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As a preface to my paper, I wish to acknowledge my indebtedness to the President of this Society, to our last ex-President, to the ex-President of the Ohio State Medical Society present, to Dr. Thomas, Dr. Barnes, Dr. Dickson and all others who have confirmed my diagnoses, watched the results of treatment, or in any way have aided me in my work; and to thank them for their very complimentary remarks in the discussion of my previous papers. Having my work characterized as the greatest discovery of the age by one member, my name associated with that of Jenner by another, and another give expression to his pride that a member of this Society had done what I have; would be exceedingly gratifying to me at any time, but especially just now when I am promulgating ideas which must arouse the indignation of every great medical professor in the world,

A number of simple chromatographic applications are described in which sheet paraffin or other plastic film is used as an adhesive vapor barrier: 1.A funnel attached to a paraffin-enclosed narrow paper wick for spotting large volumes of sample solution as small spots of controlled size.2.A funnel for the elution of a spot and its reapplication to another paper in a single operation.3.A method for elution or chromatography which requires no jars or other rigid saturation chambers.

The selenium content of various types of papers including cigarette papers has been determined. The selenium content of representative tobaccos from different parts of the world has also been determined. Samples were processed by decomposing them by means of the oxygen flask combustion technique. After excess oxygen was eliminated the selenium content was determined by means of the catalytic method of West and Ramakrishna (16). The selenium content of cigarette papers was found to range from 0.87 to 2.11 ppm (as SeO2) while filter papers and newspapers were found to contain from 0.21 to 1.38 ppm. The selenium content of most tobaccos fell somewhere in the range of 0.46 to 1.20 ppm. The Indian crude cigarette (Beedi) was found to contain as high as 4.10 ppm. Discussion of the findings includes some observations on possible health significance of selenium in smoke. Comments are included regarding the hazards of cigarette smoking as compared to those of cigar and pipe smoking.

Reaction of flocculation between the antitoxin ofCl,oedematiens and the corresponding immune horse serum was studied with the aid of precipitation on paper. When toxin and immune serum were placed on the same place on the paper, a flocculate appears, which unlike all the rest of the proteins is not washed off the paper by the veronal buffer. The fiocculate is precipitated at the zone of considerabic surplus of antitoxin. The quantity of precipitate is increased in proportion to the quantity of the added antigen up to the time when the whole quantity of the antigen is precipitated. Then the precipitate begins to dissolve in the surplus of the antigen. Data which were obtained by the method of precipitation on paper correspond to the results of determination of the quantity of the antibodies in the same serum with the aid of the antigen fixed on paper through diazoconnection and the residual haloidalkylate. This points to the possibillity of replacement of the biological method of determination of the antigens ofCl.oedematiens by the immunochemical method.

The penetration of liquid into a piece of filter paper hung vertically above a liquid is studied theoretically and experimentally. The height of the ascent of the liquid is proportional to the square root of the time at the initial stage of the penetration, but the proportionality does not hold in a wide range of time. The equation which describes this relationship between the height and time has been derived. The values of the parameters in the equation have been determined for acetone, benzene, water, carbon tetrachloride and ethanol. It is concluded that the capillary gap in the filter paper is about 6 μ in the half distance and the length of the gap is about 3 times larger than the length of the filter paper, if the gap is assumed to be two dimensional.

Work done during the past twenty years on the physics of fibre bonds in paper and the behaviour of paper under mechanical strain is reviewed. The first major section of the article illustrates the chemical nature of the cohesion in paper and reports the results of direct observations on fibre-to-fibre bonds. A statistical theory of the geometry of fibrous networks is shown to be a basis for the characterization of fibre bonding in paper. The second major section is concerned with the mechanical behaviour of paper. This is shown to be a complex subject because paper exhibits almost every known rheological property. Direct, conventional rheological methods, molecular theories and the concept of elastic networks are discussed in this context. Further complications arise from any changes in the water content of the environment. Such effects are conveniently thought of as a competitive process wherein cellulose and water compete for hydrogen bonds for their hydroxyl groups. Not least among the rheological phenomena that paper exhibits is mechanical fracture. This is a discontinuous process that is found to be intimately connected with the mechanical work done on the specimen and is principally governed by its geometrical distortion.

