bluuebunny/crossref_metadata_2025 huggingface dataset:
THE MECHANISM OF OXYMERCURATION OF ALKENES
Authors: Brook A. G. , Wright George F
Published: April 2011

A factual test of several possible mechanisms by which alkenes are oxymercurated shows that while addition of mercuric acetate to cyclohexene can be effected smoothly, this 1-acetoxy-2-acetoxymercuricyclohexane cannot be an intermediate in the conversion of cyclohexene in methanolic mercuric acetate to 1-methoxy-2-acetoxymercuricyclohexane. The rate at which the first compound is converted to the second in methanol is much too slow to account for the rate of methoxymercuration. Indeed the behavior of conversion indicates that the first compound reverts in methanol to cyclohexene which then combines with the elements of methoxymercuric acetate. Ionic mechanisms have been shown to be untenable since hydroxymercuration is slower than methoxymercuration although it occurs in a solvent which is much more polar than methanol. A co-ordinative dipole mechanism is suggested which explains the complete retention of configuration during addition as well as the function of boron trifluoride as an accelerator in this reaction.
STUDIES ON EXPLOSIVE ANTIMONY: IV. THE HEAT OF EXPLOSION AT 40 °C.
Authors: Coffin C. C. , Hubley C. E.
Published: April 2011

The heat of the "explosive" crystallization of electrolytically deposited amorphous antimony has been directly determined at 40 °C. in a modified Bunsen-type calorimeter using benzalacetone as the working substance. Correction was made for the amount of antimony trichloride in the deposits and for the crystallization that had taken place between their preparation and explosion. Sixteen runs on exceptionally uniform specimens containing between 4.0 and 7.9% antimony trichloride gave 21.8 cal. per gm. for the heat of explosion, which thus appears to be independent of the antimony trichloride content.
A MICROMETHOD FOR THE DETERMINATION OF SUGARS
Authors: Stone J. E. , Blundell M. J.
Published: April 2011

Certain pentoses and hexoses were determined by measuring spectrophotometrically the yields of furfural and hydroxymethylfurfural obtained on steam distilling with syrupy phosphoric acid. The yields, based on the theoretical recovery, were increased by increasing the temperature and the rate of steam distillation, and by decreasing the amount of sugar. At a steam rate producing 10 ml. per min. of distillate, at 195 °C. externally applied temperature, and with 2 mgm. sugar, the yields of aldehyde were from xylose 91.0%, ribose 74.9%, arabinose 60.6%, rhamnose 55.9%, galactose 20.0%, and glucose 15.5%. As little as 0.1 mgm. of each could be determined in this way, the mean deviation being usually less than ± 3% and the time required less than 10 min. Mixtures of sugars have been separated on a paper strip chromatogram and the individuals determined, without separate extraction, by steam distilling into phosphoric acid.
THE PREPARATION OF 1-ALKOXY-1,3-BUTADIENES BY PYROLYSIS OF TRIALKOXYBUTANES: II. CIS- AND TRANS-1-METHOXY-, 1-ETHOXY-, AND 1-n-PROPOXY-1,3-BUTADIENES
Authors: Farmilo Charles G. , Nicholls R. V. V.
Published: April 2011

The acetals, 1,1,3-trimethoxybutane, 1,1,3-triethoxybutane, and 1,1,3-tri-n-propoxybutane have been pyrolyzed by passage over a synthetic barium silicate at various temperatures. The yields of the 1-alkoxy-1,3-butadienes isolated from the products of pyrolysis were 80, 45, and 36% respectively. A limited number of catalysts of compositions varying from BaO: 2SiO2 to BaO: 10SiO2 have been prepared, including the recommended, BaO: 5SiO2. The qualitative effect of catalyst composition of some of these silicates on the yield of 1-methoxy-1,3-butadiene has been described. trans-1-Methoxy-1,3-butadiene has been isolated and characterized by means of reactions with maleic anhydride, and a solution containing cis and trans molecules has been analyzed and shown to contain 60% cis-1-methoxy-1,3-butadiene.
STUDIES ON RDX AND RELATED COMPOUNDS: I. THE DIRECT NITROLYSIS OF HEXAMINE TO RDX
Authors: Vroom A. H. , Winkler C. A.
Published: April 2011

Maximum yields, of about 40%, of RDX were obtained with nitric acid of all concentrations down to 88%, providing the molar ratio of nitric acid to hexamine was sufficiently high. The rate of nitrolysis increased rapidly as the molar ratio of nitric acid to hexamine was increased and continued to do so after the molar ratio was raised above that required for maximum yields. The initial rate was shown to have an upper limit, however, at very high molar ratios. An intermediate in the nitrolysis reaction was isolated and identified as 3,5-dinitrocyclotrimethylenetriamine-1-nitrate (I). (I) was formed rapidly in sufficient quantities of 85 to 91% nitric acid at 0 °C., but had a high rate of decomposition which was independent of both acid concentration and ratio of nitric acid to (I) with 80 to 90% nitric acid. Under nitrolysis conditions some of the hexamine was converted to products not capable of giving RDX, owing apparently to hydrolysis of precursors to (I). The activation energy for the conversion of (I) to RDX was found to be identical with that for the rate controlling step of the conversion of hexamine to RDX. This fact, together with the general kinetic behavior of (I), provided evidence that (I) was a true intermediate and that its reaction to RDX was the rate controlling step in the direct nitrolysis of hexamine. The mechanism of the over-all reaction is discussed in relation to published information concerning the constitution of concentrated nitric acid. Nitracidium ion is believed to be the active nitrolyzing agent.
STUDIES ON RDX AND RELATED COMPOUNDS: II. THE NITROLYSIS OF HEXAMINE IN ACETIC ACID
Authors: Winkler C. A. , Kirsch M.
Published: April 2011

