bluuebunny/crossref_metadata_2025 huggingface dataset:
PRODUCTION AND PROPERTIES OF 2,3-BUTANEDIOL XXXVI. LINEAR POLYESTERS OF 2,3-BUTANEDIOL
Authors: Watson R. W. , Grace N. H. , Barnwell J. L.
Published: April 2011

New polyesters with basic units containing 6, 7, 8, 9, 10, 13, and 14 chain atoms have been prepared from levo-2,3-butanediol and ethyl oxalate, ethyl malonate, dimethyl terephthalate, maleic anhydride, succinic, glutaric, adipic, azelaic, and sebacic acids, and from meso-2,3-butanediol and o-phthalic anhydride. Esterification of 2,3-butanediol with a dibasic acid, or its anhydride, is accompanied by a side reaction, in which butanone-2 and the cyclic methyl ethyl ketal are formed. The purified polyesters, with the exception of the poly-malonate, appear to be composed of regularly recurring acid and diol segments over the molecular weight ranges investigated. Without exception they are amorphous resins or balsams. Polyesters formed from saturated aliphatic dibasic acids become progressively softer as the number of methylene groups in the acid segment increases. The polymeric oxalate, on distillation in vacuo, is converted to a macrocrystalline cyclic monomer.
THE OXIDATION OF CARBON MONOXIDE BY SOLID SILVER PERMANGANATE REAGENTS: II. KINETIC STUDIES WITH SILVER PERMANGANATE – ZINC OXIDE
Authors: Katz Morris , Grant G. A. , Riberdy R.
Published: April 2011

The kinetic equations of the adsorption wave were applied to the oxidation of carbon monoxide in an air stream by granular silver permanganate – zinc oxide reagent. The following relations have been investigated in this system: (a) the concentration of the escaping gas as a function of time, (b) the effect of initial concentration, column length, and flow rate on breakdown time, (c) the influence of granule size on breakdown time and rate of reaction. The critical column length was found to be dependent on flow rate and independent of initial concentration. Critical column lengths of approximately 0.4 cm. to 1 cm. were found for the range of flow rates studied. The relation found between granule size and breakdown time does not completely agree with the theoretical equations. As the mean diameters of the granules decreased from 2.2 mm. to 0.90 mm. the breakdown time increased, but a decrease in mean diameter from 0.90 to 0.30 mm. resulted in a reduction of breakdown time. Although the results are in general agreement with the equations developed by Hinshelwood and Klotz, certain deviations from the theoretical treatment were evident.
TUMOR INDUCTION IN VICIA FABA AND OTHER HOSTS BY AGROBACTERIUM RUBI (HILDEBRAND) STARR AND WEISS
Authors: Coleman L. C.
Published: April 2011

In a search for suitable material for a cytological study of plant tumors, pure and virulent cultures of Agrobacterium tumefaciens were inoculated into stems of young Vicia faba plants without result. On the other hand, a bacterium isolated from Himalaya blackberry produced large tumors. A comparison of the two forms as to their virulence on other plant species showed that the blackberry organism would not attack tomato, Nicctiana glutinosa, and Datura medeloides, all highly susceptible to A. tumefaciens. Sunflower proved to be a common host to the two pathogens, but the host responses showed significant differences. The tumors caused by the blackberry organism were smaller and were not accompanied by epinasty of the leaves immediately above the tumor, a characteristic feature associated with tumor formation induced by A. tumefaciens. From cultural characters and differences in host range, it was decided that the blackberry organism belongs to Agrobacterium rubi (Hildebrand) Starr & Weiss., a species considered as confined to Rubus species. Its host range is obviously much wider than this and, as it embraces plants only slightly or not at all susceptible to A. tumefaciens, it is likely to prove an important addition to this species in providing material for the study of plant tumors.
THE ELONGATION OF FUSIFORM CAMBIAL CELLS IN CHAMAECYPARIS
Authors: Bannan M. W. , Whalley Barbara E.
Published: April 2011

Studies of the secondary xylem and phloem indicated that after their origin in anticlinal division, sister fusiform initials usually elongated rapidly, particularly at their overlapping tips. After this first phase, rate and amount of extension varied, both along the overlap and at the opposite ends. Often elongation proceeded in a somewhat periodic fashion, being determined in part by inherent factors and in part by position and behavior of the adjoining cells. Sometimes elongating tips were temporarily stalled at blocking rays, while at other times very rapid extension occurred in association with loss of a neighboring initial from the cambium. Growth appeared to be apical, "intrusive" in the sense that the elongating tips thrust between other cells. No evidence was found to support the theory of simultaneous elongation of considerable portions of adjoining walls by "symplastic" growth.
NUCLEAR CONDITIONS IN NORMAL STEM TISSUE OF VICIA FABA
Authors: Coleman L. C.
Published: April 2011

Previous cytological studies of plant tumors have been carried out on unsuitable material, and on the assumption that the normal tissues in which tumors are induced are exclusively diploid. The present study investigates the condition in normal stem cortex and pith of Vicia faba, in which tumors can be regularly induced through inoculation with pure cultures of Agrobacterium rubi. Mitoses were induced by treatment with indole-3-acetic acid, and it was found that a very considerable degree of polyploidy exists in both tissues. In the pith the percentage of polyploid mitoses increases with some regularity from the nodal to the mid-internodal region, where it may be as high as 50% of the total. In the cortex, the difference in this regard is less striking, but still exists. Both tetraploid and octoploid cells were found, the latter being less than 10% of the total. In both cases, there was usually close association of homologues in both pro- and metaphase, but in the cortex a considerable number of nuclei did not show this association. The pairing is at times accompanied by chiasma formation. These findings must be taken into account in studying the relation of polyploidy to tumor development.
NATURAL ANCHORING OF THE RED ALGA, GRACILARIA CONFERVOIDES (L.) GREV. ON UNSTABLE BOTTOM BY ASSOCIATION WITH AN ANNELID WORM
Authors: Pillsbury R. W.
Published: April 2011