The electrophoretic mobility of an inosamine in borate buffer is very dependent on configuration, and a set of 10 inosamines showed a wide range of mobilities. The order of mobilities within the set changed as the pH of the buffer was changed in the range 7.7-9.5. Paper electrophoresis in borate buffers can effectively separate mixtures of inosamines. The probable site of reaction between an inosamine and borate ions has been identified for some isomers. In aminodeoxy-scyllo-inositol and 3-amino-3-deoxy-epi-inositol the amino group is involved in the formation of a tridentate borate complex of adamantane-type structure, which is electrically neutral over the above range of pH values. Aminodeoxy-scyllo-inositol simultaneously combines with a second molecule of borate, forming a bis-tridentate complex with one anionic centre. There is evidence that in other isomers protonation of the amino group and formation of anionic borate complexes at hydroxyl groups are not independent reactions. Paper electrophoresis in non-complexing buffers provides evidence for the relative basicities of inosamines. DL-2-Amino-2-deoxy-epi-inositol, which has an interaction between axial amino and hydroxyl group in the preferred conformation, was the strongest base in the set, whereas the bases with an axial amino group free of such an interaction were the weakest. Inosamines form N-carboxyl derivatives in the normal way on exposure to carbon dioxide in the presence of strong alkali.

The filter paper method for measuring soil water potential was evaluated. The method was calibrated using salt solutions, thermocouple psychrometer, pressure plates, and soil columns at equilibrium. The predicted water potential was influenced by the type of contact of the soil with the filter paper. It is suggested that one filter paper be placed beneath the soil (good contact for liquid flow and vapor flow) and one filter paper be placed above the soil not in physical contact (allowing vapor flow only). It was found that the absolute temperature was not too important but temperature variations had a large effect on the predicted soil water potential.

Modified paper chromatography procedures for the analysis of fatty acids produced by anaerobic bacteria are described. Both ethylamine and hydroxylamine derivatives of fatty acids were prepared from inoculated anaerobic culture broth. The derivatives were spotted on chromatography paper and developed with appropriate solvents. Paper chromatography is a valuable alternative to gas liquid chromatography as an ancillary procedure in the identification of anaerobic bacteria in the clinical bacteriology laboratory.

A simple paper chromatographic method for separation and quantitative determination of tetracycline in pharmaceutical preparations was developed. The method is based on the complexation of the antibiotic with a mixture of urea and disodium edetate on a chromatographic paper at pH 7.4. Spots of tetracycline and its degradation products were located under UV light, and their respective Rfvalues were calculated. The method can be used to determine tetracycline phosphate, even in the presence of oleandomycin. The developed method proved satisfactory in monitoring the stability of the antibiotic base and its hydrochloride.

In the Winter 1973 issue of the Journalwas presented a chapter on planning the technical article, part of a projected book on publishing in technical journals and magazines. This particular chapter discusses the organization of the technical paper as distinct from the technical article. It shows the relationship of the paper to the report and compares the practices of several scientific and technical journals.

An attempt has been made to apply the concepts of fracture mechanics to describe the behaviour of a paper sheet with a crack. Considering paper as an orthotropic homogeneous continuum, the critical strain energy release rate, Gc, for eight different papers has been measured using linear elastic fracture mechanics. Also, a direct measurement of work of fracture, R, has been made for these samples by using the quasi-static crack propagation technique. For both techniques, results independent of specimen dimensions were obtained. Gc and R were found to be experimentally equivalent. The fracture toughness of paper has been compared with that of other engineering materials.

AbstractTwo equations are presently used to relate folding endurance to the load on the test strip Neither of these contains the initial tensile strength of the paper as a term, though tensile strength greatly influences folding resistance. An equation is derived which relates initial tensile, load and folding endurance. The three equations are compared using data from Goldberger and Rhyne. Schmidt's equation for the change in tensile strength as folding proceeds is discussed and an alternative relation is given. A unit is suggested for the tensile folding fatigue, TFF, of paper. The effect of paper thickness on folding endurance is considered.

Concentrations of toxic metals can be determined in a drop of blood, such as might be obtained from a finger-prick, by spotting the blood onto filter paper, drying it, and then burning a standard size disc punched from the filter paper in an atomic absorption spectrophotometer. Results for lead, cadmium and zinc determined in this manner compare favorably with accepted macro-methods of analysis. The advantages of this procedure, namely the ease of specimen collection and the simplicity of the analysis, may make this the method of choice in biochemical monitoring for trace metal absorption by workers.

