bluuebunny/crossref_metadata_2025 huggingface dataset:
ADAPTATION OF THE METHOD OF LOWRY AND LOPEZ TO THE ESTIMATION OF INORGANIC AND ORGANIC PHOSPHATE IN PLANT EXTRACTS
Authors: Waygood E. R.
Published: April 2011

The method of Lowry and Lopez using ascorbic acid as the reducing agent with the Fiske–Subbarow reagents at pH 4.0 is proposed for the estimation of phosphate in plant extracts. The method has been reinvestigated with respect to its adaptation to the Coleman Universal spectrophotometer, Model 14, to suitability of wave length, pH range, reagent concentration, rate of reaction, color stability, and the effect of silicate. The experiments, in general, confirm those of Lowry and Lopez. A wave length of 650 mμ has been employed. No blue color is formed in the reagent blank between a pH of 3.1 and 4.2; accordingly a pH of 4.0, maintained by a sodium acetate – acetic acid buffer, has been used. A concentration of 0.25% ammonium molybdate and 0.1% ascorbic acid has been shown to be optimum for maximum color development in concentrations of phosphate up to about 25 μgm. P in the final volume. The reduction of phosphomolybdic acid is complete in about five minutes, and the method is characterized by a high degree of color stability. Silicate interferes with the reaction. Where the plant has a liberal silicate economy the cell wall material, with which the silicon is associated, must be removed from the extract. The method has been applied to the estimation of phosphate liberated from organic combination by hydrolysis for specified times in 1 N hydrochloric acid. Total phosphate is estimated by wet ashing with 60% perchloric acid. Recovery tests of known amounts of inorganic phosphate and glucose-1-phosphate added to wheat leaf and seedling extracts give an absolute error within 2%, which is considered permissible. A balance sheet of phosphate fractions in the supernatant, residue, and whole juice of wheat leaves is discussed.
THE ANATOMY OF MONODONTOMERUS DENTIPES BOH., AN ENTOMOPHAGOUS CHALCID
Authors: Bucher Gordon E.
Published: April 2011

The anatomy of the adult of Monodontomerus dentipes Boh., a chalcid parasite of sawfly cocoons in Europe and America, is described. An attempt is made to homologize the structures of this highly modified insect with those known in more generalized insects, in the hope of clarifying some questions of chalcid morphology which has been generally neglected by entomologists. The nomenclature employed is of a kind generally acceptable to students of morphology, an effort being made to eliminate the use of terms specific to a limited group of insects. The anatomy of Monodontomerus is not widely different from that of phytophagous chalcids described by other authors.
A PRELIMINARY ACCOUNT OF THE BITING FLIES AT CHURCHILL, MANITOBA
Authors: Twinn C. R. , Hocking B. , McDuffie Wm. C. , Cross H. F.
Published: April 2011

The occurrence is recorded at Churchill, Manitoba, of 5 genera and 11 species of Cuhcidae, 2 genera and 12 species of Simuliidae (3 and possibly 4 of which may be new to science), and 2 genera and 10 species of Tabanidae. Data are presented on their habitats, life histories, habits, species association and succession, and relative abundance and distribution. Observations on the relationships of these insects to other organisms are recorded, including notes on their status as pests and their influence on human activities in the locality. Evidence is presented that female mosquitoes feed on the nectar of flowers and are efficient pollinators of northern orchids. A brief general picture of the ecology of the locality is given; also details of weather conditions during the period of the survey, and some microclimate data. Illustrations from photographs showing typical habitats of many of the species dealt with are included.
FLUORESCENCE MICROSCOPE EXAMINATION OF TRYPANOSOMES IN BLOOD
Authors: Strugger S.
Published: April 2011

With acridinorange it is possible to stain selectively trypanosomes in blood intra-vitam. In subsequent examination by means of a fluorescence microscope only leucocytes and trypanosomes are visible (as shining bright green bodies), while the erythrocytes are not visible. Living and dead trypanosomes, too, may be distinguished in this way.With the fluorescent dye auramine, trypanosomes in blood may be selectively stained (showing up in golden fluorescence) so that diagnosis for trypanosomes is very greatly facilitated. Even in difficult cases a decision on the presence of trypanosomes in blood is possible.
FAT ABSORPTION AND LUNG OIL
Authors: Weld C. B.
Published: April 2011

The lungs of normal animals and of normal animals fed with oil have been examined for the presence of oil. Frozen sections stained with Sudan IV and haematoxylin reveal Sudan stained intracellular granules and interstitial or intravascular oil globules in alveolar walls. In general these oil globules are larger and more numerous in the oil fed animals than in the normal controls. In the lungs of a considerable number of the animals absorbing fat, patchy areas of oil are found that resemble pulmonary fat embolism. Evidence is presented to show that the finding is neither a histological artefact, nor is it due to oil aspiration. Lung fat determinations give values higher in lungs showing marked oil deposits, but as a rule they remain within the normal range.
THE OXIDATION, IGNITION AND DETONATION OF FUEL VAPORS AND GASES: V. THE HYDROGEN ENGINE AND THE NUCLEAR THEORY OF IGNITION
Authors: King R. O. , Wallace W. A. , Mahapatra B.
Published: April 2011