Clumps of Gracilaria confervoides (L.) Grev. several meters long and several kilograms in weight have been found growing on clean sand bottom. These plants do not arise from the usual discoid holdfast on a buried stone, etc., but each is anchored by enwrapment of main strands to the tube of a worm, Diopatra ornata Moore. This enwrapping was observed to occur by mechanical obstruction of loose hanks of the alga by projecting worm tubes during extreme low tides on winter nights. In three months the alga was cemented to the tube by unexplained action. A coaction of alga and tube worm apparently exists that establishes plant shelter for small animals on an otherwise unsuitable substratum, thus increasing the complexity of the community on such sites. It is suggested that perennating marine algae produce much the same seasonal shelter for animals as do the deciduous plants of terrestrial communities.
TWO NEW OUTBREAKS OF PHOMOPSIS LOKOYAE IN BRITISH COLUMBIA
Authors: Thomas G. P.
Published: April 2011

Young Douglas fir in British Columbia sustained damage from Phomopsis lokoyae Hahn during the winter of 1948–49. Damage in the form of annual stem and branch cankers, leader die-back, and stem girdling was confined to trees, or parts of trees, 4 in. in diameter or less. Fungus activity was confined to Douglas fir bark and cambium tissues for the single dormant season. Outbreaks of the fungus are recurrent in British Columbia, reaching epidemic proportions only at irregular intervals.
THE PROTEOLYTIC ENZYMES OF MICROORGANISMS: I. SURVEY OF FUNGI AND ACTINOMYCETES FOR PROTEASE PRODUCTION IN SUBMERGED CULTURE
Authors: Dion W. M.
Published: April 2011

Of 289 fungi and actinomycetes tested, only 20 were found to produce high yields of proteolytic enzymes when grown in submerged culture. Strains of Gliocladium roseum and Alternaria tenuis were found to be consistently proteolytic, and other good strains were also found in the genera Chaetomium, Sordaria, Epicoccum, Rhizoctonia, and Streptomyces.
THE BLACK ROOTROT DISEASE OF TOBACCO.: II. PHYSIOLOGIC SPECIALIZATION OF THIELAVIOPSIS BASICOLA ON NICOTIANA TABACUM
Authors: Stover R. H.
Published: April 2011

Thielaviopsis basicola (Berk. & Br.) Ferraris exists in nature in two distinct forms, termed the brown and the gray wild type, which are differentiated on potato dextrose agar. Pathogenicity on tobacco was found to be a function of the wild type culture used. All gray wild type cultures were less pathogenic than the brown. The brown wild type cultures consisted of at least two physiologic races. Race I is found in the "old belt" of Ontario, and in Quebec, Ohio, and Connecticut. Race II is present in the "new belt" of Ontario and in Kentucky. Race II and all gray wild type cultures are less pathogenic than Race I. All cultural mutants were less pathogenic than wild type cultures.
NITROGEN DETERMINATION IN WHEAT LEAVES
Authors: Roberts D. W. A.
Published: April 2011

A survey of the more promising modifications of the Kjeldahl method for nitrogen determination indicates that the method using mercuric oxide as the catalyst as recommended by the Association of Official Agricultural Chemists is the most satisfactory. However small discrepancies were found when this method was applied to wheat leaves fractionated into soluble and protein (actually coagulable and indiffusible) nitrogen fractions. This method includes all the nitrate nitrogen in wheat leaves together with the organic nitrogen even when no pretreatment with salicylic acid is used. A simple and satisfactory method of separating coagulable and indiffusible nitrogen from soluble nitrogen in wheat leaves and seedlings is described.
INTERRELATIONS OF DAILY METABOLIC CYCLE, ACTIVITY, AND ENVIRONMENTAL TEMPERATURE OF MICE
Authors: Hart J. S.
Published: April 2011

The daily metabolic cycle of fully fed, adult white mice, at temperatures from − 8 °C. to 37 °C., averaged 48 ml. of oxygen per mouse per hour between the highest nocturnal and lowest diurnal values, but this value was significantly greater at the higher temperatures. Over the same temperature range, forced activity of mice in a rotating metabolism chamber, up to approximately one-half the maximum running speeds studied, resulted in direct superimposition of work metabolism upon that of rest, with a constant metabolic increment at all temperatures. At the maximum running speeds the metabolism produced by the work decreased with decreasing temperature, with some gain in efficiency. The daily metabolic cycle fell within the activity range in which a given degree of work produced the same increment in oxygen consumption at all temperatures. These studies lead to the hypothesis that, in mice, some of the metabolic components of the daily cycle are additive over the biokinetic range. This results in a very large energy expenditure at low temperatures.
THE STABILITY OF ASCORBIC ACID IN SOLUTION
Authors: Campbell James , Tubb W. G.
Published: April 2011