Energy calculations for manufacture of paper from logs and waste papers are reported based on data on energy use from the Canadian Census of Manufactures and estimates for collection and de-inking of waste. The energy requirement of the recycling technology explored exceeds the energy requirement of manufacture from logs by 33%. It appears that forest conservation through recycling has a fossil fuel cost.

Bottom fauna surveys of the Lower Sabine River in the vicinity of Orange, Texas were performed from 1967 to 1969. During this time samples were taken before and after effluent from a black-liquor paper mill was discharge into the Sabine River. Species diversity indices were determined for each station (one station above the discharge canal and four below it). The results obtained indicated that the paper mill effluent was not disturbing the river to a degree that it would cause damage. However, the proximity of Sabine Lake (an estuary) and the very low flow often encountered on the Sabine River makes it imperative that high standards be imposed in treatment of the waste water and that qualified personnel make periodic studies on the river.

Procedures are presented illustrating methods of preparing glass columns (3.5 to 9.9 cm in diameter and 117 to 170 cm in height) packed with powdered paper for chromatography. A reaction mixture of anthranilic acid-l-C14, 3-hydroxyanthranilic acid-l-C14 and 5-hydroxyanthranilic acid-1-C14 was placed on a powdered paper column and the components separated by passing different organic solvent systems through the column. DL-Kynurenine-keto-C14, DL-Kynurenine-ring-2-C14, Hydroxy-DL-Kynurenine-keto-C14, and DL-Tryptophan-7a-C14 were resolved into the pure D- and L-isomers by the use of the powdered paper columns with very little loss of material.

The potential use of waste paper as a feedstuff for ruminants was investigated. Analyses of a range of types of paper showed that waste paper could be regarded only as a source of energy for animal production ; cellulose was the main chemical constituent. Levels of nitrogen (N) and soluble ash were very low in most samples. In vitro organic matter (OM) digestibilities ranged from a mean of 22 per cent for waste newspaper up to a mean of 63 to 65 per cent for high-quality office waste paper and computer printout. Individually penned mature crossbred wethers gained liveweight at a mean rate of 11 7 g day-1 when fed on pellets consisting of 65 per cent Gwernment waste paper (52.5 per cent in vitro digestibility), 32 per cent linseed meal and 3 per cent minerals, provided roughage as chaffed hay (50-300 g head-1 day-1) was fed as well. Mean daily dry matter (DM) intakes were about 1600 g. Without the chaffed hay, intakes fell to 1400 g DM head-1 day-1 and the sheep maintained weight. In a second experiment, crossbred ewes aged about seven months were offered ad libitum either lucerne pellets, Government waste paper pellets, or pellets containing equal proportions of Government waste paper and newspaper. The paper pellets contained 84 per cent paper, 8.4 per cent molasses, 3.6 per cent urea and 4 per cent minerals. During the first seven weeks, when 100-200 g head-1 day-1 of chaffed lucerne hay were offered in addition to the pellets, mean DM intakes (g day-1) and liveweight gains (g day-1) were 1522 and 144 for the lucerne-fed sheep, 950 and 60 for the sheep on Government paper pellets, and 450 and -27 for the sheep on the 42 per cent newspaper pellets. During the next two weeks, lucerne chaff was omitted; the sheep on lucerne pellets increased their mean DM intake and rate of gain, those on the Government waste paper pellets maintained their food intake but lost weight slowly, while sheep on the 42 per cent newspaper pellets reduced food intake and lost weight rapidly (-1 18 g day-1). OM digestibility of both paper diets was 56 to 60 per cent when fed with roughage, and decreased to 55 per cent when lucerne chaff was omitted. Ewes on both paper diets were consistently in negative N balance (-1.3 to -3.2 g N day-1) while those fed the lucerne pellets were in consistent positive balance (+3.3 g N day-1).

Analyses for Co, Zn, and Pb on mixed bed and SA-2 cation exchange resin-loaded paper disks in amounts approaching the theoretical limits of detection were attempted. Based on the results, the definition of limit of detection which requires a line intensity above background equal to three times the square root of the background, using a 10-min count, was modified to the line intensity above background equal to three times the standard deviation of the background counted for 10 min on a series of blank disks. Chemical precleaning of the disks and corrections for paper density were shown to be advantageous for work close to the limit of detection by lowering the background count and reducing the weight-corrected standard deviation.

