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A new solvent system, to avoid the use of phenol—water, has been developed for the chromatography of complex mixtures of intermediary metabolites.The solvent contains ethylenediaminetetraacetic acid, ammonia, water, isobutyric acid and four simple aliphatic alcohols, and is stble at least for many weeks. The advantages and properties of this solvent are discussed, and the mobilities in it of aobut one hundred metabolic intermediates are listed with reference to the mobility of aspartic acid. It has been found that the chromatographic resolution and the sharpness of the spots are greatly improved by the use of papers other than Whatman No. 4. WhatmanNo. 2 is distinctly superior to Whatman No. 4, but the best results have been obtained with Ederol No.202 (J.C. Binzer, Vertriebs-G.m.b.H., Hatzfeld/Eder, West Germany). With these papers the solvent development times are about 30 h for semi-stench and 18 h for n -butanol—propionic acid—water.

Fibrous holocellulose pulps were prepared in approximately quantitative yield from flax shives and wheat, oat, and fiber flax straw that had been macerated in a buhrstone mill and delignified by sodium chlorite. Paper hand sheets that were formed from pulps subjected to prolonged beating were glassinelike in character. Strength of all straw holocelluloses developed slowly on beating. All papers had relatively low densities compared with the usual values for papers from wood pulps. Tear resistance was initially low for all straw holocelluloses, especially flax shives, and decreased with beating. Color reversion, due almost entirely to light, was rapid in all test sheets. Possible uses for straw holocellulose papers are suggested, although, at present, the process is too expensive to be commercially feasible.

The authors have determined the mobilities of haemoglobins by comparing the electrophoretic migration of haemoglobin and serum proteins on paper strips. The accuracy of the measurements is of the order of a few per cent. Therefore, these measurements can be helpful in identifying haemoglobins.

Paper chromatographic procedures may be used to detect cephalothin and its metabolite desacetylcephalothin in urine, plasma, synovial fluid, and cerebrospinal fluid. Protein-bound antibiotics are released from plasma, cerebrospinal fluid, and synovial fluid by dilution with an equal volume of dimethylformamide. Data are presented on the sample preparation, paper chromatographic system, and other specific techniques.

A quantitative paper electrophoresis method for the separation of haemoglobins A and A(2) is described. The possible sources of error and the accuracy of the method have been investigated. The normal range for haemoglobin A(2) by this method is 1.3% to 4.3% of the total haemoglobin concentration. Good clinical correlation has so far been obtained.

Insulin travels as well defined band in electropherograms if acetic acid-water 1:2 (v/v) is used as a buffer. Preparations of partially acetylated insulin were analysed by this method. From the results it could be derived that the molecular weight of insulin is 6,000. An improvement in the amino-nitrogen determination of insulin is described in the experimental part. Résumé L'insuline se déplace sous forme d'une bande bien défine des électropheérogrammes lorsqu'on utilise comme tampon un mélange acide acétique-eau 1:2 (v/v). Des préparations d'insuline partiellement acétylée ont été analysées par cette méthode. Les résultats permettent d'attribuer à l'insuline un poids moléculaire de 6,000. Dans la partie expérimentale, on décrit une amélioration du dosage de l'amino-N de l'insuline. Zusammenfassung Insulin wanderte als ein genau begrenzter Streifen in einem Elektrophoregramm, in dem eine Mischung von Essigsäure-Wasser 1:2 (v/v) als Puffer verwendet wurde. Präparate, die aus teilweise acetyliertem Insulin bestanden, wurden mit Hilfe dieser Methode analysiert. Aus den Ergebnissen wurde gefolgert, dass das Molekulargewicht des Insulins 6,000 ist. Im experimentellen Teil wird eine verbesserte Bestimmungsmethode für Aminostickstoff im Insulin beschrieben.

A detailed study of various reversed phase systems for the qualitative analysis of fatty acids has been made and it has been shown, among other things, that the liquid paraffin-aqueous methanol system is a most convenient one. The details of a fairly simple and rapid method for the quantitative estimation of higher fatty acids have also been discussed.

Lüzuci, sıkıştınlamaz ve homogen bir akışkanın hareket dife- rensiyel denklemleri lineer değildirler* Bu yüzden onların genel çözümlerini bulmak çok güç ve hattâ imkânsızdır. Araştırıcılar ya özel tarzda çözümler bulmakla iktifa ederler veya çözümü sadeleştirici bazı kabuller yaparlar.

A number of Cepheid variables in the small and in the large Magellanic cloud are analysed. The light curves used are those published by H. Shapley and his associates.

Some measurements on the permeability of various types of building papers to water vapour are reported, with a short discussion of the efficiency of the various papers as vapour barriers.

In this paper clusters are considered, which contain a few variables only. Not in ali instances are the periods equally well determined.The inclusion of these clusters is valuable because they contain several 8 Cepheî stars. The results of the analysis are tabulated and^are" graphically represented in a figüre. The principal features of this'figure*’are”discussed.

The development of a reagent-impregnated paper strip test for niacin is described. The test system is based on the formation of cyanogen chloride by the reaction of chloramine-T and potassium thiocyanate in the presence of citric acid. Rupture of the pyridine ring of niacin by cyanogen chloride yields γ-carboxy glutaconic aldehyde and coupling with a primary aromatic amine produces a yellow color. Sensitivity to niacin, both in known solutions and from extracts of 378 clinical mycobacteria isolates, equalled or exceeded that of other methods for detection of niacin. Correlation with other tests for mycobacterial niacin was excellent.

A notable advance in knowledge may raise as many questions as it solves, and a period of intensive and fruitful research may at first sight seem to leave us as far as ever from the solution of the problem we are in vestigating. This might plausibly be said of poliomyelitis. Few affections of the nervous system have been more closely or successfully studied within the past few years, yet fresh pathological and epid?miological factors appear for elucidation, effective therapy remains as remote as ever, and many of our earlier certitudes have gone by the board. Yet we must necessarily be nearer a grasp of the many problems presented by poliomyelitis, and the present time is appropriate for a review of some recent advances in our knowledge. A comprehensive summary of these is not possible within the limits of my present opportunity, and I propose, therefore, to confine myself to a brief consideration of the question of the specific treatment of the disease in the light of our rapidly changing conception of its nature. By way of definition we may say that poliomyelitis is one of a small group of infections of the nervous systems due to the action of ultra-microscopic viruses, the morpho logical identities of which are unknown to us. Other examples of the group are epidemic encephalitis and rabies, and in all three it is the grey matter which is the point of attack, whence these viruses are spoken of as " polioclastic." Of the characteristics they have in common perhaps the most striking are that they multiply only in contact with the living cell, within which their life and activity appear to be very brief, for after a short period they disappear. To this disappearance the name " auto-sterilization " has been applied, and in consequence of it virus diseases may be spoken of as " self-limiting."

A very com plete study of the light curve of th e irregular cluster type sta r A R. H er has been made by J. Balâsz and L. D etre. The light curves published by these authors have been analysed by the m ethod of the autocorrelation function and subsequent power series. In th e diagram log P: A(2), the variable falls in the norm al region of th e irregular Systems, but during the secular changes of th e light curve the point A(2) sh ifts up and down in the correlation plane.