bluuebunny/crossref_metadata_2025 huggingface dataset:
Mycobacterium bovisBCG Immunization Induces Protective Immunity against Nine DifferentMycobacterium tuberculosisStrains in Mice
Authors: Jeon Bo Young , Derrick Steven C. , Lim JaeHyun , Kolibab Kristopher , Dheenadhayalan Veerabadran , Yang Amy Li , Kreiswirth Barry , Morris Sheldon L.
Published: August 2008

Recent preclinical and epidemiologic studies have suggested that certainMycobacterium tuberculosisgenotypes (in particular, Beijing lineage strains) may be resistant toMycobacterium bovisBCG vaccine-induced antituberculosis protective immunity. To investigate the strain specificity of BCG-induced protective responses in a murine model of pulmonary tuberculosis, C57BL/6 mice were vaccinated with BCG vaccine and then challenged 2 months later with one of nineM. tuberculosisisolates. Four of these strains were from the W-Beijing lineage (HN878, N4, NHN5, and ChS) while four were non-Beijing-type isolates (C913, CDC1551, NY669, and NY920). As a control, the WHO standardM. tuberculosisErdman strain was evaluated in these vaccination/challenge experiments. To assess the protective responses evoked by BCG immunization, organ bacterial burdens and lung pathology were assessed in vaccinated and naïve mice at 4, 12, and 20 weeks postchallenge as well as during the day of infection. At 4 weeks after the aerosol challenge with each of these strains, significantly reduced bacterial growth in the lungs and spleens and significantly improved lung pathology were seen in all vaccinated animals compared to naïve controls. After 12 weeks, reduced organ bacterial burdens were detected in vaccinated animals infected with six of nine challenge strains. Although lung CFU values were lower in vaccinated mice for only three of nine groups at 20 weeks postchallenge, significantly decreased lung inflammation was seen in all immunized animals relative to controls at 20 weeks postchallenge. Taken together, these data demonstrate that BCG vaccination protects against infection with diverseM. tuberculosisstrains in the mouse model of pulmonary tuberculosis and suggest that strain-specific resistance to BCG-induced protective immunity may be uncommon.
Factors affecting at-rest lateral stress in artificially cemented sands
Authors: Zhu Fanyu , Clark Jack I. , Paulin Michael J.
Published: August 2008

This paper presents the results of a laboratory study on the at-rest lateral stress and Ko of two artificially cemented sands. A modified oedometer ring was used to measure the lateral stress of cemented and uncemented sands. Test materials were No. 3 Ottawa sand and a marine sand with Portland cement. The specimens were prepared using the method of undercompaction to minimize the influence of specimen preparation on test results. The cement contents were 0, 0.5, 1.0, 2.0, 4.0, and 8.0% by the weight of dry sand. The water content of the specimens was 4% of the weight of dry sand and cement. When the sands were cured under zero confining pressure, the test results indicated the following: the at-rest lateral stress in cemented sands decreases significantly with increasing cement content; the relationship between the vertical and at-rest lateral stress is nonlinear and the value of Ko increases with increasing vertical stress; and the lateral stress decreases with sand density and curing period. When the specimens were cured under vertical stress, the value of Ko during the removal of vertical loading increased with both overconsolidation ratio and cement content. Stress history has a significant influence on the behaviour of at-rest lateral stress in cement sands. Key words : cemented sand, Ko, lateral stress, overconsolidation, stress history.
Behaviour of pile foundations under special loading conditions: 1994 R.M. Hardy keynote address
Authors: Meyerhof G. G.
Published: August 2008

Previous analyses of the ultimate resistance and displacements of rigid piles under lateral loads and moments have been extended to the general case of eccentric and inclined loads on flexible piles by using the concept of effective embedment depths of equivalent rigid piles. Recent research on the behaviour of large model tests on instrumented rigid and flexible piles under eccentric and inclined loads in sand, clay, and layered soil is summarized. Reasonable agreement is found between observed and predicted behaviour. The proposed method of analysis is also supported by comparison with the results of many field case records of single piles and large pile groups under lateral loads indifferent types of soils. Key words : bearing capacity, displacement, eccentric loads, inclined loads, layered soil, pile.
Selection and application of a one-dimensional non-Darcy flow equation for two-dimensional flow through rockfill embankments
Authors: Hansen David , Garga Vinod K. , Townsend D. Ronald
Published: August 2008