Many paper products, including newspapers and paper goods used in packaging foods, contain lead. The lead content of newspapers, an important constituent of recycled paper, varies with color of ink, type of printing process, and source of newsprint. Recycled newsprint is richer in lead than virgin newsprint. Lead on or in food packages ranged from 2 to 10,000 ppm, and varied with the quantity of printing and color of ink. Printed packages contained more lead than unprinted material, although some unprinted ones contained up to 58 ppm. The potential for introducing lead into meat and milk by feeding waste paper to ruminants is explored. Negligible amounts of lead are introduced into soils and plants from news-paper mulch.

In the examination of questioned documents, problems involving the source or authenticity of carbon copies may be encountered. The copy presented may have been prepared through the utilization of individual sheets of carbon paper, or it may have been produced through a carbonless paper system. In some cases it may be significant to determine whether the copy was produced in the conventional manner or with a carbonless system and, if the latter, which particular carbonless system was utilized. For these reasons, a study of the carbonless systems currently in use was undertaken.

In essay-type examinations for degrees in British universities, marking customs tend to compress the candidates into a narrow band around the mean. This works especially adversely against those who, in examinations with several papers, achieve excellence in one or more. Often such candidates are awarded only the minimum distinction mark, the effect of which is nullified by aggregation. This is of some consequence in the British system, since the designation of a candidate's examination performance as “First Class,” “Second Class, Upper Division,” etc. is formally made by locating his examination average mark within specified intervals on a percentage scale. Awareness of the possible injustice which this method may cause has given rise to the practice of estimating the “balance of papers,” or considering the “classes” attained by the individual papers in the examination (irrespective of the actual mark), and giving the candidate the benefit of the doubt should he, for example, have a certain number of papers in a class higher than that indicated by his examination average. A classification reached in this way may of course be at variance with that indicated by the candidate's average of marks, and thus introduce an arbitrary element. An alternative method is therefore proposed in this paper. The usual custom is to assume that the marks indicating the various classes should be the same for the degree as a whole and for the individual papers. It would seem preferable first to determine the balance of papers which would be accepted as a claim to a First Class degree (since it is unlikely that a candidate writing several papers will be able to attain a first class mark in all) and deduce therefrom the classification intervals for the individual papers. A method of doing so is elaborated.

The even-numbered C2–C22saturated and the C18-unsaturated fatty acid esters of beta- and gamma-sitosterol, stiginasterol, ergosterol, stigmastanol, and gamma-sitostanol were used separately and in model mixtures for the evaluation of existing and the development of new paper chromatographic methods for the separation and identification of these compounds. Satisfactory separations of the esters were obtained by the ascending reversed phase chromatography on cellulose or glass fiber paper using one of the following systems depending upon the number of carbon atoms in the fatty acid moiety of the ester: C2–C12, aqueous acetic acid/chloroform/paraffin oil; C8–C18, aqueous propionic acid/paraffin oil; C8–C22, acidified aqueous methanol/chloroform/paraffin oil or aqueous butyric acid/paraffin oil. The rate of migration of the esters was inversely proportional to the molecular weight and was increased by the introduction of unsaturation.The increased movement due to unsaturation has been correlated with the number of ethylenic hydrogens, and the possibility that polarity of these atoms might account for this phenomenon is discussed. The reversed phase paper partition chromatography of sterols as their esters is suggested as a potential tool for evaluation of polarity of the various attributes of the sterol nucleus in terms of the chain length of the ester fatty acid. The rule of independent contributions of the constituents of a molecule to its distribution isotherm was observed not to hold in this fatty ester series.

An application of the biuret reaction to the determination of protein fractions on filter paper electropherograms of serum is described. The relative mobilities of the serum protein fractions of the domestic fowl and of man are compared. Values are reported for serum protein fractions as separated by filter paper electrophoresis in a methanolic veronal buffer. Some observations on the serum proteins of the estrogenized immature pullet are reported; and it is tentatively suggested that another fraction as well as serum phosphoprotein appears in the serum of the pullet as a consequence of treatment with estrogen.

