illustrations: (1) he makes changes in the rough art sketched out by the originator; (2) he makes changes in the finished art prepared by the illustrator; and (3) he makes changes in the production art that is prepared for printing. The editor and illustrator are mutually dependent on each other in the task of producing clear graphical supplements to the text, and they should therefore cooperate closely with each other.

WHEN in June, 1782, the Bald Eagle (Haliaeetus leucocephalus) was chosen for our national emblem, the bird was fairly common throughout most of the United States where conditions were suitable. Since then it has been exterminated over most of its original range and is found today only where law or seclusion give it protection. It has been my fortune to observe the Eagle in one of these remaining strongholds and to study its food habits at two nests. One of these nests which it was possible to examine carefully yielded much interesting information about the food and habits of the Eagle in this type of environment. The location of the nests was the Eastern Shore of Maryland, which with two counties of Virginia and the state of Delaware, constitutes the peninsula of land which cuts Chesapeake Bay off from the Atlantic Ocean. The land in the area where the nests were located is very low and much of it consists of marsh and swamp land. It is drained by Blackwater River, a sluggish stream, fresh at its head but brackish and nearly salt at its mouth. The river flows through the great Blackwater Marshes which are dotted with ponds and small pine-clad elevations known as islands. Along the borders of the marsh are growths of trees which in some places extend back for several miles. These areas are flooded at every heavy rain and during the winter months, and are known as swamps. The chief trees in these swamps are loblolly pine, sweet gum, holly, and white and willow oaks. The one in which the first Eagles' nest was located is known as Gum Swamp. The Blackwater marshes are famous for their muskrat population and for the great number of water-fowl that winter in the ponds and on the river. The river also has an abundance of fish. The old Eagles evidently had an eye on these bounties of nature when they established their lofty eyrie at the edge of the marsh so long ago. The nest was located some two hundred yards from the open marsh and less than a mile from Blackwater River. It was about seven miles to the waters of Chesapeake Bay and less than three quarters of a mile to the nearest house. The original nest had been located for no one knows how long in a big pine far back in the swamp. Some thirty years ago the tree was cut and the Eagles then moved to the giant pine near the edge of the marsh. Here for over thirty years their nest was located until the hurricane of August 22, 1933, came sweeping across the marsh and tore the great nest from its place. The nest was not in use when destroyed, in fact no attempt had been made to rear a brood there for three years. A local egg collector had paid it yearly visits until the Eagles ceased to breed there. They still

Radiochemical and electrochemical evidence is presented that electrochemically generated tritium and hydrogen atoms permeate through lead foil at measureable rates at room temperature. The permeation process is controlled by diffusion through the metal lattice, Fick's First Law being obeyed by both H and 3H atoms. Using earlier measurements of the diffusivity of H in Pb, H and 3H concentrations of 4 × 10−7 and 9 × 10−13 g-atom cm−3 are computed for a current density of 53 mA cm−2 at the Pb cathode surface.The overall hydrogen-tritium separation factor, ST is apparently 0.3 ± 0.15, in contrast to Bockris and Srinivasan's 6.7 and 7.2 for cathodic gas evolution from acidic and alkaline media, respectively. Reasons are suggested for this large difference.

Residual oxygen concentrations of about 5·10 −7 M have been measured, in nitrogen- and hydrogen-saturated buffer solutions by the coulostatic method using a hanging mercury-drop electrode. Light pre-electrolysis of the buffer solutions was found to cause very little alteration of the measured values but under some conditions the apparent oxygen concentration became much smaller and other phenomena made their appearance. These phenomena were accentuated when the hydrogen used was strongly deoxygenated. In the region of the first oxygen wave, a mass transfer-controlled oxidation was then predominant, no oxygen reduction currents being observable, but at much more negative potentials a pseudocapacity was observed, a more or less stable rest potential (having a range of values) being attained in a few seconds almost regardless of the coulostatic charge applied. It seems probable that a redox couple is responsible but the occurrence of similar phenomena in two different buffers makes an impurity effect less likely.

Conclusive evidence is reported for the permeation of electrolytic hydrogen through lead. The diffusion coefficient at 25 °C lies between 10−7 and 10−6 cm2 s−1 while the bulk concentration of dissolved hydrogen is indicated to be 10−6 g-atom cm−3 at current densities of 10 to 50 mA cm−2.

Exchange current densities and enthalpies of activation for the Fe2+–Fe3+ redox reaction depend on the nature of the metal electrode in sulphate medium, ΔH‡ being 6·0 kcal g ion–1 at Pt and 8·5 kcal g ion–1 at Pd; in 6M HCl, however, ΔH‡ is almost independent of the metal, being 4·0 and 3·6 kcal g ion–1, respectively, at Pt and Pd.