Acetic acid has a harmful effect on the reaction rate and on the yield of RDX at 1 °C. and at 30 °C. for a given nitric acid – hexamine ratio below a certain optimum value. At the optimum, however, the maximum yield of 80% is obtained at both temperatures. The deleterious effect of acetic acid may be explained by assuming that the concentration of the active nitrolyzing agent (nitracidium ion) is decreased by reaction between acetic acid and nitric acid.
VOLUMETRIC DETERMINATION OF SMALL AMOUNTS OF IRIDIUM
Authors: McBryde W. A. E. , Cluett M. L.
Published: April 2011

A volumetric procedure is described for determining small amounts of iridium (from 2 to 20 mgm.). A solution of the metal is heated to dense fumes with sulphuric acid, cooled, diluted with water, and then oxidized with an excess of cerium (IV) sulphate solution. The resultant solution is titrated with a standard 0.01 N iron (II) sulphate solution, the course of the titration being followed potentiometrically. In solutions containing other platinum metals it has been found possible to determine iridium directly in some cases by this procedure; in other cases it was found necessary to remove osmium as the volatile tetroxide prior to oxidizing with cerium (IV) sulphate. The method is probably less accurate than existing gravimetric procedures, but offers considerable advantage in simplicity.
STUDIES ON THE PARASITISM AND VARIATION OF ALTERNARIA RAPHANI
Authors: Atkinson R. G.
Published: April 2011

The natural infection of radish seed with A. Raphani may result in a lack of germination, a pre- or postemergence blight, a distinctive lesioning of cotyledons and hypocotyls, the presence of scablike lesions on table radish, and in the spotting and blighting of leaves, stalks, and siliques. The fungus was isolated from the internal tissues of all parts of dormant radish seed. Although the pathogen has been reported only on radish in Canada and the United States, the present investigation shows that Canadian isolates are capable of causing a severe leaf blight of stocks and wallflowers. Under field conditions at St. Catharines, Ont., most rapid progress of the disease occurred at temperatures within the optimum range for the fungus, i.e., 22° to 26 °C. Experimental evidence suggests that A. Raphani does not establish an overwintering inoculum in the soil by means of diseased plant debris. Increased soil moisture was associated with increased seedling disease. At a high soil moisture content, infection was lowest at 18 °C.; at medium soil moisture, it was lowest at 18 °C. and also at 23 °C., the next highest experimental temperature.Monosporous isolations showed the presence of numerous wild type strains of A. Raphani which were closely related culturally. Five of these studied intensively differed widely in virulence and sporulation, but had similar growth rates and nutritional requirements for maximum growth. Although most isolates of A. Raphani produced only a few spores in ordinary agar cultures, abundant sporulation was obtained by wounding plate cultures and removing the lids of the culture plates. In agar culture, the wild types readily produced mostly appressed variant strains also showing close cultural relations. These variants exhibited wide differences in pathogenicity, rate of growth, and nutritional requirements, but all showed practically complete loss of sporulation either in normal or wounded cultures. The effects of cultural variation of wild type strains on cultural habit, pathogenicity, rate of growth, sporulating capacity, and nutritional requirements were random and unrelated. These data, as well as the spontaneous origin and irreversibility of the variants, favored the view that they arose in culture by mutation in the naturally occurring strains.A. Raphani was shown to be capable of surviving at least 18 months in dry soil cultures with no loss of cultural habit, virulence, or sporulation.Appreciable increase in emergence and decrease in seedling infection was obtained by seed treatments with some of the common fungicidal dusts.
EFFECT OF PASMO DISEASE ON SEED YIELD AND THOUSAND KERNEL WEIGHT OF FLAX
Authors: Sackston W. E.
Published: April 2011

The pasmo pathogen sporulated freely on potato dextrose agar containing yeast extract. Spores suspended in water with gelatin as a spreader–sticker were sprayed onto flax plants at different stages of growth in field plots. Heaviest infections of pasmo resulted from inoculations at the flowering stage, lighter infections from inoculations on seedlings, and lightest infections from inoculations on ripening plants. Diluting the concentration of spores in the inoculum reduced disease intensity. The four flax varieties in the tests differed in reaction to pasmo. In decreasing order of susceptibility they were: Viking, Redwing, Royal, and Crystal. Heavy infections of pasmo caused premature ripening and reduced the seed yield and weight per thousand kernels of all four varieties. The effects of pasmo infection on seed yield and kernel weight were similar to those caused by a hot, dry climate, and by flax rust. Seed yield and kernel weight were reduced most markedly by inoculation at the flowering stage, less severely by inoculation at the seedling stage, and least of all by inoculation at the time of ripening. Seed yield and kernel weight from plots inoculated when the plants were ripening did not differ significantly from the uninoculated checks. Highly significant positive correlations between the data for seed yield and kernel weight indicated that much of the loss in yield resulted from a reduction in the size of individual seeds.
STORAGE OF ISOLATED CHLOROPLASTS WITHOUT LOSS OF PHOTOCHEMICAL ACTIVITY
Authors: Gorham P. R. , Clendenning K. A.
Published: April 2011