Non-destructive neutron-activation analysis is used for determining chlorine in paper-pulp. Numerical data have been obtained for bleached and unbleached paper-pulps of different types and origins. The sensitivity of this method is 100 ppm for an irradiation time of 30 min and a neutron flux of 6 × 1010neutrons.cm−2.sec−1and 10 ppm for an irradiation time of 1 min and a neutron flux of 2 × 1012neutrons.cm−2.sec−1. In both cases the amount of chlorine that can be determined depends on the presence of the interfering elements manganese and sodium in the paper-pulp. The time required for a complete analysis, after irradiation, is 5 min.

In the paper which I communicated to the Royal Society in 1881, I presented the results of experiments made at various periods during the preceding five years, and the conclusions which I was then able to found upon them. These conclusions, which are set forth in full in the closing pages of my paper (‘Phil. Trans.,' 1882, Part 1, p. 1) may be shortly stated as follows:—If by proper means the electrical relation between opposite points of the upper and under surfaces of the leaf of Dionœais investigated while the leaf is "excited" either by touching one of its sensitive filaments or by passing an induction current through the opposite lobe, it is found that the excitation is followed after a few hundredths of a second by a sudden electrical disturbance of less than half a second duration, in which the under surface becomes negative to the upper; and that this is succeeded towards the end of the first second after the excitation by a change of less intensity, but of longer duration and opposite sign. From the character and relative durations (time relations) of these changes, which together, constitute what may be conveniently termed the "excitatory disturbance” or “response,” it was concluded that the first was of the same nature with the "excitatory variation” or “action current” of animal physiology, and must be regarded as the expression of a molecular change similar to that which occurs in nerve, muscle, or the electrical organ under analogous conditions. As regards the second, which was designated the "after effect,” it was observed first that it was present only when the leaf was "fresh,” that is, had not been excited immediately before; and, secondly, that it was associated with the previous and subsequent electrical state of the two "led off” surfaces in such a way that each excitation appeared to leave behind it what might be described as a lasting remainder of the after effect, that is, a permanent and homonymous difference of potential: in other words, that each excitation tended to make the under surface relatively morepositive if it were before positive, lessnegative if it were before negative; and that, if the leaf were subjected to repeated excitations, it generally happened that the lasting electrical relation between opposite points of its upper and under surfaces underwent a gradual change, that is, the under surface became more positive the longer the observation was continued. It was further observed that in any leaf a similar modification could be brought about much more rapidly by leading through the explored part a very weak voltaic current in the direction of the after effect, that is, from the upper to the under surface.

The fundamental principles and methods of the sensitometry of photographic papers established by Jones, Nutting, and Mees in 1914 are reviewed. The necessity for the use of intensity scale exposure rather than the older time scale methods is shown.An account of the evolution of the design of an optical wedge sensitometer to fulfill the required sensitometric specifications leads to the description of a new instrument used in this study of the sensitometric characteristics of photographic papers. Details of the complete sensitometric process are given. The resultant characteristic curves from the different types and grades of papers are described and interpreted. The typical characteristic curve of modern papers is discussed and a revised method of determining numerical values, which describe the curve for practical purposes, is given. The new interpretation of the shape of the shoulder region of the curve is significant with respect to the quality of tone reproduction. The new group of characteristic values—speed, maximum gradient, exposure scale, maximum density, and contrast—is defined and discussed. Numerical values obtained by the new sensitometric method are given in tabular form for most of the current types and grades of photographic papers.

Paper chromatography has been found to be a very satisfactory method for the separation of glycerine from hexitols, pentitols, tetritols, and glycols. After separation of the glycerine on paper the glycerine is eluted from the indicated zone with water. The formaldehyde, which is a product of periodic acid oxidation, is determined colorimetrically. A suggested procedure and the results of the analyses of standard glycerine and polyhydric alcohol mixtures are presented in this paper. The results indicate that the glycerine content of the mixtures (glycerine content ranging from 15% to 100% glycerine) may be determined with an average relative precision of 0.7% and with an average recovery of 101.0%.

Both paper and author (D. R. McNeil, (1968)) will be referred to below as DRM. The said paper deals with the following situation: an intersection is controlled by a traffic light with a fixed cycle time, T; the possibility of other delays, e.g., due to turning vehicles, is ignored; arrivals at the light form a compound Poisson process; if vehicles arrive to find the light green and the queue empty they are not delayed, while in the contrary case they depart when they reach the head of the queue, providing the light is green, each vehicle taking a constant time to move off. The length of the effective red period is R. For further details and discussion, DRM may be consulted.