Porous embankments comprised of relatively homogeneous coarse rockfill can be used to reduce the amount of spillage at downstream hydro dams or to control the outflow from stormwater detention basins. The stage-discharge rating curve is important in the design of such applications. In general, the coarseness of the material causes the flow to be non-Darcy; that is, characterized by a nonlinear relationship between bulk velocity and hydraulic gradient. Six one-dimensional (1D) non-Darcy flow equations, appearing in the literature, are presented. A limited comparison between computed and experimental results is then made on the basis of 1D packed-column tests performed in the hydraulics laboratory of the University of Ottawa. The question as to how such 1D closed-conduit equations might be used to estimate the quantity of flow through a porous embankment is then addressed, considering that the latter has a free surface and is a two-dimensional (2D) flow. The problem is successfully dealt with using the concept of "effective hydraulic gradient," a concept reminiscent of the method of sections used to analyze confined 2D seepage problems. A general equation is presented in which the effective hydraulic gradient is shown to be a function of two factors: (1) the shape of the embankment and (2) the upstream depth, relative to the height of the dam. The development and verification of the equation for the effective hydraulic gradient is described, together with its use in obtaining a rating curve for a hypothetical flowthrough dam composed of rock material 0.25 m in diameter. Key words : non-Darcy flow, flowthrough rockfill, effective hydraulic gradient, stage-discharge rating curve.
Embankment failures at Vernon, British Columbia
Authors: Crawford C.B. , Fannin R.J. , Kern C.B.
Published: August 2008

A section of Highway 97, west of Vernon, B.C., is located over a soft-to-firm, compressible, silty clay subsoil. In addition to an extensive site investigation, the performance of two test embankments was observed for 2 years before construction was begun on the highway grade between them. When the highway fill reached a maximum thickness of about 10 m a failure occurred. The design was then changed to include berms on either side, but a second failure occurred when the grade was rebuilt. An undrained back-analysis of the first failure shows the influence of various variables on the factor of safety and illustrates the difficulty of choosing appropriate strength values for design when the site has a strong crust overlying a weaker layer and there is potential for progressive failure. Observations of settlements, pore pressures, and lateral movements in the subsoil describe the performance of the embankment during construction and reveal the importance of strain softening as a factor in the failures. Comparisons with a variety of similar failures in Canada, Scandinavia, and southeast Asia provide some guidance for future construction over similar materials. Key words : case history, embankment failure, field observation, pore pressures, stability, strength, undrained analysis.
The use of upward gradients to arrest downward dense, nonaqueous phase liquid (DNAPL) migration in the presence of solubilizing surfactants
Authors: Longino Bettina L. , Kueper Bernard H.
Published: August 2008

This paper presents a mathematical analysis and the results of a series of laboratory experiments investigating in situ dissolution of dense, nonaqueous phase liquid (DNAPL) pools from porous media using solubilizing surfactants under upward-flowing conditions. Surfactant flood experiments were conducted in a one-dimensional glass column packed with natural sand. Perchloroethylene (PCE) was emplaced in the column as a pool perched above a coarse–fine sand interface to reproduce conditions occurring when DNAPL pools on a low permeability layer in the subsurface. Aqueous surfactant solution was directed vertically upward to counteract downward pool mobilization resulting from reduction of the PCE-water interfacial tension in the presence of surfactant. Experiments were conducted at overall hydraulic gradients across the sand pack of 0.0, 0.1, 0.2, 0.3, and 0.5. The surfactant flood solution consisted of a 1:1 blend of two commercial surfactants, Witconol NP-100 and Rexophos 25/97, in a 2% aqueous solution. Surfactant flooding was conducted until all visible traces of PCE were removed from the column. Subsequent water flooding was continued until effluent PCE concentrations exiting the column dropped below 5 ppm. In the zero gradient experiment, the PCE pool invaded the fine sand layer immediately upon contact with the surfactant because of a lowering of interfacial tension. PCE entry into the fine sand did not occur in the 0.3 and 0.5 gradient runs. Minor amounts of PCE mobilization occurred in the late stages of the 0.1 and 0.2 gradient runs and is attributed to a lowering of interfacial tension with time upon exposure to surfactant. Key words : solubilizing surfactant, groundwater remediation, DNAPL, tetrachloroethylene.
Interpretation of undrained creep tests in terms of effective stresses
Authors: Sheahan Thomas C.
Published: August 2008