Fragmented spinach chloroplasts were stored for one year in 0.5 M sucrose at −40 °C. with almost negligible losses of photochemical activity. Thawed chloroplasts and freshly isolated chloroplasts showed similar rates of deterioration at 10 °C. Washed chloroplasts did not show as high retention of activity during low temperature storage as crude chloroplast suspensions. High retentions of activity were observed with chloroplasts from different plant species, as well as with different oxidants. The activities of subsamples that were frozen and thawed in a standard way agreed within 5%. Deterioration during lyophilization of chloroplasts occurred chiefly during the early stages of drying, and was lessened by sucrose. The stability of lyophilized chloroplasts in storage varied directly with the degree of desiccation and inversely with the storage temperature; little deterioration occurred in thoroughly dried chloroplasts during lengthy storage at or below 5 °C.
STUDIES OF COPROPHILOUS ASCOMYCETES: I. GELASINOSPORA
Authors: Cain Roy F.
Published: April 2011

Two species of Gelasinospora are described for the first time. G. adjuncta Cain, a heterothallic species with eight-spored asci, was grown in moist chambers on dung from Germany and Quebec. G. retispora Cain, distinguished by means of the large angular pits in the ascospore wall was isolated in culture from seeds of Swiss chard from Holland and from apple twigs in Quebec. G. tetrasperma Dowding has been found in moist chambers on dung from Ontario, Quebec, Venezuela, and Germany and isolated from seeds from Quebec. Notes are added regarding the disposition of Anthostomella destruens Shear and Sordaria uvicola Viala and Marsais.
THE PROTEOLYTIC ENZYMES OF MICROORGANISMS: III. SOME CHARACTERISTICS OF EXTRACELLULAR PROTEASES PRODUCED IN SUBMERGED CULTURE
Authors: McConnell W. B.
Published: April 2011

Some of the general characteristics of the proteases liberated into the culture medium by molds and actinomycetes grown in submerged culture have been studied. Species of Alternaria, Streptomyces, Mortierella, and Gliocladium were used. The enzymes resemble trypsin in that they are most active at a pH slightly above 7 and are inhibited by a preparation of egg albumin. They are stable at low temperatures but suffer marked losses in activity when stored for 16 hr. above 40 °C. The most rapid hydrolysis of gelatin occurs at temperatures between 40 °C. and 50 °C. The enzymes from different organisms show definite differences with respect to their ability to attack different proteins, gelatin and casein being in general the most readily digested. The protease systems from different organisms also vary with respect to the extent to which they can digest gelatin; some enzymes are able to release about three times as many amino groups from gelatin as others. The limit of the hydrolysis is not dependent upon substrate concentration but is slightly affected by the concentration of enzyme. The enzymes were effective in liberating free amino acids from gelatin.
CARBONIC ANHYDRASE IN GREEN PLANTS
Authors: Waygood E. R. , Clendenning K. A.
Published: April 2011

Carbonic anhydrase was found in leaf extracts prepared from 19 of 22 land and aquatic plant species examined. The most active preparations were obtained from Spinacia oleracea L., Tetragonia expansa Thunb., Tropaeolum majus L., and Sambucus canadensis L. Carbonic anhydrase is located in the leaf cytoplasm. Previously conflicting observations concerning its intracellular localization have been reconciled experimentally. Plant carbonic anhydrase is strongly inhibited by M/1000 azide, M/1000 cyanide, and M/2000 sulphanilamide and is weakly inhibited by 2,4-dichlorophenoxyacetic acid, diethyldithiocarbamate, and o-phenanthroline. The white zones of variegated Tradescantia leaves contain 50% less carbonic anhydrase than their green counterparts. Albino barley leaves contain 75% less carbonic anhydrase than normal barley leaves of the same size and age. The carbonic anhydrase content of green leaves kept in darkness for four and five days was lowered by 30–50%. Very young leaves contain less enzyme than mature leaves. These results are discussed in relation to the possible role of carbonic anhydrase in photosynthesis.
OBSERVATIONS ON THE BIONOMICS OF SOME NORTHERN MOSQUITO SPECIES (CULICIDAE: DIPTERA)
Authors: Hocking B. , Richards W. R. , Twinn C. R.
Published: April 2011

The species of mosquitoes now known to occur at Churchill, Man., are listed and include 12 species of Culicinae and four of Chaoborinae. Evidence is advanced that one of these, Aedes communis DeG., may really be two species; and a method is suggested of separating some of the black-legged species of Aedes without using larval characters or scaling. Some observations on larval habits and habitats, seasonal development, species associations, temperature relationships, and natural enemies are given. Rearing methods used in the field and in the insectary are described. Seasonal changes in numbers, species composition, and activity of the adult population are studied, and quantitative estimates of the influence of meteorological factors on activity are made. Mating habits are described, and adult feeding habits, both on nectar and on blood, are discussed and illustrated. Observations on the development and number of eggs of some species are recorded.
DEPOSITION OF P32 IN DEVELOPING DROSOPHILA
Authors: Irwin R. L. B. , Spinks J. W. T. , Arnason T. J.
Published: April 2011

Eggs of Canton Special stock of Drosophila were hatched and larvae reared on medium containing P32. Alternate radioautographed and stained sections were made of larvae, pupae, and adults. Deposition of P32 was found to be heavy in fat bodies, nervous structures, and in organs of digestion and excretion. Very high concentrations of P32 occurred in imaginal discs. Discharged materials and nuclei from fat bodies had much P32 in early pupal stages, the activity becoming concentrated at sites of organ differentiation in later pupae. In the adults, the gonads, the nervous system, and the digestive tract contained much P32.
PHYSICAL AND BIOLOGICAL INDICATORS OF THE DEVELOPMENT OF OUTBREAKS OF THE SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (CLEM.) (LEPIDOPTERA: TORTRICIDAE)
Authors: Wellington W. G. , Fettes J. J. , Belyea R. M. , Turner K. B.
Published: April 2011