It has been proved by Pepis that any formula of the first-order predicate calculus is equivalent (in respect of being satisfiable) to another with a prefix of the formcontaining a single existential quantifier. In this paper, we shall improve this theorem in the like manner as the Ackermann and the Gödel reduction theorems have been improved in the preceding papers of the same main title. More explicitly, we shall prove theTheorem 1. To any given first-order formula it is possible to construct an equivalent one with a prefix of the form(1) and a matrix containing no other predicate variable than a single binary one.An analogous theorem, but producing a prefix of the formhas been proved in the meantime by Surányi; some modifications in the proof, suggested by Kalmár, led to the above form.

Whenever possible, one-phase solvent systems, made up of the minimum number of constituents, should be used for paper chromatography. Two-phase systems should be replaced by their equivalent one-phase mixtures giving stability, accuracy, and simplicity. A “phase diagram” of the type shown is required for all commonly used three-component paper chromatographic solvent mixtures to facilitate the design of one-phase solvents for particular problems. Mixtures of n-butanol, glacial acetic acid, and water were studied with this concept in mind.

Conclusions: In spite of significant increases in yield of potatoes from the use of mulch paper, its use on a commercial scale is not likely because of the cost of the paper. The paper used in this experiment cost at retail $7 a roll of 300 linear yards or at the rate of over $100 an acre. Even though it could be bought in large quantity at half this cost, the difference between this and the value of the increased crop at 40 cents a bushel would still be in favor of cultivation. The average cost per acre of cultivating potatoes on 100 western New York farms in 1931 was $6.75. Under present methods of applying mulch paper, the saving in cost of cultivation would be far more than outweighed by the cost of applying the paper.

Abstract: A Chromatographic method for the separation and detection of copper, nickel and cobalt by extraction with organic solvent mixtures on stripes or sheets of adsorbent paper is described. The paper, after absorption has taken place, is sprayed with a solution containing suitable reagants for detection of the ions, whose presence is indicated by the appearance of characteristic coloured bands. The following metals have been separated: copper, nickel and cobalt; the metals were present as sulphates and the chromatograms were developed with different solvents to study their effect on the Rf values. After evaporation of the solvent, the strip was sprayed with a solution of rubeanic acid in ethyl alcohol and exposing them to ammonia gas, copper gave an olive green band, nickel a violet blue and cobalt an yellowish brown band.

Summary: A reproducible paper chromatographic procedure has been developed for resolving a mixture consisting of 1-mono-, 1,3-di-, and triglycerides, cholesterol, and cholesteryl esters. The separation is accomplished, using silicic acid impregnated glass fiber filter paper as the chromatographic medium and various ethyl ether-isooctane mixtures as the solvent systems. A reagent consisting of 1:1 concentrated sulfuric acid: water has been introduced for visualizing the lipides on the chromatogram and for distinguishing between glycerides and cholesterol-containing lipides. Unsaturation in the fatty acid moiety of the mono-, di-, and triglycerides had no detectable effect on the Rf values of these substances. Fatty acid chain length did not affect the Rf of the cholesteryl esters with the solvent systems studied. Increasing the percentage ethyl ether in the solvent system caused an increase in the Rf values of each lipide not moving at the solvent front.

Summary: Paper chromatography has been found to be a very satisfactory method for the separation of glycerine from hexitols, pentitols, tetritols, and glycols. After separation of the glycerine on paper the glycerine is eluted from the indicated zone with water. The formaldehyde, which is a product of periodic acid oxidation, is determined colorimetrically. A suggested procedure and the results of the analyses of standard glycerine and polyhydric alcohol mixtures are presented in this paper. The results indicate that the glycerine content of the mixtures (glycerine content ranging from 15% to 100% glycerine) may be determined with an average relative precision of 0.7% and with an average recovery of 101.0%.

Summary A modified extraction method has been developed for the determination of the moisture content of insulating papers used in condensers and transformers. The water is extracted from the paper sample with methanol continuously titrated with Karl Fischer reagent by means of the special apparatus devised. The method can advantageously be used to measure the adsorption isotherms of paper samples containing 0.05–2 % water.