The paper provides an effective stress-based interpretation technique for undrained creep behavior in cohesive soils. This technique could ultimately be used to predict whether a particular applied shear stress level will lead to failure or creep rupture. During the primary phase of undrained creep at constant shear stress, the soil's strain rate decreases, which in turn leads to a decrease in the undrained shear strength. However, it has been shown for a number of soils that a minimum undrained strength, or upper yield strength (suy), is eventually reached regardless of further strain rate decreases. It has been postulated that this phenomenon is part of a time-dependent behavior framework in which the yield locus shrinks with decreasing strain rate until some limiting surface, the static yield surface (SYS), is reached. Such a surface has been the basis for a number of constitutive models in which it represents the inviscid, or rate independent, behavior. The peak shear stress on the SYS corresponds to suy. Data from previous experimental programs are presented to show the existence of the surface and its role in undrained creep behavior. Undrained creep shear stress levels above suylead to creep rupture on the failure envelope; stress levels below suycause creep to the SYS, where the stress state apparently stabilizes without failure. The value of suycan be used in a number of analyses in creep susceptible soils, and the static yield condition can be used in the field to determine whether measured pore pressures are exceeding predicted nonrupture levels. A method is proposed for simple determination of the SYS using constant strain rate undrained shear tests. Key words : clays, consolidated-undrained tests, creep, rate effects, rheology, shear strength.
Frost protection of buried PVC water mains in western Canada: Discussion
Authors: Horvath John S.
Published: August 2008

not available
THE EFFECT OF INSECTICIDES ON THE RATE OF OXYGEN CONSUMPTION IN BLATTELLA
Authors: Harvey G. T. , Brown A. W. A.
Published: August 2008

The effect of 26 insecticidal compounds upon the rate of oxygen consumption of the German cockroach was ascertained by their injection into adult male insects at the approximate LD50 level. The chlorinated hydrocarbons, dinitro compounds, pyrethrins, nicotine, azobenzene, and the organic phosphates had a pronounced stimulatory effect upon this rate. With the chlordane compounds, also aldrin and dieldrin, this effect was preceded by a long latent period. Ryania and rotenone were depressant after a slight initial raising of the rate of respiration, while sabadilla gave a slight rise but was not depressant. Phenothiazine had little or no effect; and the organic thiocyanates were entirely depressant. Similar results were obtained by spray application of these insecticides.
SOME OBSERVATIONS OF THE NUMBER OF BLACK FLIES (DIPTERA, SIMULIIDAE) LANDING ON COLORED CLOTHS
Authors: Davies D. M.
Published: August 2008

The number of black flies alighting on cloths of different colors, each tested with a control of black cloth, varied with the intensity of the light reflected from the cloth and to a lesser extent with the wavelength. Dark blue was the color most frequented followed by dark brown, black, dark green, dark red, medium gray, and white.
AN ANNOTATED LIST OF THE LEPIDOPTERA OF ALBERTA
Authors: Bowman Kenneth
Published: August 2008

This list consists of 1825 species and varieties of Lepidoptera which have been taken in Alberta. Of these, 657 are records of captures in the hitherto almost completely neglected Microlepidoptera. Though few specialists on this continent have studied the taxonomy of this large group, those who have done so in certain families have generously assisted in classifying the species which are recorded. Unfortunately, in a few families it has been impossible to obtain this assistance. Despite the omissions this necessitates, the list constitutes the most comprehensive catalogue of Microlepidoptera which has, up to the present, been attempted for any province in the Dominion.Arrangement and nomenclature are based on McDunnough's Check List of the Lepidoptera of Canada and the United States, published in 1938 and 1939. Proposed modifications in nomenclature, presented in subsequent publications, are substituted if they appear to be gaining general acceptance.Locality records for captures are presented by a system of ecological areas of which the chief climatological and biological characteristics are briefly described.
COSMOCEPHALUS FIRLOTTEI N. SP. (FAMILY ACUARIIDAE) FROM THE SEA GULL (LARUS ARGENTATUS)
Authors: Rao N. S. Krishna
Published: August 2008