Biological and meteorological records were examined for periods when outbreaks of the spruce budworm, Choristoneura fumiferana (Clem.), were known to have occurred in northeastern North America. The survey showed that the following significant events occurred during the period of three to four years preceding an outbreak. Decreasing annual numbers of low pressure centers passed over the area in which the outbreak later occurred. Therefore, the outbreak began at a time of decreased or minimal storminess. Drought occurred, chiefly in June and July, but also occasionally in spring and autumn. Annual increments of host trees on dry sites declined. Outbreaks of the forest tent caterpillar, Malacosoma disstria Hbn., occurred, particularly in Ontario. These events, in aggregate, occurred so consistently before spruce budworm outbreaks that they have future predictive value. In addition, they reinforce some suggestions made by earlier authors and suggest modifications of hypotheses concerning the behavior of developing populations of the spruce budworm.
THE MULTIPLICATION OF INSECT VIRUSES AS ORGANISMS
Authors: Bergold G. H.
Published: April 2011

Electron micrographs of purified preparations of four different insect viruses indicate the presence of morphologically different forms, which are probably stages of multiplication. The virus first appears as a minute spherical body. This body increases in size and the virus appears as an elongated, curved body, surrounded by a membrane. Later the virus particle straightens out, ruptures the membrane, and appears as a rod-shaped particle characteristic of insect viruses. One may assume that the rod-shaped virus particle contains several smaller subunits each of which develops into a rod. The complicated nature of multiplication indicates that insect viruses are organisms with a relatively simple morphological structure of the mature rod.
ALKALINE AND ACID PHOSPHATASE IN CEREBROSPINAL FLUID: DATA FOR NORMAL FLUIDS AND FLUIDS FROM PATIENTS WITH MENINGITIS, POLIOMYELITIS, OR SYPHILIS
Authors: Colling K. G. , Rossiter R. J.
Published: April 2011

Many normal cerebrospinal fluids contain an alkaline (pH 9.8) and an acid (pH 4.9) phosphatase. Both the alkaline and the acid phosphatase were significantly increased in the spinal fluids from patients with meningitis or poliomyelitis, but not in the fluids from patients with syphilis. The alkaline phosphatase activity was correlated with both the concentration of protein in the spinal fluid and with the white cell count, whereas the acid phosphatase was correlated with neither. When correction was made for the significant correlation between cell count and protein concentration, the partial correlation between alkaline phosphatase activity and both protein concentration and cell count remained significant statistically. In pathological conditions it appears likely that the alkaline phosphatase is derived partly from the polymorphonuclear leucocytes in the fluid and partly from the blood plasma. The acid phosphatase is probably derived from the lymphocytes of the fluid and possibly also from the blood plasma. It is unlikely that either of these enzymes comes from the substance of the brain or spinal cord. Acid phosphatase would be of more value than alkaline phosphatase as a diagnostic aid, since normal fluids contain much less of this enzyme.
THE UPTAKE OF RADIOACTIVE PHOSPHORUS BY INFLUENZA VIRUS A (PR8 STRAIN)
Authors: Graham A. F. , McClelland Laurella
Published: April 2011

Radioactive inorganic phosphorus placed in the allantoic sacs of embryonated eggs three hours after inoculation with influenza virus was incorporated into the structure of the virus during its growth. There was little or no direct exchange between the virus and radioactive inorganic phosphorus. The specific activity of purified labelled virus rose linearly with increasing amounts of radioactive phosphorus administered to the eggs. When radioactive phosphorus was placed in the allantoic sac 48 hr. before inoculation with influenza virus the newly formed labelled virus had a specific activity about 20% higher than when isotope was administered at the same time as virus. As the amount of isotope injected into each infected egg was increased up to 775 μrd. an increasing number of embryos died during the subsequent period of virus growth. The yield of virus from the surviving eggs was not less than from eggs which had not received radioactive phosphorus. Under the experimental conditions described the amount of isotope which could be introduced into influenza virus was not sufficient to permit the use of the marked virus in metabolism experiments in animals or embryonated eggs.
THE EFFICACY OF VARIOUS THIOLS AS ANTIDOTES TO LEWISITE
Authors: Simpson S. D. , Young L.
Published: April 2011

The following thiols were tested for their effectiveness in counteracting the systemic toxic action of lewisite (β-chlorovinyldichloroarsine) in the rat: 1- and 2-mercaptopropane, 2-mercaptoethanol, 1,2-dimercaptoethane, 1,2- and 1,3-dimercaptopropane, 1,2,3-trimercaptopropane, 1,2-dimercapto-n-butane, 2,3-dimercaptopropanol, 1,3-dimercapto-2-propanol, 2,2′-dimercaptodiethyl ether, 2,2′-dimercaptodiisopropyl ether, and 3,3′-dimercaptodipropyl ether. The toxicity and volatility of these compounds were also studied.The tests of antidotal activity were conducted by applying the thiol to the skin at a site which had been dosed with approximately twice the LD50 of lewisite. Under these conditions the monothiols gave no evidence of antidotal activity whereas all the dithiols and the trithiol studied showed some activity. 2,3-Dimercaptopropanol (BAL) and its isomer, 1,3-dimercapto-2-propanol, were much more effective as antidotes to lewisite than any of the other compounds tested. Not only did 2,3-dimercaptopropanol show a somewhat higher antidotal activity than its isomer, but it was also found to be much less toxic.
THE CHEMICAL ANALYSIS OF PURIFIED INFLUENZA VIRUS A (PR8 STRAIN) CONTAINING RADIOACTIVE PHOSPHORUS
Authors: Graham A. F.
Published: April 2011