It should not be possible, according to the nuclear theory of ignition, stated in Part IV, to obtain ignition in the body of a gaseous combustible mixture by any method of heating if it remain truly homogeneous while the temperature is raised. Such mixtures cease to be homogeneous when heated by sudden compression to the temperatures required for ignition because of the formation of finely divided carbon by pyrolysis of lubricating oil or of hydrocarbon vapor. The finely divided carbon provides nuclear centers of ignition in the gaseous mixture. Ignition due to finely divided carbon produced by pyrolysis of the lubricant is demonstrated by experiments with hydrogen as the fuel for a C.F.R. engine. The usual pre-ignition and severe knocking were obtained when the engine in normal condition was run on hydrogen, and it was impossible, as previously found by others, to use any but weak mixtures even at low compression ratios. When however the combustion space was decarbonized and thereafter maintained reasonably clear of fluffy carbon, hydrogen could be used as the sole fuel at any compression ratio up to the limit of 10:1 possible with the engine, and at any mixture strength ranging from very weak to very rich, while power output varied accordingly. Conversely pre-ignition and combustion knock reappeared when carbon dust was admitted with the combustible mixture.
THE FP-54 AS A STABLE VOLTAGE AMPLIFIER
Authors: Seaton N. T.
Published: April 2011

A very simple method is given for operating the FP-54 Pliotron as a stabilized voltage amplifier with a grid current of less than 10−17 amp. The application of the method in the construction of a compact portable electrometer is discussed briefly.
ORGANIC REAGENTS FOR PLATINUM METALS: I. THE DETERMINATION OF PALLADIUM WITH 1,10-PHENANTHROLINE
Authors: Ryan D. E. , Fainer P.
Published: April 2011

Palladium may be precipitated quantitatively with 1,10-phenanthroline from palladous chloride solutions; variations in the hydrochloric acid concentration from 1 to 20% had no effect on the precipitation. The reagent yields no precipitates with other platinum metals under similar conditions; slightly high results, however, were obtained when palladium was precipitated from solutions containing these metals. The precipitate has the composition C12H8N2PdCl2 and may be used as a weighing form for palladium. A micro-volumetric method for palladium using 1,10-phenanthroline is described. Small amounts of platinum (as Pt+4) do not interfere.
REFRACTIVE INDEX OF HYDROGEN PEROXIDE SOLUTIONS. A REVISION
Authors: Giguère Paul A. , Geoffrion Pierre
Published: April 2011

Values for the refractive index of aqueous solutions of hydrogen peroxide reported some years ago by the senior author have been found in error by more than the estimated accuracy of measurements. The error is proportional to the concentration of the solutions and amounts to about 5 × 10−4 for the pure peroxide. More accurate data have now been obtained by using an instrument of higher precision and by refining the analytical method. In addition, some anhydrous hydrogen peroxide has been prepared; its refractive index at 25 °C. was 1.40672 ± 0.0001 with an average temperature coefficient of 3.4 × 10−5 per degree.
COMPRESSIBILITY OF GASES AT HIGH TEMPERATURES: I. METHODS OF MEASUREMENT AND APPARATUS
Authors: Schneider W. G.
Published: April 2011

Methods and apparatus used for compressibility measurements of gases in the temperature range 0° to 600 °C. are described. A further method which can be used at temperatures above 600 °C. is also described. Data for some measurements with pure helium at 0° and at 600 °C. are given, from which the values (in Amagat units), 0.527 × 10−3 per atm. ± 0.003 × 10−3 and 0.439 × 10−3 per atm. ± 0.005 × 10−3 were obtained for the second virial coefficient at 0° and 600 °C. respectively.
THE ULTRAVIOLET ABSORPTION SPECTRA OF SOME CARBOXY DERIVATIVES OF NAPHTHALENE
Authors: Hirshberg Y. , Jones R. Norman
Published: April 2011

The ultraviolet absorption spectra of a variety of naphthalene compounds containing phenyl and carboxy substituents are described. The majority of the compounds contain either the naphthalene-1,2-dicarboxylic acid anhydride or the naphthalene-2,3-dicarboxylic acid anhydride ring systems. It is shown that in ethanolic solution the spectra of these anhydrides change over a period of a few hours. The spectra of the anhydrides in n-heptane or dioxane solution do not change on standing. The effects of the various substituents are discussed in terms of steric inhibition of resonance and of antagonistic and reinforcing actions of the substituents, dependent on the position of substitution. The significance of these data are considered in relation to the general problem of the interpretation of the ultraviolet absorption spectra of complex molecules.
NITROLYSIS OF HEXAMETHYLENETETRAMINE: III. PREPARATION OF PURE CYCLONITE
Authors: Brockman F. J. , Wright George F , Downing D. C.
Published: April 2011

All Cyclonite prepared by nitrolysis of hexamethylenetetramine has been found to contain 1,3,5,7-tetranitro-1,3,5,7-tetrazacycloöctatie (HMX). This impurity is not present in Cyclonite prepared by oxidation of 1,3,5-trinitroso-1,3,5-triazacyclohexane. The oxidation yields 1-nitroso-3,5-dinitro-1,3,5-triaza-cyclohexane as an intermediate. There seems then to be a difference in reactivity of two of the three aza linkages in triazacyclohexanes.
THE NITROLYSIS OF HEXAMETHYLENETETRAMINE: IV. SYNTHESIS OF A CYCLONITE HOMOLOGUE
Authors: Wright George F , Myers G. S.
Published: April 2011