Cosmocephalus firlottei n. sp. (Family Acuariidae, subfamily Acuariinae) is described from the sea gull, Larus argentatus.
CALORIMETRIC DETERMINATION OF AVERAGE BODY TEMPERATURE OF SMALL MAMMALS AND ITS VARIATION WITH ENVIRONMENTAL CONDITIONS
Authors: Hart J. S.
Published: August 2008

A method is described for determining average body temperature of mice by placing them immediately after killing in a Dewar flask containing water and recording the temperature rise. Evidence is presented to show that postmortem heat production does not contribute appreciably to the results. Average body temperatures are usually about 2 °C. lower than colonic temperatures except during lethal chilling when average temperatures are frequently higher than colonic. The rise in average body temperature produced by activity increases with environmental temperature. Body temperatures may be lower during activity than during rest at cold air temperatures.
P32-INDUCED LETHAL MUTATIONS IN DROSOPHILA
Authors: Arnason T. J. , Irwin R. L. , Spinks J. W. T.
Published: August 2008

X-chromosomes of P32-treated wild-type Drosophila melanogaster were tested for the presence of recessive lethal mutations. Treated larvae were reared in food medium containing initially 6.5, 32.5, 65.0, or 162.5 mrd. P32 per ml. Of 838 tested chromosomes 42 had recessive lethals. The frequency of mutation was roughly proportional to P32 content of the food. An initial concentration of 18.8 mrd. P32 in larval food is expected to produce about the same frequency of recessive lethal mutations as is obtained with 1000 r. of X rays applied to mature sperm. A fly reared in medium having an initial concentration of 32.5 mrd. per ml. receives, prior to mating, a calculated total radiation dose of 0.62 gram roentgens. At this dosage 4.2% recessive lethals were recorded. For equivalent amounts of ionization P32 is here apparently 2.3 times as effective as X rays.
SOME ASPECTS OF MOISTURE ABSORPTION AND LOSS IN EGGS OF MELANOPLUS BIVITTATUS (SAY)
Authors: Salt R. W.
Published: August 2008

The penetration of moisture into or out of eggs of Melanoplus bivittatus (Say) is assisted or retarded by a variety of envelopes. Proceeding inwardly these are, in the newly laid egg, the chorion, the primary lipoid layer (probably waxy), and the vitelline membrane; later, to these are added the secondary lipoid layer (probably oily), the yellow cuticle, a bonding material, the white cuticle, and the serosa, which secretes all the others of this group. The primary lipoid layer waterproofs the egg in its earliest stages, but its function is soon taken over by the secondary lipoid layer. A specialized moisture-permeable area, the hydropyle, is formed at the posterior pole. Moisture is absorbed from the environment chiefly through the hydropyle, reaching a peak of absorption on the eighth or ninth day at 25 °C. and then decreasing because of the limited expansion of the cuticular layers. The original moisture content of the egg is approximately doubled. Moisture loss in young eggs, up to seven days of age, is restricted at first by the primary lipoid layer and later by the secondary lipoid layer. From the eighth day to the end of anatrepsis, on the 14th day, the desiccation rate is greatly increased. Most of the loss occurs through the hydropyle, which at this time is normally absorbing water; however, the relationship between loss and gain through the hydropyle is not close. After blastokinesis, or after the 14th day of incubation at 25 °C., the desiccation rate is extremely variable. Some of the moisture loss takes place through the hydropyle, and when the rate is low all of it does so; however, in many eggs the general cuticular surface becomes permeable (to desiccation but not to absorption), and the losses are erratic and unpredictable. With the gradual onset of diapause after the 21st day, the desiccation rate declines. Changing the moisture conditions during incubation of the eggs results in changes in the desiccation rates. The variability of the rates in older eggs was not caused by retardation of development, irregular moisture absorption, intermittent drying, or laboratory techniques, but was probably the result of variable cuticular permeability. Most M. bivittatus eggs, regardless of age, survived losses up to one-third of their moisture content, but few survived more than a two-thirds loss. After more than a one-third loss, the collapsing action of the egg frequently produced distorted or abnormal embryos. Though these often lived for some time, they never hatched. Those individuals and those age groups with the lowest desiccation rates naturally survived dry conditions longest.
AIR-MASS CLIMATOLOGY OF ONTARIO NORTH OF LAKE HURON AND LAKE SUPERIOR BEFORE OUTBREAKS OF THE SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (CLEM.), AND THE FOREST TENT CATERPILLAR, MALACOSOMA DISSTRIA HBN. (LEPIDOPTERA: TORTRICIDAE; LASIOCAMPIDAE)
Authors: Wellington W. G.
Published: August 2008