Purified influenza virus A (PR8 strain) was found to contain about 11% phospholipid and 5% nucleic acid in agreement with previously reported work. The method of Schmidt and Thannhauser, applied to the nucleic acid fraction of the virus, indicated the presence of 4.5% pentose nucleic acid and 0.3% desoxypentose nucleic acid. When influenza virus was grown in the allantoic membrane of the embryonated egg in the presence of inorganic radioactive phosphorus both phospholipid and nucleic acid components of the virus were found to contain the isotope. The specific radioactivity of the nucleic acid fraction was about four times that of the phospholipid.
VIBRIO CHOLERAE IN FLUID MEDIA
Authors: Ranta L. E. , McLeod Mary
Published: April 2011

Studies have been made of the growth of V. cholerae in fluid media of chemically defined compositions. The addition of three amino acids, tyrosine, asparagine, and glycine, to a fluid medium containing inorganic salts produced a growth of V. cholerae equivalent to a 450 p.p.m. silica standard. Under conditions of aeration with an air and carbon dioxide mixture, yields comparable to the turbidity of a 1600 p.p.m. silica standard were obtained with a medium composed of 0.67 gm. of tyrosine, 0.42 gm. of asparagine, 0.51 gm. of glycine, 5.0 gm. of sodium chloride, 5.0 gm. of ammonium sulphate, 0.75 gm. of dipotassium hydrogen phosphate, 0.1 gm. of magnesium sulphate, 10.0 gm. of glucose, and 15.0 gm. of sodium bicarbonate dissolved in one liter of distilled water.
THE EFFECT OF OILING AND AIR CELL MOLD ON THE OXYGEN AND CARBON DIOXIDE CONTENTS OF THE AIR CELLS OF EGGS
Authors: Rose Dyson , Gibbons N. E.
Published: April 2011

The gas contained in the air cells of day old eggs had a high carbon dioxide content, but during storage the gas composition approached that of the surrounding atmosphere. Oiling of the egg, or otherwise sealing the shell, tended to retain carbon dioxide in the air cell. Growth of mold in the air cell, or of bacteria in the egg contents, markedly reduced the oxygen content and increased the carbon dioxide content of the air cell gas. Permeability of the shell of unoiled eggs to moisture vapor was low and the relative humidity in the air cell was shown to be 99% or higher. Oiling of the eggs cannot therefore promote mold growth by increasing the humidity in the air cell.
PRESERVATION OF EGGS: VII. EFFECT OF AGE OF EGG AND CARBON DIOXIDE CONTENT AT TIME OF OILING ON KEEPING QUALITY
Authors: Gibbons N. E.
Published: April 2011

The quality of eggs oiled when one day old is maintained better than that of eggs oiled when 6 or 10 days old, the ages between which most commercial eggs are treated. If the pH of the albumen of the older eggs is lowered by exposure to carbon dioxide before oiling (a simple method of treating eggs with carbon dioxide is described), the keeping quality as measured by yolk index, albumen height, and percentage of thick albumen is improved. However, these differences are not apparent on candling, and on this basis the improvement does not justify the added cost of the gassing treatment.
THE SUSPENDING POWER OF DETERGENT SOLUTIONS: I. PURE SOAPS
Authors: Weatherburn A. S. , Rose G. R. F. , Bayley C. H.
Published: April 2011

The ability of soaps to prevent the deposition of carbon black and other materials on fabric during the detergent process has been investigated. In general the suspending power of the soap solutions studied increased rapidly with increasing soap concentration, and reached a maximum at a relatively low concentration. At higher concentrations the suspending power either remained constant or decreased slightly. With carbonaceous soils the indicated suspending power for a given soap increased, in general, with increasing particle size and decreasing "structure" of the carbon. With various soiling materials differences were encountered, not only in the magnitude of the indicated suspending power, but also in the form of the curve obtained on plotting suspending power vs. soap concentration. As measured by one type of carbon black (Standard Micronex) only minor differences were found between suspending powers of sodium myristate, palmitate, and stearate, all of which were higher than that of the laurate. Increasing temperatures caused a decrease in the suspending power of the lower chain length soaps (C12, C14) and an increase in the suspending power of the longer chain soaps (C16, C18). The suspending power of sodium oleate was essentially unchanged by temperature variations over the range 25–80 °C.
FLUORIDE STUDIES RELATED TO THE HUMAN DIET
Authors: Ham Mary P. , Smith M. Doreen
Published: April 2011

Analyses of whole meals and beverages indicated that the amount of fluoride normally present in the adult diet is quite low but the ingestion of tea or high fluoride waters greatly increases it. The fluoride content of cow's milk from low and high water-fluoride areas was determined. Analyses of some baby foods showed that the fluoride content of certain cereals containing bonemeal is high. The influence on the infant diet of these cereals and of water and milk is illustrated.
THE MEASUREMENTS OF STRAINS IN TIRES
Authors: Loughborough D. L. , Davies J. M. , Monfore G. E.
Published: April 2011