A homologue of Cyclonite has been prepared. This homologue, 1,3,6-trinitro-1,3,6-triazacycloheptane was formed by nitrolysis of methylene-bis-3,6-dinitro-1,3,6-triazacycloheptane, which was synthesized from N,N′-dimethylol-1,2-dinitraminoethane, formaldehyde, and ammonia. The reliability of this synthesis was established by analogous reactions. The nitrolysis yields also 1,8-diacetoxy-2,4,7-trinitro-2,4,7-triazaöctane via 1-acetoxymethyl-3,6-dinitro-1,3,6-triazacycloheptane. Ammonium nitrate has been shown to promote demethylolation in this series just as it does in the triazacyclohexane compounds. Analogies have therefore been drawn between these nitrolyses and that of hexamethylene-tetramine. Further comparisons derive from the isolation of 1-acetoxymethyl-3,6-dinitro-1,3,6-triazacycloheptane and 1-aceto-3,6-dinitro-1,3,6-triazacycloheptane by acetolysis of methylene-bis-dinitrotriazacycloheptane with acetic anhydride.
SOLUBILITY OF URANYL NITRATE HEXAHYDRATE AND THORIUM NITRATE TETRAHYDRATE IN ORGANIC SOLVENTS AT 20 °C.
Authors: Yaffe L.
Published: April 2011

A study has been made of the solubility of uranyl nitrate hexahydrate and thorium nitrate tetrahydrate in various organic solvents at 20 °C. In all the solvents investigated no case was found where the thorium nitrate tetrahydrate was more soluble than the uranyl nitrate hexahydrate. Hydrocarbons do not dissolve either compound to an appreciable extent. Addition of a ketone, aldehyde, or alcohol group enhances the solubility considerably. The simpler the compound the greater the solubility of the nitrate in any given family.
FURTHER DEVELOPMENTS IN THE VISTEX METHOD FOR THE DETERMINATION OF THE INTRINSIC VISCOSITY OF HIGH POLYMERS
Authors: Henderson D. A. , Legge N. R.
Published: April 2011

The intrinsic "vistex" viscosities of several series of butadiene–styrene copolymers of varying conversion and average molecular weight, dissolved directly from the latex in the vistex solvent mixture (toluene–isopropanol, 80/20 by volume), have been investigated and compared with the intrinsic viscosities of the corresponding coagulated, dried polymers dissolved in toluene. The intrinsic viscosity in toluene, [η]T, is related to the intrinsic vistex viscosity, [η]V, in toluene–isopropanol by the equation:—[Formula: see text]Hence, viscosity average molecular weight may be calculated from vistex measurements.A further development of the method has shown that, once the latex is dissolved in the vistex solvent, the solution may be diluted, within certain denned limits, by the addition of pure solvent (toluene) to obtain the several levels of concentration of polymer required for the determination of intrinsic viscosity. It is then possible, by extrapolation to zero concentration of polymer, to obtain a value for the intrinsic viscosity that is equal to the conventional intrinsic viscosity of the polymer in pure solvent after coagulation and drying under very mild conditions. The viscosity characteristics of butadiene–styrene copolymers of varying conversion appear to be represented, at conversions below the gel point, by the equation,[Formula: see text]where β′ and n are constants of the order of 0.25 and 1 for solutions in toluene and 0.1 and 2.5 respectively for vistex solutions. Distinct changes in β and/or n have been found at conversions in the region of and beyond the gel point.
LIGHT-SCATTERING APPARATUS AND TECHNIQUES FOR MEASURING MOLECULAR WEIGHTS OF HIGH POLYMERS
Authors: Hadow H. J. , Sheffer H. , Hyde J. C.
Published: April 2011

Apparatus is described for the measurement of small amounts of scattered light, dissymmetry of radiation, depolarization, and very small refractive index differences. Methods of calibration are critically examined. Benzene was adopted as a turbidity standard. Measurements were made on fractionated polystyrene of known molecular weight and on bovine serum albumin solutions. Values of the reduced intensity for benzene were obtained:[Formula: see text]Degree and sources of error are discussed
DETERMINATION OF LIGNIN IN CEREAL STRAWS
Authors: Adams G. A. , Castagne A. E.
Published: April 2011

Determination of lignin in wheat, oat, barley, and rye straw with 64%, 68%, 72%, 76%, and 80% (wt.) sulphuric acid showed that a minimum yield of lignin containing a maximum amount of methoxyl was obtained with the 72% sulphuric acid. In this respect, cereal straws differ from deciduous woods for which 72% sulphuric acid lignin determinations are unsuitable. Comparison of lignin determinations made with 72% sulphuric acid and with 42% fuming hydrochloric acid, on the same straws, after pretreatment with 1.0% hydrochloric acid, showed that the former method preserves a larger proportion of the methoxyl groups. Both methods recovered more total lignin methoxyl from untreated than from treated straws, with the sulphuric acid retaining the larger amount. It is concluded that lignin determination with 72% sulphuric acid on straws untreated with dilute acid yields a residue most representative of the 'true' lignin content, based on the criterion of maximum methoxyl recovery.
THE METABOLISM OF SCOPOLETIN BY HEALTHY AND VIRUS INFECTED POTATO TUBERS
Authors: Andreae Shirley R. , Andreae W. A.
Published: April 2011

After extraction of the chlorophyll, rolled leaves of potato plants infected with the leaf roll virus fluoresced a brilliant blue color in ultraviolet light. This blue fluorescence was not observed in leaves of healthy potato plants or plants infected with mild mosaic, rugose mosaic, or spindle tuber viruses. Neither was it found in unrolled leaves of leaf roll diseased plants. The blue fluorescent substance in rolled leaves had the same fluorescent and solubility properties as scopoletin.Scopoletin was metabolized by healthy and diseased potato tubers with the production of an unstable blue intermediary that turned bright yellow on standing. This reaction was accelerated by hydrogen peroxide and inhibited by heating the tissue to 65 °C., by cyanide, azide, hydroxylamine, and hydrogen sulphide. Healthy tubers were found to metabolize scopoletin more rapidly than leaf roll infected tubers.
FUNDAMENTAL STUDIES ON A SALTANT OF HELMINTHOSPORIUM SATIVUM
Authors: James Norman , Campbell N. E. R. , Gunner Chaim
Published: April 2011