The stability of ascorbic acid in aqueous solution was increased under certain conditions by oxalic acid, metaphosphoric acid, glutathione, thiourea, and sodium diethyldithiocarbamate. A slight protective effect was exerted by creatinine; but formic, phthalic, and orthophosphoric acids, creatine, and caffeine had no demonstrable effect. In all these instances the pH, concentrations of reagents, etc., must be considered. In oxalate and thiourea maximum stability occurred at pH 2.5 to 3.0 and in glutathione at pH 3.6 to 4.2. The latter substance itself was also most stable at pH 3 to 4. At the optimum pH a concentration of 40 mM of oxalate gave maximal protection, this being independent of the initial concentration of ascorbic acid over the range 2 to 20 mM. Thus a stoichiometric relationship between the concentrations of the ascorbic acid and the oxalate required for protection was not found. A region of minimum solubility of oxalate in water occurred at pH 2.4 to 3.0, which coincides with the pH at which the maximum protective effect occurs and with the highest relative concentration of sodium hydrogen oxalate (or sodium hydrogen oxalate monohydrate). The absorption of ultraviolet light by ascorbic acid was altered by pH, the maximum shifting from 244 to 268 mμ from pH 2.8 to 4.5. The molecular extinction coefficient of ascorbic acid also changed with pH and was minimal at pH 4.0. This effect occurred in oxalate, which has a specific protective effect, and also in formate and orthophosphate, which have no specific protective effect. The possible mechanisms for the protection of ascorbic acid by oxalate are discussed.
A COMPARISON OF THREE METHODS FOR THE ASSAY OF COMMERCIAL INSULIN PREPARATIONS
Authors: Young D. M. , Reid D. B. W. , Romans R. G.
Published: April 2011

Each of 14 commercial insulin preparations was assayed for insulin activity using three biological assay methods. In Assay I, 32 rabbits were employed using the "twin cross-over" design. Per cent reductions of blood sugar calculated from blood-sugar levels determined before and one and one-half, three, and five hours after the subcutaneous injection of insulin were used in estimating potency. In Assay II, 16 rabbits were used in a 4 × 4 Latin square design. Blood-sugar levels determined 50 min. after the intravenous injection of insulin were used in estimating potency. In Assay III, 288 mice were employed in a two-level quantal response design. The proportions of animals convulsing in groups of 36 mice after the subcutaneous injection of insulin were used in measuring potency. The agreement between results obtained by the three methods was found to be satisfactory. The average standard error for the estimate of potency was 13% for Assay I; 10% for Assay II; and 9% for Assay III.
TOXIN PRODUCTION IN AERATED CULTURES OF CORYNEBACTERIUM DIPHTHERIAE
Authors: Howatt F. F. , Reed G. B.
Published: April 2011

In this paper a comparison is made between the growth and toxin production of Corynebacterium diphtheriae in aerated and classical still cultures. It is shown that in well aerated cultures fermentation proceeds more rapidly and toxin appears earlier than in still cultures. However, to obtain maximum results in aerated cultures it is necessary to increase the amount of fermentable substance over that present in the media of still cultures. When cultures are aerated with two to three volumes of air per minute and an extra amount of fermentable carbohydrates is added to the growing cultures at a suitable interval a higher yield of toxin is obtained than in still cultures in similar media. The maximum concentration of toxin, moreover, is reached in the aerated cultures after about 60 hr. of incubation as compared with about 120 hr. in still cultures.
USE OF OLEIC ACID – ALBUMIN AGAR MEDIUM FOR THE STUDY OF STREPTOMYCIN RESISTANCE OF MYCOBACTERIUM TUBERCULOSIS
Authors: Siebenmann Charles O.
Published: April 2011

The oleic acid – albumin agar, proposed by Dubos and Middlebrook as a diagnostic medium for the isolation of Mycobacterium tuberculosis, proved useful for determining streptomycin resistance. By growing cultures of M. tuberculosis on this translucent substrate, containing graded amounts of streptomycin, a close correlation was found between the observed streptomycin resistance and that determined in fluid tween-albumin medium. The initial presence of a few organisms, showing a slight resistance to streptomycin, was found not to be an exclusive characteristic of cultures developing drug resistance in the course of streptomycin therapy. Cultures not developing resistance may also contain such resistant cells.
THE EFFECTS OF SOME URINARY EXTRACTS ON GASTRIC SECRETION IN THE SHAY OPERATED RAT
Authors: Skelton Floyd R. , Grant Gordon A.
Published: April 2011

Following the general procedure of Risley, Raymond, and Barnes the effects of urinary extracts on gastric secretion have been studied in the Shay operated young, male, albino rat. The procedure consisted of ligating the pylorus following a 24 hr. fast. Immediately postoperatively the test material was administered. After a five hour period the stomach was removed, opened, and rinsed into 10 ml. of distilled water. An aliquot of this was titrated for its free and total acid content. Human chorionic gonadotrophin and preparations obtained by the benzoic acid absorption method from human and equine pregnancy urine were studied for their effects on gastric section using the above technique after subcutaneous, intraduodenal, and oral administration. It was found that chorionic gonadotrophin caused gastric secretory depression at a dose level as low as 10 mgm. per rat subcutaneously. Both the human and equine preparations were observed to reduce the gastric secretion proportionately to the dose when administered subcutaneously. When administered by intraduodenal injection at the time of operation, the equine preparation was active but required several times the subcutaneous dose to produce comparable results. Oral administration of both equine and human pregnancy urine extracts showed antisecretory activity only in the former at the dose levels employed. In addition, the effects of possible complicating factors such as estrogens, pyrogens, and nonspecific damage on gastric secretion have been investigated and found to play no appreciable part in the results produced by the urine fractions.
THE EFFECT OF ADRENOCORTICOTROPHIC HORMONE AND SURGICAL OPERATIONS ON IODINE EXCRETION
Authors: Gemmell J. P. , Perry W. F.
Published: April 2011