By use of a strongly basic anion-exchange resin paper in the hydroxide or carbonate forms, caesium 137 can be separated from irradiated uranium solutions on a ring oven. A ring oven separation of caesium 137 from irradiated thorium can also be achieved by using an oxalate-hydroxide form resin paper. In each case the caesium 137 is washed to the ring zone with water and determined byγ-ray spectrometry. The coefficient of variation of the methods is less than 2 per cent. Mit einem stark basischen Anionenaustauschpapier in der Hydroxid- oder Carbonatform kann137Cs aus bestrahlten Uranlösungen auf einem Ringofen abgetrennt werden. Mit einem Oxalat-Hydroxid-Harzpapier läßt sich137Cs auch von bestrahltem Thorium auf einem Ringofen trennen. In beiden Fällen wird137Cs mit Wasser in die Ringzone gespült und durchγ-Strahlspektrometrie bestimmt. Die Methoden unterliegen Abweichungen von weniger als 2%. Par l'emploi d'un papier échangeur d'anion sous forme hydroxyde ou carbonate, le césium 137 peut être séparé de solutions d'uranium irradié au four annulaire. On peut aussi séparer, au four annulaire, le césium 137 du thorium irradié, avec un papier résineux sous forme hydroxyde-oxalate. Dans chacun cas, le césium 137 est chassé vers la zone annulaire par de l'eau et déterminé par spectrométrieγ. Les méthodes peuvent fournir une précision meilleure que 2 pour cent.

Summary TheRf values of representative amino acids are significantly affected by the width of narrow strips of paper as well as by nearness of the sample to the edge of wide sheets. Amino acids with high, low, and intermediate isoelectric points were used in the study. The Rf values increased significantly in all instances if either the rectangular paper strip was made very narrow or the amino acids were placed near the edge of a sheet of paper. This effect was obtained with a basic solvent as well as with an acidic one.

This paper documents vegetation injury caused by SO2 emissions from a sulphite pulp and paper mill located in Ontario. Acute vegetation injury caused by SO2 was correlated with increased levels of S within injured vegetation, meteorological data, and air sampling records of SO2 monitored by a continuous recorder located adjacent to the vegetation injury zone. The symptoms of injury observed on plants within the injury zone were described, and the relative sensitivity to SO2 was determined for 75 plant species in the area.

The chromatographic behavior of 14 metal ions with aqueous-organic wash liquids on ion-exchange papers is compared with results in columns and thin layers of the same resin. It is shown that many column separations can be obtained on paper, and that paper chromatography can often be used to preevaluate systems for separations on columns. The mechanism for the chromatographic processes and differences between techniques employed with columns and papers are discussed.

A velocity-independent plate-height term comparable to eddy diffusion has been described for paper chromatography. This term couples with nonequilibrium lateral diffusion and is a major contribution to zone spreading at high solvent velocities. A mechanism is proposed based on random variations in Rf values caused by the inhomogeneous structure of paper. On theoretical and experimental bases it is demonstrated that maximum resolution in paper chromatography can be obtained by control of solvent velocities to values near 1 ± 10-3 cm/sec.

TODAY THE THESIS requirement in higher education is an accepted academic tradition. Despite an absence of controlled studies about its efficacy, few seem to take issue with its validity. In the medical school this "ultimate obstacle" has been distilled by many departments into a "term paper requirement." Not uniformly perceived as a relished opportunity by all medical students, here too, educational effectiveness has yet to be documented. The following report describes how in the Department of Pediatrics at the Ohio State University College of Medicine a long-standing term paper requirement was modified to accomplish specific objectives providing both subjective and objective evidence concerning the efficacy of modification. The techniques are seen as having somewhat broader implications. BACKGROUND In early 1950's, a number of pediatric departments began encouraging their students to seek out the overall impact of disease upon a child, his family, and his community. Concurrently, attempts to kindle in-depth

The meeting will be held July 30-August 3, 1967, at the University of Nevada, Reno, Nevada. Abstracts are included for papers to be presented in full and those to be read by title. The author presenting the paper is indicated by an asterisk. Where a number is missing the abstract was withdrawn or failed to qualify for publication. Publication deadlines do not allow thorough proofreading of abstracts by the Editor.