A saltant of H. sativum disappeared from six different soils in which it was cultured in the laboratory within four weeks, whereas the indigenous flora persisted for nine weeks. During this nine week period numbers of bacteria showed no obvious trend, but numbers of fungi decreased. When cultured in sterilized portions of the above soils, the saltant showed a downward trend in numbers in the nine week period, a trend that was more obvious in some cultures than in others. Twenty-two of 221 isolates of fungi from soil, grain, and air, 45 of 286 isolates of Streptomyces, and 33 of 193 isolates of other bacteria produced evidence of antagonism to the saltant in spot inoculation studies. Filtrates prepared from two of the fungal isolates suppressed the growth of the saltant, as did also autoclaved portions of the nitrates. On the contrary, filtrates from three cultures of bacteria failed to suppress growth of the saltant, even though cultures of the bacteria did. The same 22 fungal isolates and 25 of the Streptomyces, when introduced separately into sterile soil along with the saltant, reduced the disease rating of barley seedlings below that produced by the saltant alone. The direct-count method of estimating numbers of spores of the saltant in a suspension was found to be reliable. Estimates based on the direct count were significantly greater than those made by the plate method. Estimates based on numbers of the saltant developing on potato dextrose agar containing small amounts of sterile soil were smaller than those made on the same medium without the soil. Even though the soil in the medium changed the pH of the medium, the difference in pH was considered not to be the primary factor in producing the lower estimates. Soil, either natural or heat sterilized, would contain the thermostable filterable substance or substances found to be produced by two species of fungi and probably produced by other species, likewise normally present in soil.
THE BIOLOGY OF LAEMOPHLOEUS FERRUGINEUS (STEPH.)
Authors: Rilett R. Omar
Published: April 2011

Life history and morphological studies were made on Laemophloeus ferrugineus (Steph.), a coleopterous pest of stored grain and other products.Temperature greatly affected the rate of development of L. ferrugineus. At a relative humidity of 75%, eggs at 80° F. hatched in four to five days, at 90° F. in three to four days, and at 100° F. in two to three days. Similarly, the period from hatching of the egg to the emergence of the imago at 70° F. was from 69 to 103 days, at 80° F. from 26 to 38 days, at 90°F. from 19 to 33 days, and at 100° F. from 17 to 26 days. First instar larvae did not survive at a temperature of 110° F.An increase in relative humidity within the range from 50 to 75% accelerated development during the larval feeding period. Above 75% relative humidity there was no significant acceleration of development. Mortality was very high at relative humidities below 50%—all larvae failing to develop at a relative humidity of 25%. At 90° F. the period from the hatching of the egg to the emergence of the imago at 50% relative humidity was from 28 to 42 days, at 65% relative humidity from 23 to 33 days, at 75% from 19 to 25 days, at 90% relative humidity from 18 to 25 days, and at 100% relative humidity from 18 to 27 days. The optimum environmental condition for the development of L. ferrugineus was from 90° F. to 100° F. at a relative humidity of 75% or higher.L. ferrugineus populations increased more rapidly in whole rye and wheat grain than in the same materials when they were coarsely ground. Just the opposite was true in the case of oats, barley, corn, sunflower, flax, and soybeans. Whole kernels of rye, wheat, corn, and rice were decreasingly susceptible to injury in the order named, while whole kernels of oats and barley, and the seeds of sunflower, flax, and soybeans were practically free from injury by L. ferrugineus at humidity levels normally occurring in stored grains and seeds. Although first instar larvae did gain access to the wheat germ of grain described commercially as being "whole, sound, and undamaged", they were unable to successfully attack whole wheat kernels that had no breaks in their bran layers. The breaks need only to be microscopic in size to allow penetration by the larvae.
SOME EFFECTS OF P32 ON THE DEVELOPMENT OF DROSOPHILA
Authors: Arnason T. J. , Irwin R. L. , Spinks J. W. T.
Published: April 2011

When freshly laid Drosophila eggs were placed in a graded series of P32 concentrations in the culture media, death of treated individuals occurred most frequently at the end of the larval period and in the pupal stages. No adults emerged from cultures having an initial concentration of 0.65 rutherford (rd.) or higher per ml. food. The calculated concentration of P32 expected to reduce emergence of adults to 50% is 0.120 rd. per ml. A dosage of 1.30 rd. per ml. prevents transformation of larvae to pupae. Three out of 132 X-chromosomes from males reared in medium having an initial concentration of 0.0325 rd. per ml. carried new recessive lethal "genes".
EXCHANGE OF MATERIALS IN A LAKE AS STUDIED BY THE ADDITION OF RADIOACTIVE PHOSPHORUS
Authors: Coffin C. C. , Hayes F. R. , Jodrey L. H. , Whiteway S. G.
Published: April 2011

On July 1, 1948, 100 millicuries of radioactive phosphorus, P32, was added to the surface of an acid bog lake of area 0.3 hectares (0.8 ac.) and depth 6 m., situated near Halifax, Nova Scotia. The lake had a well developed⁁ zone of cold, stagnant water at the bottom with a thermocline above. Within a few hours the P32 was taken up strongly by the sphagnum (which made up most of the lake margin), by the floating plankton, and by sponges. Within a few days it had reached the bodies of fishes (Fundulus and Notemigonus), and within a fortnight had accumulated in their skeletons and viscera. No appreciable uptake of P32 by such bottom rooted forms as the cranberry (Vaccinium) and leather leaf (Chamaedaphne) was observed for more than two weeks. Penetration of added phosphorus into the lake depths was very slow, and even at the end of eight weeks the material was only doubtfully detected at the bottom. There was no evidence of active uptake by bottom mud. The ratios of maximum count per wet weight of organism to maximum count for the same quantity of lake water were as follows:Zooplankton 40,000Fundulus 13,000Sponge 4500Sphagnum 400Vaccinium 300Blue-green alga 300Chamaedaphne 100Nuphar 80
THE DETERMINATION OF ERGOTHIONEINE IN SIMPLE SOLUTION AND IN BLOOD
Authors: Hunter G.
Published: April 2011