Much interest has been shown recently in the separation of deuterium from hydrogen by the use of palladium and its alloys. Pd--Ag alloys are of particular interest because of the high permeation rates that can be achieved without serious mechanical distortion of the kind that occurs with Pd. The authors have measured the separation factors for the gas evolved on the cathode side of alloy foils and for the gas produced after diffusion through the foils and subsequent combination. The measurements have utilized mass spectrometric analysis of the gases which enabled the authors to simultaneously compare the separation factors on both sides of the alloy foil. Unexpected time dependences have thus been revealed. (Author)

Lead-acid stationary cells of three types, all with Pb-Ca alloy grids, have been float charged in strings of four or five cells for nearly two years. Individual cell potential differences have been measured during floating at 2.2 V/ cell, during equalisation at 2.35 to 2.4 V, and during periods on open circuit. The potential difference across a cell has been taken as an indicator of its health, following Milner, a high float voltage being preferred to a low one. Three modes of equalisation have been attempted: (i) raising the P. D. of all cells in a string to ca. 2.35 V/cell, (ii) raising the P. D. of one cell in a string to 2.35 V using a second power supply in parallel with that maintaining the other cells at 2.15 to 2.2 V each, and (iii) raising the P. D. of one cell to 2.35 V using a separate power supply, treating this cell in isolation from other cells in the string. Only the last method appears to be without drawbacks.

INTRODUCTORY N0TE.-The affirmation that “science is common sense at its best” has no plainer vindication than the manner in which provision is made by Germany for the care of her insane. Nearly forty years ago the general German public as well as those afflicted with various forms of alienation were fortunate in possessing a man who was well qualified by his intellectual attainments, no less than by his own training for this special duty, not only to formulate a plan for the development of the systematic care of the insane, but also to indicate clearly the scope and the lines along which this work could be carried out with the greatest advantage to all concerned. Griesinger was thoroughly familiar with the remarkable advances that were being made in Germany in all branches of the medical sciences, and his daily life had brought him into immediate contact with the men who were creating a new epoch in the history of medicine. It is a significant fact that three men, Griesinger, Rose and Wunderlich, born within a few years of each other, living on the same street in Stuttgart, and all intimate friends, should have chosen medical careers and that each should have become famous in his own specialty. Each one of the three became in a measure the representative of a new school of medicine. Born in I8I7, Griesinger began the study of medicine in 1834, at the University of T#{252}bingen whence he moved to Zurich. In 1838, he first gave evidence of his interest in the study of insanity by making application for the position of assistant physician in the asylum at Winnenthal. From that time until his death, which occurred in Berlin in 1867, his enthusiasm steadily increased. His

THERE is evidence that in electrolysis of aqueous solutions at mercury cathodes the accumulation of atomic hydrogen dissolved in mercury as an amalgam, as suggested by Heyrovsky1 and Ilkovic2. M¨ller3 re-investigated hydronium ion discharge at dropping mercury electrodes, and attributed long term changes in volume to a slow step in the overall reaction either elimination of hydrogen from an amalgam, or decomposition of aqueous hydrogen molecule ions. The present work confirms that hysteresis is associated with the metal phase. We also present evidence for the occurrence of electrochemical desorption at mercury containing dissolved hydrogen atoms.

On June 29, 1932, a Negro girl, aged 7 years, was brought to the Harriet Lane Home at Johns Hopkins Hospital in an unconscious state and admitted there as a patient. The relatives reported that there had been a sudden onset of convulsions followed by stupor. Far across the city on July 25 another Negro girl, aged 10 years, was admitted to the pediatric service of the Provident Hospital in a stuporous condition, with a history of convulsions and intermittent unconsciousness for the previous four days. These two initial cases were followed by others that resulted in the unraveling of one of the most dramatic and fascinating medical and public health problems of recent years. By September 2, in both sections of the city, a total of forty cases of lead poisoning were discovered, chiefly among children, all in Negro families in which discarded storage battery casings had been used

In hydrogen overpotential measurements on electropolished Pb electrodes in charcoal-cleaned aqueous HClO4, new hysteresis effects, not due to anion adsorption processes, have been observed. Overpotentials changed both reversibly and irreversibly, a substantial increase of electrode activity for hydronium ion discharge occurring in the course of time. Relations developed between overpotentials and the total amount of cathodic charging of the electrode lead to an explanation of the observed effects in terms of continuous accumulation of H atoms at the interface and in the bulk metal. Observed changes in the Tafel slope are consistent with enhancement of the discharge rate as a result of specific adsorption of hydronium ions on H atom-occupied sites on the electrode.

Both the capacity and the potential of a lead cathode increase linearly with the logarithm of the charge passed (10 to 600 C cm–2) in prolonged cathodisation, suggesting that the rate of charge transfer increases linearly with the bulk hydrogen content of the metal.

All the case records of patients with congenital syphilis seen in the Harriet Lane Dispensary of the Johns Hopkins Hospital from its opening in 1914 until June 1934 have been studied, with special emphasis on the end results of treatment. There were 991 patients in all, of whom 621 had early congenital syphilis and 370 the late form. An arbitrary dividing line of two years of age is made between the early and late groups. In the study of the therapeutic results, no patient was included unless he had been followed for at least two years. Many had been under treatment and observation for as long as fifteen years. Babies remain under the care of the obstetric service until they are 2 weeks old, and all patients in the Harriet Lane Dispensary on reaching the age of 15 years are transferred with their records to the adult clinic regardless of