Further investigations have been carried out on the previously reported increase in iodine excretion which occurs following the stress of surgical operations. By means of adrenocorticotrophic hormone it was demonstrated in four subjects that increased activity of the adrenal cortex does not of itself cause an increase in iodine excretion. In six patients subjected to elective surgical procedures it was shown with the aid of radioactive iodine that the inorganic iodide of the body tissues is not the source of increased iodine excretion which follows such operations. Other possible causes and sources of the postoperative increase in iodine excretion are discussed.
ANTIBIOTICS PRODUCED BY MICROCOCCI AND STREPTOCOCCI THAT SHOW SELECTIVE INHIBITION WITHIN THE GENUS STREPTOCOCCUS
Authors: Loeb L. J. , Murray R. G. E.
Published: April 2011

Two strains of Micrococcus epidermidis and five of Micrococcus pyogenes were found to produce antibiotics that were detected by using a mucoid Streptococcus pyogenes as test organism. The antibiotics were also active against some other Gram-positive organisms, but not against Gram-negative bacteria. The M. epidermidis strains inhibited most β-haemolytic streptococci with the exception of mucoid Lancefield Group C. The M. pyogenes strains were active against the majority of mucoid S. pyogenes (Group A), but few or none of the nonmucoid strains were inhibited. Streptococci of Groups B, C, and G were not affected. On the basis of antibacterial spectrum and characteristics of the antibiotics (dialysis, stability, and production curves) the seven strains were divided into four groups producing antibiotics of different types.Three strains of β-haemolytic streptococci were tested which were known to produce antibiotics. Two of these showed a selective inhibition similar to the micrococci. They inhibited all of the mucoid S. pyogenes but few of the nonmucoid; they inhibited all strains of Group C, both mucoid and nonmucoid, but did not inhibit the Group G strains tested.These observations suggest that, apart from capsulation, there may be a fundamental metabolic difference between the majority of mucoid and nonmucoid strains of S. pyogenes.
FURTHER WORK ON THE NUTRITION OF DUCKLINGS: A.—LIPOTROPIC FACTORS. B.—SULPHUR AMINO ACID REQUIREMENTS
Authors: Demers J. M. , Bernard R.
Published: April 2011

Using a purified diet deficient in choline and containing 18% casein, it has been found that in the duckling: (a) betaine and aminoethanol have little or no lipotropic activity, are poor growth factors, and cannot prevent perosis; (b) monomethylaminoethanol and dimethylaminoethanol, on the other hand, have well marked lipotropic activity. Both substances stimulate growth and are antiperotic, dimethylaminoethanol being the most active of the two in these respects; (c) ducklings, like chicks, appear unable to methylate aminoethanol to any extent; (d) a level of 28% casein is more satisfactory than one of 18% in the prevention of fatty infiltration of the liver in ducklings.Betaine and methionine have a definite lipotropic activity, when fed to ducklings along with a semipurified diet containing peanut meal as the only natural ingredient. The substitution of yellow corn meal to sucrose in the above semipurified diet inhibits the lipotropic activity of methionine, without affecting that of betaine.The availability of a protein low in sulphur amino acids has resulted in the preparation of a more hypolipotropic diet. On this diet, ducklings presented livers containing, on the average, 24% of lipids. Methionine added to this diet is strongly lipotropic, but is without effect on growth. Methionine will promote growth only in presence of choline.Ducklings like chicks and poults appear to be able to convert methionine to cystine. In presence of 0.4% cystine, approximately 0.5% methionine is required for normal growth.
THE USE OF PRISCOLINE (2-BENZYLIMIDAZOLINE HYDROCHLORIDE) AS A TEST IN OCCLUSIVE ARTERIAL DISEASE
Authors: Doupe J. , Cherniack R. M.
Published: April 2011

In 19 subjects with chronic occlusive arterial disease an intramuscular injection of 75 mgm. Priscoline (2-benzyl-2-imidazoline) was found in most cases to produce a greater rise in toe temperature than did the body warming procedure of Gibbon and Landis. In five subjects the vasodilating property of Priscoline was found to be superior to that of spinal anesthesia. In four cases the results with Priscoline predicted the effect of sympathectomy with greater accuracy than did the body warming test. The superiority of the Priscoline test was ascribed to the presence of denervation sensitivity due to a disturbance of sympathetic innervation occurring in association with occlusive arterial disease.
POLAROGRAPHIC DETERMINATION OF TITANIUM IN PAINT PIGMENTS
Authors: Potts B. R.
Published: April 2011

A simple, rapid polarographic procedure for the determination of titanium in paint pigments has been developed, using a sulphuric acid – tartaric acid medium. The accuracy and precision of the method are satisfactory for routine testing operations. The interference of other common pigment ingredients is discussed, and a procedure suggested for the removal of copper and antimony prior to analysis.
THE OXIDATION, IGNITION, AND DETONATION OF FUEL VAPORS AND GASES: XIII. THE 12:1 COMPRESSION RATIO PERFORMANCE OF THE C.F.R. SPARK IGNITION ENGINE USING TOWN GAS; COMPARISON WITH DIESEL ENGINES
Authors: King R. O. , Durand E. J. , Wood Bernard D. , Allan A. B.
Published: April 2011