The diazo method of Hunter for the determination of ergothioneine in simple solution has been adapted to the Evelyn photoelectric colorimeter. The application of the method to the determination of ergothioneine in blood is described. Suitable blood filtrates are prepared by deproteinization with standard acetic acid oxalate solutions followed by removal of reduced glutathione with Goulard's lead acetate solution, and removal of excess lead with phosphate. By the method precise recovery is obtained of ergothioneine added to human blood.
THE DETECTION AND ASSAY OF HYALURONIDASE BY MEANS OF MUCOID STREPTOCOCCI
Authors: Murray R. G. E. , Pearce R. H.
Published: April 2011

A method is presented by which hyaluronidase may be detected by observing its action on the colony characteristics of mucoid strains of Streptococcus pyogenes and certain strains of Streptococcus of Lancefield Group C growing on agar. This effect is due to destruction of the capsules of these organisms and is caused by hyaluronidase from all sources tried. Bacteria are tested for hyaluronidase production by streaking on seeded plates; fluids are tested by using assay cylinders or filter paper disks.The method is convenient and has the advantage of detecting small concentrations of the enzyme, to a limit of between 0.001 and 0.0001 turbidity reduction units per ml. The test may be elaborated to give a means of biological assay that may be used where there are substances in the medium or diluting fluid that interfere with assays by other methods.Provided the colonies do not autolyze during the 12 to 18 hr. required for the test, all mucoid S. pyogenes strains are suitable. However, among the Group C strains one was found with a capsule not destroyed by hyaluronidase, indicating a separate capsular type.In testing certain genera for hyaluronidase production, notably Streptococcus and Micrococcus, antibiotic activity may interfere with the test. These inhibitory strains are relatively infrequent.
THE EFFECT OF IODOACETATE ON THE APPARENT SYNTHESIS OF DIPHOSPHOTHIAMINE DURING THE ESTIMATION OF THE COCARBOXYLASE ACTIVITY OF BLOOD EXTRACT
Authors: Blanchaer M. C. , Cohen L. H.
Published: April 2011

The usual method of determining diphosphothiamine (DPT) by its cocarboxylase activity proved unreliable when applied to blood extract because of a marked upward drift of the results during the period of measurement. This phenomenon, which was associated with excessively high recovery values, was tentatively attributed to a synthesis of DPT since the presence of 1 × 10−3 molar iodoacetate abolished the increase in carboxylase activity. Judging from recovery experiments, the addition of iodoacetate to the reactants permitted a more reliable estimation of the DPT content of blood extract.
L'ACTION ANÉMIANTE DE DEUX ANTAGONISTES DE LA LYSINE: L'HEXAHOMOSÉRINE ET L'ACIDE α-AMINOADIPIQUE
Authors: Pagé Edouard , Gingras Rosaire , Gaudry Roger
Published: April 2011

The addition of hexahomoserine (α-amino-ε-hydroxycaproic acid) to complete rations produces growth inhibition, anemia, and a considerable rise in blood plasma amino nitrogen in the rat. Simultaneous administration of lysine prevents the anemia and partially restores growth but does not affect the amino nitrogen level in the plasma. These effects of hexahomoserine and the antagonistic action of lysine are even more striking in animals previously depleted of lysine. Aminoadipic acid cannot replace lysine in the ration and it produces anemia in lysine-depleted rats. Its action is also counteracted by lysine. Liver concentrates and folic acid are ineffective in the prevention of the anemia caused by hexahomoserine.
ESTIMATION OF LIPASE IN DAIRY PRODUCTS: III. LIPASE ACTIVITY IN CULTURES OF MICRO-ORGANISMS AND IN CHEESE
Authors: Lubert D. J. , Smith L. M. , Thornton H. R.
Published: April 2011

The lipolytic activity in skim milk cultures of micro-organisms representing a number of species and genera were studied by the extraction–titration method described in the preceding paper. No evidence was found of a bacterial lipase having an activity optimum on the acid side of neutrality. No lipase active at approximately pH 5.0 was demonstrated in 20 samples of commercial cheddar cheese of varying age or one sample of blue veined cheese on measurement by the extraction–titration method or by the Peterson et al. method. Weak lipolytic activity was found in one sample of blue veined cheese by the extraction–titration method. No lipolytic activity at pH 8.5 was demonstrated by the extraction–titration method in the one sample of cheese tested at this pH.
ON THE ABSENCE OF PHOTONS AMONG THE DECAY PRODUCTS OF THE 2.2 MICROSECOND MESON
Authors: Hincks E. P. , Pontecorvo B.
Published: April 2011

An experiment is described which tests the hypothesis that the cosmic ray meson with a mean life of 2.2 μsec. decays into an electron and a photon. Geiger counter trays are used to select mesons incident on a graphite block, and to detect decay products emerging from the graphite. The electronic circuits record delayed coincidences that correspond to a decay event occurring between 0.6 and 5.3 μsec. after a meson is stopped. The absence of delayed coincidences of a type that could be attributed to the simultaneous emission of an electron and a photon, each of ~ 50 Mev., shows that the above hypothesis of the meson decay process is incorrect. The experiment also demonstrates the absence of a hypothetical unstable neutral meson among the decay products.
ISOTOPE SHIFT IN THE RESONANCE LINES OF ZINC
Authors: Crawford M. F. , Schawlow A. L. , Gray W. M. , Kelly F. M.
Published: April 2011