Because of obvious complications it is too difficult to calculate the stresses in the cords of a tire. In this work the direct measurement of strains was undertaken. Two techniques will be discussed; (1) the measure of the increase in length of the cords in the outside ply, and (2) a radiographic technique in which the change in length of the cord elements, marked by steel wires, is followed by photographic methods. The measurements on a number of tires are presented. The cords in a tire are strained about 2% by the inflation pressure. When the tire is loaded some of the cords are thrown into compression and some into more tension. During the rotation of the tire the cords are thus subjected to a vigorous alternation of compression and tension (± 2%). At the same time the angles between the cords change by as much as two degrees. A few general applications are mentioned and their importance to the tire engineer is indicated.
Pattern and variability in the breeding system of Atlantic salmon (Salmo salar), with comparisons to other salmonids
Authors: Fleming Ian A
Published: April 2011

The breeding system of Atlantic salmon (Salmo salar) is shaped both by natural selection for offspring production and by sexual selection for access to mating opportunities. These evolutionary forces operate with differing intensities in the two sexes to shape their breeding behaviour and tactics. Female breeding success is largely dependent on egg production, access to breeding territories, and nest quality and survival. By contrast, male breeding success is largely determined by access to ovipositing females. As such, the breeding system of Atlantic salmon is similar to that of other members of the subfamily Salmoninae. However, early male maturity, a common pattern within the Salmoninae, reaches its greatest expression in both terms of frequency and magnitude of the mature male size difference in Atlantic salmon. Despite generalities, spawning populations of Atlantic salmon are not static, as they exhibit spatial and temporal variability in demography (e.g., spawner density, sex ratio, age at maturity, and body size). Events, both natural and anthropogenic (e.g., exploitation, habitat alteration, and climatic changes), affect this variability and ultimately shape the breeding system.
Multi-scale determinants of secondary production in Atlantic salmon (Salmo salar) streams
Authors: Poff N LeRoy , Huryn Alexander D
Published: April 2011

Understanding variation in the freshwater production of Atlantic salmon across its range is a critical aspect of the species' conservation, restoration, and management. We focus on how environmental factors operate at four hierarchical scales (region, watershed, reach, local habitat) to influence the production and survivorship of juvenile salmon and the production of their invertebrate food base. Using published, quantitative information about invertebrate production in small, cold streams characteristic of Altantic salmon nursery streams, we estimate expected maximum salmon production will be ca. 9 (range 6-22)g wet mass · m-2 · year -1, which compares favorably with reported literature values of < 1 to 17 g · m-2. We highlight some empirically based, shortcut approaches to estimating invertebrate production that may be particularly useful for evaluating salmonid production across a range of scales. We also consider how availability of invertebrate prey may influence salmon production. As a synthesis, we integrate existing information into a multi-scale framework by making qualitative predictions (hypotheses) about expected patterns of invertebrate and salmon production at different habitat scales. We then develop quantitative, heuristic scenarios that predict (hypothesize) how salmon and invertebrate production will change in response to selected physicochemical and non-trophic habitat limitations operating at the watershed (geology, land use) and reach (channel form, canopy) scales. Predicted values, which fall within the range of observed values for Atlantic salmon streams, demonstrate that a multi-scale habitat perspective can provide important insights into local to regional variation in the production of Atlantic salmon across its range and thus contribute to Atlantic salmon conservation, restoration, and management.
Proactive responses to human impacts that balance development and Atlantic salmon (Salmo salar) conservation: an integrative model
Authors: Wilzbach Margaret A , Mather Martha E , Folt Carol L , Moore Andrew , Naiman Robert J , Youngson Alan F , McMenemy James
Published: April 2011

Incorporating human impacts into conservation plans is critical to protect natural resources. Using a model that examines how anthropogenic changes might be proactively influenced to promote conservation, we argue that a denser human population does not spell inevitable doom for Atlantic salmon (Salmo salar). Humans affect the Atlantic salmon ecosystem deleteriously through landscape alteration, exploitation, external inputs, and resource competition. An intact ecosystem provides positive feedback to society by providing food, ecosystem services, and improving the quality of life. As Atlantic salmon and associated ecosystem benefits are increasingly valued by society, policies, laws, and regulations that protect salmon populations and habitats are codified into a "control system" or institutional infrastructure. Via research that helps maintain wild salmon populations and in informing the public about the benefits of a healthy Atlantic salmon ecosystem, scientists can influence public attitudes and facilitate the implementation of environmental policies that moderate harmful anthropogenic changes. Because exchange among scientists is of paramount importance in increasing our understanding of important interrelationships between humans and fish, we recommend the establishment of an international salmon organization for research.
The dynamothermal aureole of the Donqiao ophiolite (northern Tibet)
Authors: Zhou Mei-Fu , Malpas John , Robinson Paul T. , Reynolds Peter H.
Published: April 2011

Metamorphic rocks found at the base of the Jurassic Donqiao ophiolite of northern Tibet are interpreted as a basal dynamothermal aureole produced during obduction of the massif. The rocks form a sequence some 8 m thick, varying from high-grade amphibolites at the contact with overlying harzburgites to greenschist facies metasedimentary rocks lower down. The mineral paragenesis is similar to other such aureoles, and indicates that temperatures in excess of 750 °C may have been reached during metamorphism. The lack of high-pressure minerals suggests that the rocks were produced by subcretion in a relatively shallow dipping subduction zone. Ar–Ar geochronology on amphibole separates provides dates of 175–180 Ma for the displacement of the ophiolite, significantly older than the age of emplacement estimated from stratigraphie relationships. The ophiolite was clearly obducted very soon after its formation in a suprasubduction zone environment.
Interpretation of lithofacies of the Ashtabula Till along the south shore of Lake Erie, northeastern Ohio
Authors: Szabo John P. , Bruno Pierre W.
Published: April 2011