The experiments described are part of a series being made to determine the factors which limit the power and efficiency of an Otto cycle spark ignition engine using Toronto town gas nearly free of sulphur. The air supply was unthrottled and power was varied by varying the gas supply. Mixture strength was "correct" at an air-to-gas ratio of 4:1. Trials were run with jacket coolant temperatures of 100°, 140°, 212°, and 295° F., the compression ratio being always 12:1 and the speed 900 r.p.m. A maximum indicated thermal efficiency of 43% was attained with coolant temperatures of 100° and 140° F. and an air-to-gas ratio of 8:1. Thermal efficiency diminished rapidly as air-to-gas ratio was increased and tended to become zero instead of the air standard value. The brake horsepower became zero for an air–gas ratio of approximately 11:1, the mixture strength being then 64% weak. Thus the engine was run at 900 r.p.m. from zero to full load, that is with 100% quality control. The maximum I.M.E.P. of 144 lb./sq. in. was obtained with a jacket coolant temperature of 100° F. The indicated thermal efficiency was then 36% and the mixture 10.7% rich. The performance of the Otto cycle engine could probably be improved by running at higher speeds but even at the relatively low speed of 900 r.p.m. for that type, it compared favorably in most respects with that of the compression ignition type of Diesel engine.
THE OXIDATION, IGNITION, AND DETONATION OF FUEL VAPORS AND GASES: XIV. THE CAUSE OF THE EFFECT OF HYDROGEN SULPHIDE TO REDUCE THE COMPRESSION RATIOS AT WHICH FUEL GASES CAN BE USED IN SPARK IGNITION ENGINES
Authors: King R. O. , Durand E. J. , Wood Bernard D. , Allan A. B.
Published: April 2011

Experimental results are given for trials of the C.F.R. engine at 900 r.p.m. and 12: 1 C.R. on Toronto town gas alone and with an addition of hydrogen sulphide. The sulphide led to such severe preignition that measurements of power were impossible except for very weak or very rich mixtures. The former included the 50% weak mixture for which thermal efficiency is a maximum. The sulphide was then of beneficial effect, a maximum value of 44% for indicated thermal efficiency being obtained as compared to a maximum of 42.5% without it. The experimental results are interpreted in the light of combustion tube experiments showing that hydrogen in mixtures with air is not ignited by red hot surfaces on which it is oxidized with sufficient rapidity to steam, but that ignition occurs at relatively low temperatures if the surface reaction is inhibited by hydrogen sulphide. The conclusion is that fuel gases containing hydrogen in large proportion can be used for full power engine operation at compression ratios even higher than 12: 1 if the oxidation of the hydrogen in part to steam, on the hot surfaces in the combustion chamber, is not inhibited by the poisoning effect of the hydrogen sulphide commonly present in the gases.
THE CURVE COMPUTER
Authors: Middleton W. E. Knowles
Published: April 2011

An electromechanical instrument has been developed, which adds, subtracts, multiplies, or divides the ordinates of two curves in Cartesian co-ordinates, plotting the resulting locus. This uses the principle of the Wheatstone bridge, and is semiautomatic; the curves are followed manually, but a phase-sensitive servo system keeps the bridge in balance. Attachments are provided for determining the area under the resulting curve, and also for the performance of certain logarithmic operations of interest in photometry. In the ordinary use of the computer, the accuracy is about 0.3% of full scale or better.
THE EFFECT OF CITRIC ACID UPON THE OXIDATION OF PEANUT OIL AND OF THE METHYL ESTERS DERIVED FROM PEANUT OIL
Authors: Lemon H. W. , Knapp Ruth M. , Allman A. H.
Published: April 2011

Addition of 0.005–0.500% citric acid to refined peanut oil caused a marked retardation of the oxygen absorption by the oil at 100 °C. Conversely, oxygen absorption was accelerated by the addition of from 0.11 to 10.00 p.p.m. iron in the form of iron stearate. When iron and citric acid were added together, the accelerating effect of iron on oxidation was overcome when the molar ratio of citric acid to iron was about 23:1; with higher concentrations of citric acid, oxidation was retarded still further.With distilled methyl esters of the fatty acids of peanut oil, further purified by passage through a column containing activated carbon, citric acid addition alone had only a small effect. Addition of iron caused acceleration of oxygen absorption which was compensated for by suitable addition of citric acid. Addition of hydroquinone caused a retardation of oxygen absorption, and still further retardation occurred when citric acid and hydroquinone were added together. It was concluded that citric acid has the properties of both a metal deactivator and a synergist, but does not in itself function as an antioxidant.
A Note on the Fate of Betaine Hydrochloride in Media Used for the Production of 2,3-Butanediol by Strains of Bacillus polymyxa
Authors: Murphy Diarmuid
Published: April 2011

not available
Integrating across scales: effectively applying science for the successful conservation of Atlantic salmon (Salmo salar)
Authors: Mather Martha E , Parrish Donna L , Folt Carol L , DeGraaf Richard M
Published: April 2011