The isotopic structures of the Zn I resonance lines 2139 Å (4s21S0 − 4s4p1P1) and 3076 Å (4s21S0 − 4s4p3P1) excited in an atomic beam source have been resolved with a Fabry–Perot etalon. Shifts in cm.−1 relative to the Zn64 component are + 0.016 and + 0.033 in 2139 Å, and + 0.023 and + 0.046 in 3076 Å for Zn66 and Zn68, respectively. When the normal mass shifts are subtracted, the residual shifts for Zn68 are + 0.010 (2139 Å) and + 0.030 cm.−1 (3076 Å). The field effect theory of isotope shift predicts equal shifts and the specific mass effect predicts unequal shifts for the 1P and 3P levels. Therefore the difference of these residuals is a specific mass effect. The difference has the sense predicted by the specific mass theory and its value, 0.020 cm.−1, is a large fraction of the observed shifts. Thus the specific mass effect must be taken into account before the field effect theory can be used to obtain nuclear properties from isotope shifts in intermediate elements.
ENERGY DISTRIBUTION OF FISSION FRAGMENTS FROM U235 AND U233
Authors: Brunton D. C. , Hanna G. C.
Published: April 2011

New measurements have been made of the energy distribution of fission fragments. A coincident pulse technique has been used which measures simultaneously the energies of both fragments of a fission pair. Previous work in this field was limited in statistical accuracy owing to low fission rates. With the Chalk River high flux pile and a 30-channel pulse analyzer a rapid accumulation of data is made possible. The improved statistical accuracy has led to new results on the detailed association of fragment pairs and on the energy variation occurring in each fission mode. A careful comparison of U233 and U235 has been made.
THE DURATION OF THE 16 VOLT LEVELS OF NEON
Authors: Grant Frank A.
Published: April 2011

Electronic apparatus has been developed to determine the rate of decay of the 16 volt levels of neon after the interruption of an electrical discharge, by measurement of the absorption of a monochromatic light beam. The half life of the 3P2 metastable level has been determined as a function of pressure and discharge tube diameter. The 3P0 and 3P1 levels exhibit a pronounced departure from an exponential decay. The hypothesis of the imprisonment of resonance radiation is consistent with the measured duration of the 1P1 and 3P1 levels.
TWO NEW 2Σ–2Σ SYSTEMS DUE TO THE MOLECULE NO
Authors: Feast M. W.
Published: April 2011

The emission band system at 6000 Å found in discharges in flowing NO2 and attributed to NO+ by Jausserant, Grillet, and Duffieux has been examined at high dispersion and shown to be due to the transition of E2Σ+ (a new level) → A2Σ+ (the upper state of the γ system) of the NO molecule. The rotational and vibrational analysis of the system is given. The band system corresponding to the transition D2Σ+ (upper state of the ε system of NO) → A2Σ+ at 11,000 Å has also been observed and its analysis is presented. The separate nature of the D2Σ+ state from the A2Σ+ state is thus supported. Some brief remarks on other band structures found in discharges in flowing NO2 are included.
AN ATOMIC BEAM SOURCE AND SPECTROGRAPH FOR HYPERFINE STRUCTURE. NUCLEAR MOMENTS OF SILVER
Authors: Crawford M. F. , Schawlow A. L. , Kelly F. M. , Gray W. M.
Published: April 2011

An atomic beam source and a fast spectrograph which have been used effectively in hyperfine structure investigations are described. The camera objective of the spectrograph is an off-axis paraboloidal mirror. The procedures used to determine the nuclear moments of the two silver isotopes, I = 1/2 for each isotope, μ(Ag107) = − 0.087 n.m. and μ(Ag109) = − 0.160 n.m., are reported.
Deuterium Exchange in Trichlorethylene
Authors: Leitch L. C. , Bernstein H. J.
Published: April 2011

not available
OSMOTIC PRESSURE, MOLECULAR WEIGHT, AND VISCOSITY OF SODIUM ALGINATE
Authors: Donnan F. G. , Rose R. C.
Published: April 2011

This work shows how the molecular weight of sodium alginate can be determined by measuring the values of the osmotic pressure, P, in the presence of low concentrations of sodium chloride, and extrapolation of P/C to C = 0, where C is the concentration of sodium alginate. For different samples of sodium alginate the slope of the curve P/C against C was independent of the molecular weight. Molecular weight values from 48,000 to 186,000 were obtained. The intrinsic viscosity of the different samples were linearly related to the degree of polymerization.
SYNTHESIS IN THE SERIES OF ERYTHRINA ALKALOIDS
Authors: Wiesner K. , Clarke Frank H. , Kairys S.
Published: April 2011

One of the four racemates of XIV has been synthesized. The starting material was 2-cyclohexanone acetic acid. This compound was converted into the ethyl ester of 2-aminocyclohexylacetic acid which gave, with homoveratrylbromide, N-homoveratrylhexahydroöxindol. This compound by cyclization and hydrogenation was converted into XIV.
CONTRIBUTION TO THE SYNTHESIS OF ORGANIC DEUTERIUM COMPOUNDS: I. DEUTEROPOLYMETHYLENE
Authors: Leitch Leonard C. , Gagnon Paul E. , Cambron Adrien
Published: April 2011