Investigations of paper-fiber sludge deposits in the Rainy River, Minnesota, below paper mills were made to determine water characteristics over them with reference to survival of walleye (Stizostedion v. vitreum) eggs and fry and occurrence of bottom fish-food organisms. Sampling of water from the fiber-sludge water interface to the surface showed gradients in oxygen as great as 0.1 ppm to near saturation, and in dissolved sulfides from 0.8 to 0.0 ppm. The most rapid gradient of these materials was in the bottom 20 mm. Levels of sulfides were most affected by current velocity and showed little relation to temperature or season. Walleye eggs placed in test trays on fiber mats had lower survival than those placed 12 inches above the mats and those placed on mineral substrates. Eggs and fry placed on mats died within 48 hours. Laboratory bioassays showed that sulfide levels of 0.3 ppm under controlled conditions approximating river conditions were acutely lethal to Gammarus pseudolimnaeus and walleye eggs and fry. Fiber released from paper mills forms sludge mats as far as 62 miles below outfalls and creates oxygen deficiencies and H2S concentrations near the sludge-water interface that are lethal to early life history stages of fish and some fish-food organisms.

Several statements and conclusions in the recent paper on diapause in the cabbage maggot by McLeod and Driscoll (1967) are quite misleading and require clarification. In my paper (1965), I was not in a position to critically appraise the results of earlier workers and I therefore simply presented my data as factual information. In their paper, McLeod and Driscoll present data to support the findings of earlier researchers in England, France, and Russia and they concluded that these records did not agree with the results of studies at Charlottetown. The disagreements were obvious but McLeod and Driscoll give no valid explanation as to why the results were different.

1.False-positive tests for glycosuria using Benedict's test were found in 30 of 40 patients receiving antituberculosis drug therapy with isoniazid, para-aminosalicylic acid and streptomycin, in a range of trace to two plus.2.None of the patients had false-positive reaction for glycosuria using a specific enzyme impregnated test paper (Tes-Tape).3.The use of enzyme impregnated testing paper is recommended for the routine determination of glycosuria in patients receiving the present day commonly used antituberculosis drugs. It appeared sufficiently accurate in detecting true glycosuria when compared with Benedict's reagent in testing urines with known concentrations of glucose.

A quantitative paper chromatographic method has been developed which is used routinely as a stability assay for estrogenic hormones in anabolic vitamin tablets. The method involves (a) extraction of the estrogenic hormone into ether from an alcohol-water suspension of the ground tablets, (b) clarification of the extract by chromatography on an alumina column, (c) paper chromatographic separation of the estrogenic hormone present in the column eluate from interfering degradation products, (d) location of the estrogenic hormone on the chromatogram by the guide strip technique employing a chromogenic agent, (e) elution of the estrogenic hormone from the chromatogram, and (f) quantitative spectrophotofluorometric analysis of the eluate. Recoveries in excess of 95 per cent are obtained by chromatographing simultaneously replicates of standard and sample solutions on the same chromatogram. A detailed account of the procedure is presented using the assay of ethinyl estradiol in concentrations of 0.0014 per cent in anabolic vitamin tablets as an example.

A paper chromatographic method for the quantitative separation and determination of oxytetracycline in the presence of its degradation products is presented. The separation of the antibiotic was carried out by making use of its complexation with urea on the chromatographic paper. Oxytetracycline and its degradation products gave characteristic fluorescence under UV light, and their respective Rfvalues were given. The recovery of this method was satisfactory (mean deviation = −3.0%) and was sucessfully applied to the assay of oxytetracycline in bulk and other pharmaceutical dosage forms. Hydrocortisone acetate and polymyxin B sulfate did not interfere with the chromatographic separation.

The ideal technique for abstracting medical papers is contained in the “PMRC” formula which calls for the purpose (P), methods (M), results (R), and conclusions (C) of the research or clinical observations to be stated in 200 words or less. This formula is a useful framework to help writers prepare more substantive abstracts. By selecting keywords and the significant findings, and by stating in concrete terms, succinctly and accurately, the four parts of the formula, one builds the abstract directly from the paper. A reader, author, professional abstractor may use the formula, although the techniques and application may vary in steps for completeness and refinement. Notes taken by the reader serve as an instrument to facilitate recall. The formula provides a framework for comprehensive, well constructed abstracts for writers. The PMRC formula is an effective pattern for writing abstracts which are more informative, concise, and valuable than abstracts without these four parts distinctly present, are not interchangeable with summaries, and can stand alone without the entire article. One argument against an abstract—it is not the whole original paper.