Atlantic salmon (Salmo salar) is an excellent species on which to focus synthetic, integrative investigations because it is an economically important species that captures the public imagination, is heavily impacted by humans, uses several ecosystems over its life, and is the subject of a large body of extant literature. The following 24 papers were solicited to provide the biological basis for effective and innovative approaches that biologists, managers, and social scientists can use to develop policies that sustain Atlantic salmon and related species. Together these papers highlight the need for and benefits of (a) synthesizing within populations, (b) choosing the appropriate scale, (c) comparing across populations using rigorous, focused, question-oriented methods, (d) integrating across disciplines, (e) incorporating the human perspective, (f) linking multiple ecosystems, and (g) applied problem solving. To show how Atlantic salmon can guide research and conservation efforts for other species in other systems, we review the justification for the supplement and summarize the defining concepts that emerge from the volume.
Potential-field signatures of buried Precambrian basement in the Western Canada Sedimentary Basin
Authors: Pilkington M , Miles W F , Ross G M , Roest W R
Published: April 2011

An internally consistent, levelled compilation of magnetic data is derived for Alberta and northeastern British Columbia. With Bouguer gravity data, this compilation is used to refine the definition of Precambrian basement domains within the Western Canada Sedimentary Basin. Magnetic data are draped at a constant distance above the mapped basement surface to reduce the effects of varying magnetic source depths. Automated interpretation methods that effectively map outlines of magnetic sources are used to characterize the internal structure of the domains and to aid in their delineation. The basement domain map thus derived differs from previous interpretations in the extension of domains further to the southwest, due mainly to the availability of new public-domain magnetic data and the more precise definition of domain boundaries, based on the magnetic source location maps. The Nahanni, Hottah, Chinchaga, Thorsby, Vulcan, and Kiskatinaw domains are weakly magnetic and characterized by magnetic sources that are paramagnetic, comprising low-susceptibility silicate minerals. All other domains are characterized by the presence of ferrimagnetic material, most likely magnetite, which has a sufficiently high susceptibility to produce measurable anomalies. The largest anomalies and magnetizations are found in the Fort Nelson, Fort Simpson, Buffalo Head, Talston, Ksituan, and Matzhiwin domains. Such large magnetizations are usually indicative of intermediate igneous rocks associated with magmatic arc environments. Moderate-amplitude anomalies and (or) magnetizations are characteristic of the Nova, Wabamun, Lacombe, Rimbey, Loverna, and Medicine Hat domains, suggesting the presence of ferrimagnetic basic and granitoid rocks. Within some of the moderately magnetic domains are areas of paramagnetic lithologies that produce no magnetic anomalies. The narrower regions of magnetic lows, such as the Thorsby, Kiskatinaw, and Vulcan domains, are interpreted as resulting from demagnetization effects accompanying collision. Since demagnetization zones are limited in areal extent, the wider, more extensive magnetic lows of the Chinchaga and Hottah domains likely result from a combination of boundary demagnetization and a lower bulk magnetization level of crustal lithologies present.
Cretaceous-Tertiary palynofloral perturbations and extinctions within the Aquilapollenites Phytogeographic Province
Authors: Sweet A R , Braman D R
Published: April 2011

A combination of detailed, intermediate and large scale stratigraphic perspectives is necessary to understand the driving mechanisms for floral change across the Cretaceous-Tertiary (KT) boundary, because short-term physical and biotic events occur within longer term trends. Most Maastrichtian palynofloral extinctions have been identified within the northern circumpolar, supra-continental, Aquilapollenites Province. In mid-continental North America, the presence of a physically defined KT boundary provides opportunities to examine contemporaneous terrestrial palynofloras over a latitudinal (also approximately paleolatitudinal) distance of 3200 km. Seventy-five percent of last appearances occur before the KT boundary at high latitudes and must have been caused by ongoing terrestrial processes. Palynofloral events directly associated with the KT boundary include both local last appearances, and inferred extinctions, and synchronous and diachronous changes in relative abundances. Two different styles of factors are reflected in these events. The first, possibly attributable to chemical or other profound atmospheric perturbations associated with the worldwide distribution of the "fireball" layer of the KT claystone, resulted in extinctions of angiosperm with a zoophilous pollination strategy. The second factor, possibly reflecting energy released during the deposition of ballistically transported impact debris or hackly (ejecta) layer of the boundary claystone, resulted in the selective, northward-attenuating removal of the canopy vegetation, best documented for southwestern Canada, which was succeeded by a fern-dominated vegetation in mid-continental North America. These consequences of the boundary event were mediated by independent, preexisting circumstances: climate (regional and through time), local depositional environment, and ongoing background extinctions and origins.
The July 29, 1998, debris flow and landslide dam at Capricorn Creek, Mount Meager Volcanic Complex, southern Coast Mountains, British Columbia
Authors: Bovis Michael J , Jakob Matthias
Published: April 2011

A very large debris flow was triggered during a period of record-breaking high temperatures in upper Capricorn Creek, within the Mount Meager Volcanic Complex, a part of the Garibaldi Volcanic Belt of the southern Coast Mountains. The debris flow deposit impounded Meager Creek, creating an 800 m long landslide-dammed lake. The total event volume was 1.2 × 106 m3. The debris flow was followed by three days of almost continuous hyperconcentrated flow surges, which caused significant fluvial aggradation in the Meager Creek flood plain below the Capricorn Creek confluence. Within a few days of the formation of the landslide dam, a spillway notch had been cut through the deposit, thereby preventing the occurrence of a catastrophic dam break. The landslide, which triggered the debris flow, originated in deep volcanic colluvium having a previous history of progressive slope deformation, a consequence of glacial downwasting since the Neoglacial maximum. This paper highlights an important landslide response to recent glacial retreat and suggests that similar events could reoccur within Capricorn Creek, as well as at other sites where steep colluvial and weak bedrock slopes have been glacially debuttressed.
Modélisation d'un système karstique complexe (bassin de St-Chaptes, Gard, France) : un outil de synthèse des données géologiques et hydrogéologiques
Authors: Josnin Jean-Yves , Pistre Séverin , Drogue Claude
Published: April 2011