Previous work showed that ideal physical conditions for the development of the spruce budworm, Choristoneura fumiferana (Clem.), occur when the weather is relatively dry and clear. These conditions have tended to occur in summers when the annual number of cyclonic centers passing over the area was declining, and have preceded past outbreaks. On the other hand, the physical requirements of the forest tent caterpillar, Malacosoma disstria Hbn., include warm, humid, cloudy weather during much of the larval stage, and outbreaks of this species in Ontario have begun after an increase in the annual number of cyclonic passages. While the annual number of cyclonic passages is declining in periods before spruce budworm outbreaks in northern Ontario, the number of these passages in the summer months falls below average. Furthermore, the majority of the centers that do pass in these months contain air masses of polar continental or maritime origin. The more humid southwestern air masses are usually barred from the area by a southward shift of the whole circulation pattern. This situation is reversed in periods before M. disstria outbreaks. While the annual number of passages is increasing, the number occurring in the summer months is above average, as is the proportion of southwestern air masses occurring in these months. Northern and western air masses are usually active farther north, owing to a northward shift of the whole circulation pattern.
VASCULARITY OF THE HYPOPHYSIS OF LOWER VERTEBRATES: THE PAINTED TURTLE,CHRYSEMYS PICTA MARGINATAAGASSIZ
Authors: Taylor Stanley James
Published: August 2008

Measurements were made on the diameter and length of the capillaries of the turtle hypophysis. The volume and surface of vessels were calculated and compared with those of the cat, frog, and salamander. Only the anterior lobe showed vessels which were significantly wider than in the adjacent brain tissue. The surface area of blood in the anterior and tuberal lobes is very extensive, 17 sq. mm. to 18 sq. mm. for 1 cu. mm. of fresh tissue, and is between two and three times as great as in the other lobes and in the richest centers of the brain. The vascular surface in each lobe, except the intermediate one, is lower than, but shows similar variation to, that of the cat. The pars nervosa is supplied by vessels between it and the pars intermedia as in the salamander and is unlike that of the frog or cat with numerous vessels penetrating its substance.
A STUDY OF SIZE INHERITANCE IN THE HOUSE MOUSE: II. ANALYSIS OF FIVE PRELIMINARY CROSSES
Authors: Butler L.
Published: August 2008

Five crosses were made between mice of different body size, and over 2000 mice were raised in the F1, F2, and backcross generations. The body weight at 60 days after birth was used as the criterion of size. The male means were always larger than the corresponding female means and the difference in weight between the two sexes increased progressively with body size. Litter size and sequence had no effect on body size. The adequacy of the gram scale was tested with inconclusive results which indicated that in at least two crosses some other scale should be used. Log-grams were substituted for grams and gave a good fit in cross No. 3 but not in crosses Nos. 1 and 2. The evidence from selection experiments, environmental variability, and sex differences in size indicate that on a gram scale at least part of the factors which affect body size are proportionate rather than additive in nature. In all five crosses the F1and F2means are intermediate between the parents. The backcross means are halfway between the F1and the respective parent. Only one cross showed increased size in the F1which might be interpreted as due to heterosis. Reciprocal crosses gave significantly different results and the dissimilarity was carried over into the next generation. This difference was attributed to the environmental effects of female body size. As expected, the variances of the P1's and the F1were similar but, contrary to expectation, the F2variance was no larger than that of the F1. Litter size showed a different type of inheritance. One cross between P1's with mean litter sizes of 5.1 and 10.2 gave an F1mean of 13.2 young. This was tentatively interpreted as dominance of large litter size and hybrid vigor allowing more embryoes to reach parturition.
OCCURRENCE OF AMINO ACIDS IN THE HONEYDEW OF THE CRESCENT-MARKED LILY APHID, MYZUS CIRCUMFLEXUS (BUCK.)
Authors: Maltais J. B. , Auclair Jacques L.
Published: August 2008