The final advance of the Erie lobe into Ohio during the Port Bruce Stade of the Late Wisconsinan deposited the Ashtabula Till. Wave erosion and mass wasting along the south shore of Lake Erie show that the Ashtabula Till consists of laterally traceable lithofacies, which are used to determine the depositional history of the Ashtabula Till. At each section, lithofacies sequences are divided into two sub-sequences, each consisting of massive, matrix-supported diamicton (Dmm) overlain by stratified, matrix-supported diamicton (Dms). Some Dmm are sheared (Dmm(s)) and are interpreted as lodgement till, whereas other Dmm and Dms were deposited as melt-out till. Some sections contain lenses of fines (Fm and Fl), current-reworked diamictons (Dmm(c) and Dms(c)), and resedimented diamictons (Dmm(r) and Dms(r)). The two sub-sequences represent two advances of Ashtabula ice that deposited the Euclid and Painesville moraines about a kilometre apart. During and after recession of the Ashtabula ice, waves and currents in Lake Maumee and its successors reworked outwash and diamictons to form the lake plain. The texture of Dmm(s) is significantly different from that of most other diamictons, and Dmm has the smallest carbonate content of all diamictons. Analysis of the variations in texture and composition among lithofacies provides additional evidence of the effectiveness of lithofacies logging in interpretation of glacial processes.
The Dirt Hills structure: an ice-thrust feature in southern Saskatchewan, Canada
Authors: Christiansen E. A. , Sauer E. Karl
Published: April 2011

The Dirt Hills structure is expressed at the surface as a broad, arcuate moraine, 7.5 km wide, 120 m high, and 40 km long. The structure is composed mainly of bedrock and drift consisting of three slabs stacked to form a single block 215 m thick. The shear zones that bound the slabs are mainly in clays of the Bearpaw Formation. The Dirt Hills structure originated during the last deglaciation when the glacier, under compressive flow, readvanced up the Missouri Coteau escarpment and stacked the subglacial slabs of bedrock and drift. The subparallel, arcuate ice-thrust ridges are formed presumably by imbricate thrust faults originating from the uppermost shear zone.
Lithostratigraphy and geochemistry of the Cottrells Cove Group, Buchans – Roberts Arm volcanic belt: new constraints for the paleotectonic setting of the Notre Dame Subzone, Newfoundland Appalachians
Authors: Dec Tomasz , Swinden H. Scott , Dunning R. Greg
Published: April 2011

New sedimentological, geochemical, and geochronological data from the Cottrells Cove Group in central Newfoundland provide important constraints on the nature of the Notre Dame Subzone, its tectonic setting, and the history of the Laurentian margin during the Early Ordovician. The Cottrells Cove Group forms the eastern extension of the Roberts Arm Group and correlates with the Chanceport Group on New World Island. It is represented by two volcano-sedimentary formations that occur in a complex thrust stack. The Fortune Harbour Formation consists of calc-alkalic, island-arc lavas, followed by a 1250 m thick succession of volcaniclastic deposits, radiolarian cherts, and calc-alkalic, mafic flows, which were deposited in a back-arc, basin-plain setting. The volcaniclastic deposits include felsic tuff, which has a U–Pb zircon age of 484 ± 2 Ma and an inheritance component of 2517 ± 26 Ma. These new U–Pb and Nd-isotope data suggest that the island-arc–back-arc volcanism and sedimentation in the Notre Dame Subzone developed in the vicinity of continental margin and approximately 10 Ma earlier than has previously been established. The Moores Cove Formation is undated but contains boulders of calc-alkalic basalt and is presumed to be at least in part younger than the Fortune Harbour Formation. Tholeiitic lavas, together with associated radiolarian cherts and volcaniclastic deposits, constitute the basal part of the Moores Cove Formation and may have been deposited in a back-arc environment synchronously with some parts of the Fortune Harbour Formation. They are conformably followed by an over 1200 m thick, coarsening-upward succession of lower-slope and submarine-fan deposits. The polymictic flysch, containing clasts of island-arc basalt, accompanied by other volcanic, plutonic, ultramafic, and sedimentary detritus, may record Middle or Upper Ordovician uplift and erosion of obducted arc–back-arc, volcano-sedimentary sequences and their ophiolitic substrate.
Gravity modelling along a Lithoprobe seismic traverse, northern Grenville Province, western Quebec
Authors: Telmat Hamid , Antonuk Caroline N. , Mareschal Jean-Claude
Published: April 2011

High-precision gravity data were collected along Lithoprobe seismic reflection lines in the northern part of the Grenville Province, in western Quebec. An interpretation is presented for line 52, which starts some 60 km southeast of the Grenville Front, traverses the parautochthonous Reservoir Dozois Terrane including the allochthonous slice of the Réservoir Cabonga Terrane, and ends near the town of Mont-Laurier, in the allochthonous Mont-Laurier Terrane. On the regional scale, the Bouguer gravity anomaly is consistent with the interpretation of the seismic reflection data. It supports crustal thinning southward of the Grenville Front, under the Cabonga allochthon. This thinning may be related to postorogenic extension. The gravity modelling shows dramatic thinning of the lower crust and suggests that extension was accommodated by extrusion of the lower crust. The gravity modelling also requires a steep boundary between the Réservoir Cabonga and the Réservoir Dozois terranes extending to ~ 15 km. The geometry of the Baskatong ramp derived from gravity data is also consistent with the seismic interpretation. This supports the suggestion that the Baskatong ramp is a major discontinuity along which Proterozoic terranes were accreted. In the Réservoir Cabonga Terrane in the northern part of the profile, the residual gravity anomalies (short wavelength variations) are related to outcropping mafic intrusions. Modelling of these anomalies complements the seismic reflection data, which did not image the base of the intrusions. The interpretation calls for three small distinct gabbroic bodies that extend no deeper than 3 km. The total volume of the intrusions is ~ 3000 km3.
Late Wisconsinan erosion and eolian deposition, Summer Island area, Pleistocene Mackenzie Delta, Northwest Territories: optical dating and implications for glacial chronology
Authors: Murton Julian B. , French Hugh M. , Lamothe Michel
Published: April 2011