Numerous software packages allow the efficient modeling of the hydrodynamic behaviour of aquifers in continuous media. To study pressure transfer in discontinuous media like karsts, the black-box models are restrictive and the models that consider discrete conduit networks are unsuitable for reservoir scale. We show that the utilization of a continuous media model can lead to useful results, even in the case of complex systems, but needs to be adapted to karst specificity. The problem is approached by studying a hydrogeological system located in the Mediterranean Languedoc region: the St-Chaptes basin. This system consists of three superposed aquifers included in four different stratigraphic series. The main aquifer is a karst formation in contact with two other karst formations that belong to different hydrogeologic systems. Considering geological data in addition to hydrological data and with the hypothesis of a relative homogenization of the karst's hydraulic behaviour on a large spatial scale for daily to monthly increments, the model that takes into account the relations with the other aquifers allows (i) a preliminary identification of the main heterogeneities inside the reservoir; (ii) the location of barriers and low-permeability zones that isolate some parts of the aquifer; (iii) the observation of a curious behaviour of the piezometric levels in the confined zones of the aquifer; and (iv) the characterization of the exchanges with the other low-volume but existing aquifers.
Middle Pleistocene to Holocene palynostratigraphy of Ocean Drilling Program Site 887 in the Gulf of Alaska, northeastern North Pacific
Authors: Marret Fabienne , Vernal Anne de , Pedersen Thomas F , McDonald Darcy
Published: April 2011

A palynological investigation was undertaken on the upper 29 m of sediment at Ocean Drilling Program (ODP) Site 887, spanning the last 430 000 years (i.e., isotopic stages 12 to 1). Pollen and dinocyst assemblages reveal a major ecostratigraphical boundary at the MiddleLate Pleistocene transition. The Middle Pleistocene pollen data document the occurrence of a spruce forest vegetation in the source area, likely located on the adjacent Alaskan coast, whereas the Late Pleistocene is marked by higher inputs of pine, shrub, and herb taxa, suggesting predominant inputs from a more open landscape. The Middle Pleistocene is characterized by a low diversity in dinocyst assemblages, which are dominated by Operculodinium centrocarpum, whereas the Late Pleistocene is marked by the significant occurrence of Pentapharsodinium dalei, Pyxidinopsis reticulata, and by high percentages of Brigantedinium spp. Such assemblages suggest open oceanic and cool temperate conditions during the Middle Pleistocene, changing toward generally colder and less saline conditions during the Late Pleistocene. In addition, large fluctuations in the dinocyst assemblages during the Late Pleistocene are recorded in phase with the main shifts in the isotopic stratigraphy. A new dinocyst taxon, Spiniferites alaskensis sp. nov., exclusively recorded in sediments of the isotopic substage 5e, is described herein.
Magmatic evolution of the southern Great Bear continental arc, northwestern Canadian Shield: geochronological constraints
Authors: Gandhi S S , Mortensen J K , Prasad N , Breemen O van
Published: April 2011

The calc-alkaline Great Bear continental arc in the Wopmay Orogen developed after a collision ca. 1890 Ma of the Archean Slave craton with the Paleoproterozoic Hottah terrane to the west. UPb zircon dating of three volcanic and six intrusive rocks from the southern part of the arc shows four stages of development: (i) intrusion of a few small sodic leucogranite plutons at 1873 ± 2 Ma into a previously folded metasedimentary sequence; (ii) abundant calc-alkaline felsic volcanism and subvolcanic intrusions during the period 18701866 Ma, bracketed by five ages; (iii) intrusion of large calc-alkaline granitic plutons, including the Marian River batholith, dated by zircon and titanite from two samples at 1866 +23 Ma; and (iv) emplacement of the potassic Faber Lake rapakivi granite at 1856 +23 Ma. The arc was developed on the Hottah terrane due to easterly subduction of an oceanic plate under the amalgamated Slave craton  Hottah terrane. The oldest exposed rocks in the southern part of the arc are remnants of a Paleoproterozoic platformal sequence. They were regarded previously as equivalents of the initial passive margin sequence on the Slave craton, but are interpreted here as part of the Hottah terrane. The ages reported here are comparable with earlier data from the northern part of the arc, which show an age range from 1875 to 1840 Ma and also identify two suites of compositionally and temporally distinct granites. The age constraints show that the Great Bear arc evolved rapidly in time from sodic through calc-alkaline, and then, with a pause, to potassic composition.
Lithostratigraphy and limiting optical ages of the Pleistocene fill in Fraser River valley near Clinton, south-central British Columbia
Authors: Lian Olav B , Hicock Stephen R
Published: April 2011