The honeydew of Myzus circumflexus feeding on Katahdin potato contains 22 free amino acids and amides, which are given in their respective amounts. Carbohydrates constitute also an important portion of this product of digestion in aphids. Analyses of amino compounds in honeydew may be of prime importance in the study of the causes of plant resistance to aphids.
SOME EFFECTS OF PROGESTERONE ON THE RESPONSE OF THE IMMATURE PULLET TO ESTROGEN, AND SOME OBSERVATIONS ON THE EFFECTS OF GONADAL HORMONES ON THE AVIAN SPLEEN AND KIDNEY
Authors: Phillips W. E. J. , Common R. H. , Maw W. A.
Published: August 2008

Progesterone depressed the hypertrophy of the immature pullet's oviduct evoked by estrogen, but did not significantly affect the responses of liver weight, total liver crude protein, and serum calcium level evoked by estrogen. These effects are in some respects the converse of previously recorded effects of thiour-acil on the response of the pullet to estrogen. Progesterone did not affect the increases of liver pentose nucleic acid and desoxypentose nucleic acid evoked by estrogen. Testosterone propionate by itself, at the levels used, did not affect the amounts or ratios of liver pentose nucleic acid and desoxypentose nucleic acid. Estrogen reduced spleen weight to a highly significant degree, and progesterone significantly reduced this effect of estrogen. Testosterone did not affect spleen weight. In the experiment described estrogen increased kidney weight to a highly significant degree; progesterone tended to reduce this effect, but the tendency did not attain significance at P = 0.05.
FACTORS INFLUENCING THE PERFORMANCE OF THE PRECIPITIN TEST IN THE DETERMINATION OF BLOOD MEALS OF INSECTS
Authors: Eligh G. S.
Published: August 2008

Certain factors influence the performance of precipitin tests when the latter are used for detection of blood meals of biting flies. Antisera stored in a liquid state in a refrigerator generally show a decrease in titer with the passage of time. Aging appears to have an adverse effect on the avidity of an antiserum. Smears of blood-engorged mosquitoes prepared by smearing of the entire insect are satisfactory for testing by the precipitin reaction. A high-titered antiserum which can be diluted is desirable for detection of host blood in mosquitoes.
THE POPULATION AND ACTIVITY OF ADULT FEMALE BLACK FLIES IN THE VICINITY OF A STREAM IN ALGONQUIN PARK, ONTARIO
Authors: Davies Douglas M.
Published: August 2008

The population of females of Simulium venustum Say on the wing was measured by hand-netting. The population varied annually and seasonally coincident with the number and longevity of immigrant and emergent flies. Longevity in turn was probably related to the rainfall.Activity was divided into flying, attraction, landing, and biting, the first two measured by hand-netting and the last two by counts on a unit area of human skin in the shade. Flying usually varied diurnally, a large peak in the evening and a small one in the morning. Attraction varied with none of the meteorological factors measured. Biting and flying increased and landing decreased with rapidly changing, especially falling, pressure. Other factors influenced flying and landing, but not biting, when the area was in the shade. Flying was greatest between 60–80° F., at low but not zero saturation deficiencies, in light winds, and in zero to low rates of evaporation. Landing on the host was least below 55 °F. and at 65–75 °F., at zero and intermediate saturation deficiencies, and at moderately high rates of evaporation. These factors affected the flies landing on the host directly, and indirectly by curtailing the flying that brought flies to the host in the first place. In the direct sunlight landing decreased to one-half and biting; to one-quarter of that in the shade.
EFFECTS OF CERTAIN FUMIGANTS ON HAEMOCYTES OF THE MEDITERRANEAN FLOUR MOTH, EPHESTIA KÜHNIELLA ZELL. (LEPIDOPTERA: PYRALIDIDAE)
Authors: Arnold J. W.
Published: August 2008