An improved method of preparing polymethylene, (CH2)n, by the decomposition of diazomethane is described. A new polymer, polyethylidene, (CH3∙CH)n, has been obtained from diazoethane by the same reaction. Diazomethane-d2 is reported for the first time. A new deuterated polymer, (CD2)n, obtained by the decomposition of diazomethane-d2 has been synthesized.
THE DENSITY OF WATER SORBED ON CHARCOAL
Authors: McDermot H. L. , Tuck N. G. M.
Published: April 2011

The apparent volume of water sorbed by a zinc chloride activated charcoal has been measured over the entire range of relative pressures, employing an apparatus especially designed to eliminate carry-over of water vapor into the sorption cell. The apparent volume has been found to be consistently greater over the entire sorption isotherm than the normal volume of an equal weight of liquid water, and it tends to be slightly higher on desorption than on adsorption. The results are in qualitative agreement with those of Wiig and Juhola and in marked disagreement with those of Morrison and McIntosh.
AN APPARATUS FOR THE LOW TEMPERATURE FRACTIONATION OF SMALL GAS SAMPLES
Authors: Roy D. J. Le
Published: April 2011

A simple apparatus has been developed for fractionating polycomponent gas samples at temperatures at which the take-off pressure is of the order of 0.5 mm. Fractions as small as 0.06 cc. of gas have been isolated and their vapor pressures determined.
THE APPLICATION OF THE ARNDT–EISTERT REACTION TO THE SYNTHESIS OF FATTY ACIDS OF HIGH MOLECULAR WEIGHT
Authors: Vandenheuvel F. A. , Yates P.
Published: April 2011

The Arndt–Eistert reaction offers a convenient method for the synthesis of the higher members of the aliphatic carboxylic acid series. Nonadecanoic acid, eicosanoic acid, and heneicosanoic acid have been prepared successively from stearic acid in good yields. An efficient method of purification of the synthetic products is described. The ultraviolet absorption maxima for some diazoketones derived from the higher members of the aliphatic carboxylic acid series are recorded.
THERMODYNAMIC PROPERTIES OF ISOTOPIC COMPOUNDS OF SULPHUR
Authors: Tudge A. P. , Thode H. G.
Published: April 2011

Using the well known methods of statistical mechanics, partition function ratios for many isotopic sulphur compounds have been calculated. These partition function ratios are used to determine equilibrium constants for many possible exchange reactions involving the isotopes of sulphur. The results indicate that considerable fractionation of the sulphur isotopes can be expected in laboratory and natural occurring processes. The predicted exchange constants are discussed in the light of recent results on the distribution of the sulphur isotopes in nature.
AN 80 °C. ISOTHERMAL CALORIMETER
Authors: Coffin C. C. , Devins J. C. , Dingle J. R. , Greenblatt J. H. , Ingraham T. R. , Schrage S.
Published: April 2011

An 80° isothermal naphthalene calorimeter analogous to the Bunsen ice calorimeter has been constructed and calibrated. The heat to be measured is made to change the solid/liquid ratio of naphthalene at its melting point, and the resulting volume change is determined by the displacement of mercury in a horizontal capillary tube. The naphthalene chamber is surrounded by the vapor of benzene boiling under an automatically controlled pressure at the melting point of naphthalene. The benzene vapor and the partially frozen naphthalene are separated by an evacuated space.This 80° calorimeter is four times as sensitive as the ice calorimeter and is much more convenient to operate. It is readily adapted to micro work and can be used for fast or slow endothermic or exothermic processes. In the setup described, heats up to about 400 cal. may be measured with a reproducibility of the order of 0.1%. Two different methods of calibration, however, gave "constants" differing by almost 1%. It is thus evident that the instrument must be calibrated as nearly as possible in the way in which it is to be used.
DARK REACTIONS OF CHLOROPLAST SUSPENSIONS
Authors: Clendenning K. A. , Gorham P. R.
Published: April 2011

Chloroplast suspensions from the majority of plant species produce titratable acidity in darkness when mixed with ferricyanide – ferric oxalate solution. The rate of production and yield of acid increases between pH 6.0 and 7.5. This oxidation–reduction requires the presence of ferricyanide or ferric oxalate and does not involve enzymes. The nonsugar reducing substances in chloroplast suspensions which participate are water-soluble, and may include ascorbic acid, glutathione, and tannins. By applying a correction for dark acid production, photochemical activity in chloroplast suspensions showing this reaction may be measured by the Holt and French titration method. Boiled leaf sap of Broad Windsor bean produces carbon dioxide rapidly when mixed with ferricyanide – ferric oxalate solution, apparently by oxidative decarboxylation. Crude chloroplast suspensions from this species also exhibit oxygen absorption and dark acid production. Simultaneous measurement of these reactions shows no evidence of quantitative relations. The precipitation of oxalate causes an alkaline drift in pH when crude chloroplast suspensions of Lycopodium or Sedum are mixed with Hill solution in darkness. With crude spinach chloroplast suspensions, interference by dark reactions in photochemical activity measurements is generally negligible.
PHOTOCHEMICAL ACTIVITY OF ISOLATED CHLOROPLASTS IN RELATION TO THEIR SOURCE AND PREVIOUS HISTORY
Authors: Clendenning K. A. , Gorham P. R.
Published: April 2011