The Fraser River valley near Clinton contains a thick sediment fill that is presently incised down to bedrock. The sequence, approximately 500 m thick, is generally upward fining and consists of up to 100 m of glacigenic debris flow diamicton and glaciofluvialdeltaic gravel and sand at the base, overlain by about 350 m of glaciolacustrine sediments and minor diamicton, which is in turn capped by several metres of till. The sequence is interpreted to represent (i) valley aggradation in response to glaciation, followed by (ii) the impoundment of the valley by sediment and (or) ice, and the formation of a large proglacial lake(s), and finally (iii) overriding of the valley fill by glaciers. This glacial advance sequence can be readily correlated with previously studied units situated immediately to the north, most of which have been associated with the last glaciation; however, the age of these units has been based only on stratigraphic relations. We introduce limiting optical ages from a widespread glaciolacustrine unit that show that the glacial advance sequence was formed, at the earliest, during the penultimate Okanagan Centre Glaciation (oxygen isotope stage 4; ca. 7459 ka), but almost certainly during the (last) Fraser Glaciation (oxygen isotope stage 2; ca. 2412 ka). It could not have been deposited during oxygen isotope stage 6, or during an older glaciation.
Enhanced resolution of geological structures from magnetic data: an example from the Abitibi Greenstone Belt of Northern Ontario
Authors: Prevec Ludvik , Morris William A
Published: April 2011

Structural information about that portion of the economically important DestorPorcupine Deformation Zone and its associated faults, which lie buried under many metres of Clay Belt sediments in the region north of Matheson, Ontario, must rely principally on interpretation of geophysical data. In this area, the Archean greenstones of the Abitibi are crosscut by at least three generations of strongly magnetic diabase dykes. The predominant dyke set, the Matachewan, trend northsouth, orthogonal to structures in the greenstones. Directional horizontal derivative analysis of the total magnetic field, which has a much sharper angular cutoff than that provided by standard Fourier-based filters, provides a method for separating the magnetic contributions from these two sources. This analysis revealed the existence of a previously unidentified fault (the Winslow fault) located to the north of, and parallel to, the economically significant Pipestone Fault. We also define a second new fault, the Carr fault, that is intimately associated with the existence of a buried felsic intrusive complex in Carr Township. Possible associations between these faults and previously known faults defined from surface mapping programs are explored.
Holocene and latest Pleistocene fluctuations of Stutfield Glacier, Canadian Rockies
Authors: Osborn G D , Robinson B J , Luckman B H
Published: April 2011

The Holocene and late glacial history of fluctuations of Stutfield Glacier are reconstructed using moraine stratigraphy, tephrochronology, and dendroglaciology. Stratigraphic sections in the lateral moraines contain tills from at least three glacier advances separated by volcanic tephras and paleosols. The oldest, pre-Mazama till is correlated with the Crowfoot Advance (dated elsewhere to be Younger Dryas equivalent). A Neoglacial till is found between the Mazama tephra and a paleosol developed on the Bridge River tephra. A log dating 2400 BP from the upper part of this till indicates that this glacier advance, correlated with the Peyto Advance, culminated shortly before deposition of the Bridge River tephra. Radiocarbon and tree-ring dates from overridden trees exposed in moraine sections indicate that the initial Cavell (Little Ice Age (LIA)) Advance overrode this paleosol and trees after A.D. 1271. Three subsequent phases of the Cavell Advance were dated by dendrochronology. The maximum glacier extent occurred in the mid-18th century, predating 1743 on the southern lateral, although ice still occupied and tilted a tree on the north lateral in 1758. Subsequent glacier advances occurred ca. 18001816 and in the late 19th century. The relative extent of the LIA advances at Stutfield differs from that of other major eastward flowing outlets of the Columbia Icefield, which have maxima in the midlate 19th century. This is the first study from the Canadian Rockies to demonstrate that the large, morphologically simple, lateral moraines defining the LIA glacier limits are actually composite features, built up progressively (but discontinuously) over the Holocene and contain evidence of multiple Holocene- and Crowfoot-age glacier advances.
A new species of Chasmosaurus (Dinosauria: Ceratopsia) from the Dinosaur Park Formation of southern Alberta
Authors: Holmes Robert B , Forster Catherine , Ryan Michael , Shepherd Kieran M
Published: April 2011

Chasmosaurus irvinensis (sp. nov.) is distinguished from other species of this genus by the possession of a broad snout, absence of a brow horn (the position of which is occupied by a pit or rugosities suggestive of bone resorption), broadly rounded and open jugal notch, subrectangular squamosal, straight posterior parietal bar bearing 10 epoccipitals, eight of which are flattened, strongly curved anterodorsally, and nearly indistinguishably coossified to their neighbours, and small, transversely oriented parietal fenestrae restricted to the posterior portion of the frill. This species, restricted to the upper part of the Dinosaur Park Formation, is significantly younger than the other recognized Canadian Chasmosaurus species, C. belli and C. russelli. Phylogenetic analysis shows that C. irvinensis is most closely related to the other Canadian Chasmosaurus species and more distantly related to Chasmosaurus mariscalensis from Texas.
Low-temperature cooling history of the Shuswap metamorphic core complex, British Columbia: constraints from apatite and zircon fission-track ages
Authors: Lorencak M , Seward D , Vanderhaeghe O , Teyssier C , Burg J P
Published: April 2011

Nine zircon and 18 apatite fission-track ages are used to determine the low-temperature cooling history of part of the Shuswap metamorphic core complex of the Canadian Cordillera. The zircon ages range from 54 to 38 Ma and the apatite ages from 49 to 28 Ma. These ages reveal a similarity in cooling histories across the Shuswap units until temperatures of ~250°C were reached at about 45 Ma. From this time onwards, the regional cooling pattern within the core complex was controlled by the relative movements on two normal faults, the Victor Creek fault and the Columbia River fault. Cooling since 45 Ma was variable, depending on the structural level of the sample. On this basis four thermotectonic units are defined. These units are controlled by normal faults that crosscut the lithological units of the core complex and reflect the latest stage of its evolution.