A study was made of the effects of three fumigants, dichloroethyl ether, carbon tetrachloride, and methyl bromide, on the haemocytes of the Mediterranean flour moth. Cytological changes, total cell numbers, and the relative numbers of cells of each class were noted at intervals during fumigation and in recovering and moribund larvae after treatment. With each compound, fumigation caused passive–active cell changes and pathological conditions leading to cell degeneration and also resulted in significant decreases in cell numbers. Total cell numbers decreased further in individuals that failed to recover from fumigation. Recovery was associated with regenerative changes that resulted in increased cell numbers. The spheroidocytes were the principal cells involved in the increases and they were loaded with globules of neutral fats at that time. It is suggested that the spheroidocytes are associated with recovery, possibly through an ability to aid in the creation of fat reserves for energy metabolism under unfavorable conditions.
THE NONMUTAGENIC ACTION OF p-p′-DDT AND γ-HEXACHLOROCYCLOHEXANE IN DROSOPHILA MELANOGASTER MEIG. (DIPTERA: DROSOPHILIDAE)
Authors: Pielou D. P.
Published: August 2008

As experiments are in progress on selective breeding for insecticide tolerance in insect parasites and as various physiologically potent chemicals have been shown to cause mutation in Drosophila melanogaster Meig., tests were made to determine whether p-p′-DDT and γ-hexachlorocyclohexane had any mutagenic action. Wild type males of D. melanogaster that had been exposed to the former insecticide in their larval feeding medium, or, as adults, to the vapor of the latter insecticide, were tested. The Muller-5 method of detecting recessive lethal mutations in the X chromosome was used. No evidence of mutagenic action was found in either insecticidal isomer.
SOME EFFECTS OF TEMPERATURE ON THE EMBRYONIC DEVELOPMENT OF THE SALMON (SALMO SALAR)
Authors: Hayes F. R. , Pelluet D. , Gorham Eville
Published: August 2008

This is a study of the effects of temperature on morphogenesis, and is an attempt to determine whether the order of appearance of anatomical features can be altered within the limits of survival. The time in days (usually from closure of the blastopore) for features to appear was noted, and from this the rates were calculated, being the reciprocals of days × 103. Rate plotted against temperature gives in general a straight line whose slope may be calculated. Some slopes were: hatching, 4.6; digestive system, 6.4; skeleton, 6.5; nervous function, 8.2; external pigment, 9.6; blood vessels, 10.0; fins, 10.3; eye pigment, 12.5. Thus hatching would be expected to appear precociously at low temperatures, and eye pigment at high temperatures.
SEX DIFFERENTIATION IN THE PACIFIC SALMON ONCORHYNCHUS KETA (WALBAUM)
Authors: Robertson J. G.
Published: August 2008

The differentiation of the gonad is described in chum salmon embryos and alevins. Contrary to classical findings in teleosts, sex differentiation in the chum salmon proceeds in the male or female direction without an intermediate female phase. From an initially indifferent gonad there is a progressive development of one sex or the other. The organ forms as a fold from the splanchnic mesoderm and, at the time of first appearance, contains primordial germ cells. These enlarge to form the definitive germ cells which, after a series of divisions, form smaller oogonia or spermatogonia. Oogonia are followed by primary and secondary (growing) oocytes, the appearance of which is the criterion of sex distinction. Spermatogonia continue to multiply but do not undergo growth in the alevin. The ovary develops an open endovarial canal and is supported by a prominent mesovarium. The testis remains small and, in the alevin, develops no ducts. It is suspended by a mesorchium.
SURVIVAL OF MACROCENTRUS ANCYLIVORUS ROH., A PARASITE OF THE ORIENTAL FRUIT MOTH, ON DIFFERENT CONCENTRATIONS OF VARIOUS SUGAR SOLUTIONS
Authors: Pielou D. P. , Glasser R. F.
Published: August 2008