The Summer Island area of the Pleistocene Mackenzie Delta, western Canadian Arctic, is thought to have been last glaciated during the Early Wisconsinan (>35 ka), with a suggested Late Wisconsinan (~13 ka) glacial limit located ~80–100 km to the south. Cryostratigraphic observations in the Summer Island area identify eolian and fluvial sediments overlying an erosion surface. On Summer Island, eolian sand occurs within sand wedges, the tops of which are contiguous with an eolian sand sheet deposited on a formerly bare ice surface. This paleo-ice surface is attributed to fluvial erosion, and that in turn is attributed to proglacial meltwater activity. The age of erosion is inferred to be shortly before ~14 ka, determined by optical dating (using infrared stimulation of luminescence from feldspar) of the eolian sand wedges. This ~14 ka meltwater erosion is significantly north of the generally accepted limit of Late Wisconsinan glaciation in this coastal area, suggesting that ice last covered the whole of Richards Island near the end of the Late Wisconsinan, rather than in the Early Wisconsinan, as previously thought.
U–Pb ages for magmatism and deformation in the New Quebec Orogen
Authors: Machado N. , Clark T. , David J. , Goulet N.
Published: April 2011

The New Quebec Orogen is a Paleoproterozoic fold and thrust belt, active from 2.17 to 1.77 Ga, bordering the eastern margin of the Archean Superior Province. The orogen developed on a long-lived, passive continental margin and comprises two volcanic – sedimentary sequences. The ages presented in this study help to bracket the magmatic and deformational history of the orogen. A glomeroporphyritic gabbro from the Hellancourt Formation was dated at 1874 ± 3 Ma and a rhyodacite from the upper Murdoch Formation yielded an identical age of 1870 ± 4 Ma. These data allow the correlation of the two units and indicate that they are 10–14 Ma younger than the estimated age for the Sokoman Formation. These ages, together with already published work, indicate that magmatism related to the younger magmatic event occurred at 1884–1870 Ma. Albitized pelites from the Murdoch Formation contain euhedral detrital zircons 2707–2690 Ma old, indicating that the source rocks were Archean. An undeformed monzonitic intrusion occurring close to Nachicapau Lake is 1813 ± 4 Ma old and is the lower limit for the age of deformation in the central sector of the orogen.
Holocene eolian activity in the Minot dune field, North Dakota
Authors: Muhs Daniel R. , Been Josh , Mahan Shannon A. , Burdett James , Skipp Gary , Rowland Zachary Muhs , Stafford Jr. Thomas W.
Published: April 2011

Stabilized eolian sand is common over much of the Great Plains region of the United States and Canada, including a subhumid area of ~1500 km2near Minot, North Dakota. Eolian landforms consist of sand sheets and northwest-trending parabolic dunes. Dunes and sand sheets in the Minot field are presently stabilized by a cover of prairie grasses or oak woodland. Stratigraphic studies and accelerator mass spectrometry radiocarbon dating of paleosols indicate at least two periods of eolian sand movement in the late Holocene. Pedologic data suggest that all of the dune field has experienced late Holocene dune activity, though not all parts of the dune field may have been active simultaneously. Similar immobile element (Ti, Zr, La, Ce) concentrations support the interpretation that eolian sands are derived from local glaciofluvial and glaciolacustrine sediments. However, glaciolacustrine and glaciofluvial source sediments have high Ca concentrations from carbonate minerals, whereas dune sands are depleted in Ca. Because noneolian-derived soils in the area are calcareous, these data indicate that the Minot dune field may have had extended periods of activity in the Holocene, such that eolian abrasion removed soft carbonate minerals. The southwest-facing parts of some presently stabilized dunes were active during the 1930s drought, but were revegetated during the wetter years of the 1940s. These observations indicate that severe droughts accompanied by high temperatures are the most likely cause of Holocene eolian activity.
Determining sampling date interval for precise in situ estimates of cumulative food consumption by fishes
Authors: Whitledge Gregory W , Hayward Robert S
Published: April 2011

We tested the influence of sampling date interval (SDI) on precision of in situ estimates of cumulative food consumption by fishes. Daily rations of stream-dwelling green sunfish (Lepomis cyanellus) and impoundment-dwelling bluegill (Lepomis macrochirus) were estimated for 30 consecutive days using a low-effort procedure. Cumulative consumption by each species over the 30-day period (and 95% CIs) was estimated using Monte Carlo simulations. The effect of SDI on cumulative consumption estimates was examined by calculating cumulative consumption for SDIs of 1, 2, 3, 4, 5, 6, 7, 10, 14, and 30 days; the 1-day SDI served as a standard for evaluation of other SDIs. Cumulative consumption estimates began to fall outside the 95% CI for the 1-day SDI at SDIs of 3-4 days and did so with with increasing frequency as SDI increased. Error in estimating cumulative consumption was almost always [Formula: see text]15% relative to the 1-day SDI standard at SDIs of 5 days or less but was as high as 26 and 39% at SDIs of 6 and 7 days, respectively. Our results suggest that sampling at least every 5 days may be required to obtain precise estimates of cumulative consumption by fishes in lotic systems and small impoundments.