A survey of the major subdivisions of the plant kingdom revealed photochemical activity in chloroplasts and chloroplast fragments isolated from unicellular and filamentous green algae, liverworts, horsetails, herbaceous monocotyledons, and dicotyledons. Active chloroplasts were not obtained from mosses, ferns, gymnosperms, and woody angiosperms. Among 80 species and varieties tested in Hill solution by the titration method, 45 showed photochemical activity quotients above 100, 19 had quotients above 500, and six (millet, flax, spinach, lamb's-quarters, Swiss chard, and lettuce) showed quotients above 1000. Photochemical activity varied greatly within both genera and species. The majority of the chloroplast suspensions produced acid in darkness when mixed with ferricyanide – ferric oxalate solution. Natural inhibitors of photochemical activity were found in the cell sap and cytoplasm of several species.Chloroplast activity quotients in ferricyanide – ferric oxalate and quinone solutions increased with leaf maturation, and declined with senescence. Chloroplasts isolated from very young green leaves of active species were photochemically inactive. The activity of the chloroplasts was relatively insensitive to the supply of essential mineral nutrients and water as well as to growth temperature. Chloroplasts isolated from leaves showing pronounced symptoms of nitrogen, iron, copper, manganese, or magnesium deficiency had low activity quotients, but remained photochemically active until the leaves were about to die. The observed responses to previous illumination and darkness did not support the hypothesis that a labile photosynthetic intermediate, stored in the chloroplasts, is required for oxygen production after isolation.Chloroplast activity was stabilized for weeks by snap-freezing suspensions containing 0.5 M sucrose and storing at or below −40 °C. Lyophilization did not prevent storage deterioration at higher temperatures.
STUDIES IN SEPTORIA LYCOPERSICI SPEG.
Authors: MacNeill Blair H.
Published: April 2011

Investigations into the biology of Septoria lycopersici Speg., a leaf-spotting fungus parasite of the tomato, reveal that this fungus species is composed of at least two physiologic races which show both qualitative and quantitative differences in their pathogenicity. Other factors, such as humidity, temperature, light, and host nutrition, which influence host–parasite interaction, have been shown to cause further variability in the symptomatological picture. Studies of spore germination and the prepenetration phase of host–parasite relationships suggest an interaction before actual penetration which, in some cases, is sufficient to condition the germination of the spores themselves. A minimum period of 48 hr. at saturation is required to promote germination and stomatal penetration, but this experience at high humidity need not be continuous. The fungus inhabits an intercellular locus, but is very intimately associated with the cells of the tissues parasitized. There is no evidence of action in advance; rather a certain measure of host–parasite equilibrium is maintained, and the pathogen is enabled to complete its life cycle and reinitiate infection. Although this evidence suggests a rather high degree of specialization of parasitism, the nature of the host–parasite association is yet considerably removed from that of an obligate relationship. It is pointed out that while S. lycopersici might be considered, in the sense of de Bary, either as a facultative saprophyte or an obligate parasite, its peculiar behavior makes it exceedingly difficult, if not impossible, to place it into any one category which might describe its biological activity.
AN AGAR-SHEET METHOD OF TESTING THE EFFICIENCY OF SEED TREATING MACHINES
Authors: Machacek J. E.
Published: April 2011

The efficiency of a seed treating machine depends to a considerable extent on the uniformity with which the fungicide used for treatment is mixed with the seed. The uniformity of treatment may be ascertained by placing treated seeds, at 2-in. intervals, on large sheets of inoculated potato-sucrose agar. In the preparation of these sheets, melted, acidified agar is poured in a uniform layer over panes of glass and, when the agar has solidified, it is dusted heavily with spores of Penicillium purpurogenum Stoll. After the treated seed is placed on the agar, the culture is covered with a sheet of glass and incubated for two days at room temperature. The uniformity of treatment may then be determined from the variability in diameter of the zones of inhibition around the seeds. This technique may also be used for determining the comparative potency of different fungicides, and the rate at which they are lost from the seed.
QUALITATIVE AND QUANTITATIVE DETERMINATION OF THE WHEAT LEAF CARBOHYDRATES
Authors: Roberts D. W. A.
Published: April 2011

The nonreducing sugar in wheat leaves is probably entirely sucrose. It is the only abundant sugar. Free reducing sugars are absent, or almost absent from wheat leaves grown under the conditions described. The reducing power in the cleared alcoholic extracts of the leaves is, at least, partly due to degradation products of ascorbic acid. Other nonsugar reducing substances also are apparently present. The alcohol insoluble residue from wheat leaves contains little or no fructosan, dextrin, or starch at the two and one-half week old stage. Satisfactory methods for extracting and determining the sucrose are described. The following methods gave satisfactory results with wheat leaf extracts: the reducing power methods of Hanes and Somogyi after acid or preferably invertase hydrolysis, Ost's solution for fructose residues, the method of Neuberg and Strauss, the colorimetric resorcinol method. The latter method gives only approximate values for fructose residues unless the sugar concentration is high; the method is then fairly reliable. The following methods did not give satisfactory results: Hanes and Somogyi methods for free reducing sugars initially present in the extract, the hypoiodite titration for aldose sugars, and Sieben's method for fructose determination.
THE TICKS OF ALBERTA WITH SPECIAL REFERENCE TO DISTRIBUTION
Authors: Brown John H. , Kohls Glen M.
Published: April 2011

The material in this paper is the result of 11 years of collecting over the accessible portions of Alberta, with the exception of the settled area from Lac La Biche to Fort McMurray. The area north from Grimshaw to Fort Vermilion has not been surveyed in detail, and further collections will be made. Nine species are recorded: Dermacentor andersoni Stiles, D. albipictus (Packard), Haemaphysalis chordeilis (Packard), H. leporis-palustris (Packard), Ixodes angustus Neumann, I. kingi Bishopp, I. sculptus Neumann, I. spinipalpis Hadwen and Nuttall, and Otobius lagophilus Cooley and Kohls. Maps showing the known distribution of the several species in Alberta are presented.