Newly emerged adults of the hymenopterous parasite Macrocentrus ancylivorus Roh. were fed for their entire adult lifetime on a diet consisting solely of a solution, of one sugar only, of specified concentration. Sexes were kept distinct. Temperature was constant at 26.5 °C. throughout the experiments. Dextrose, levulose, galactose, maltose, sucrose, and lactose were tested at seven concentrations ranging from 0.1% to 40%. The mean length of life on lactose at any concentration was only slightly longer than on water. Survival on galactose was moderate. Survival was satisfactory on all the remaining four sugars. The mean length of life on these sugars increased rapidly as concentration was increased and was optimal at 5%. Above this concentration survival declined, especially at high concentrations of 20% and 40%; however, at the latter concentrations survival was greater than at concentrations of 2.5%. Survival on a 10% honey solution was not as great as on solutions of the four sugars at the same concentration. The mean length of life of males generally was slightly less than that of females.
THE LIMNOLOGY OF AMETHYST LAKE, A HIGH ALPINE TYPE NEAR JASPER, ALBERTA
Authors: Rawson D. S.
Published: August 2008

Amethyst, at an altitude of 1965 m. (6450 ft.), is one of the few lakes in the Canadian Rockies investigated limnologically. The annual ice cover persists for nearly eight months, and the highest mean lake temperature is about 10° C. The water is clear, low in mineral content, and well oxygenated. Plankton and bottom organisms are of few species and present in quantities within the lowest range for oligotrophic lakes. The lake appears to be typically alpine oligotrophic, of a group characterized by some European workers as panoligotrophic. The only fish present is the rainbow trout, introduced in 1931. They grew rapidly, then deteriorated, and later made a slow recovery. The third generation has lost some of the characteristics of the parent stock Salmo gairdnerii kamloops, and begins to resemble the high mountain subspecies S.g. whitehousei.
COMPARATIVE TRANSMISSION OF POTATO VIRUS Y BY FOUR APHID SPECIES THAT INFEST POTATO
Authors: Bradley R. H. E. , Rideout D. W.
Published: August 2008

Single aphids of four species were observed with a hand-lens until each had touched its proboscis once on a tobacco plant infected with potato virus Y and then once on a healthy tobacco plant. The time that the proboscis remained touching the plants in each case was recorded. This procedure required only a few minutes for each aphid, and sometimes it was completed in less than a minute. During this process, the successful transmissions of potato virus Y by single aphids of Myzus persicae (Sulz.), Aphis abbreviata Patch, Macrosiphum solanifolii (Ashm), and Myzus solani (Kltb.) were 55, 31, 9, and 4% respectively. Vector efficiency was not due to difference in feeding behavior of these species. When single infective aphids were transferred to a series of five plants at five-minute intervals, M. persicae caused more infections and remained infective longer than A. abbreviata.
STUDIES ON DIPTEROUS PARASITES OF THE SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (CLEM.) (LEPIDOPTERA: TORTRICIDAE): II. PHRYXE PECOSENSIS (TNS.) (DIPTERA: TACHINIDAE)
Authors: Maw M. G. , Coppel H. C.
Published: August 2008

Phryxe pecosensis (Tns.) is a native parasite attacking several species of lepidopterous larvae. It has been reared consistently from collections of the spruce budworm made in British Columbia. The time required from egg deposition to the beginning of the formation of the puparium was 7 to 11 days, the female taking the longer period. The puparium was usually completed within a 24-hr. period and the adult emerged 9 to 11 days later. The life history and habits of the insect are described and the salient characters of the immature stages and the internal reproductive systems of the adults are illustrated and described.
THE EFFECTS OF SOME HORMONES AND RELATED COMPOUNDS ON THE BACTERIA-FREE CULTURE OF ENTAMOEBA INVADENS AND FREE-LIVING AMOEBAE
Authors: Lesser Elliott
Published: August 2008

Some 3-keto-Δ4 steroids and diethylstilboestrol significantly inhibited the growth of Entamoeba invadens in a bacteria-free medium containing fresh liver. The inhibitory action of the steroids is not as great in the presence of fresh liver as in the presence of bacteria. The possible relationship between the degree of inhibition and steroid structural formulae is considered. No compound tested affected the growth of Acanthamoeba castellanii or Hartmanella rhysoides.
STUDIES OF THE MECHANISM OF TRANSMISSION OF POTATO VIRUS Y BY THE GREEN PEACH APHID, MYZUS PERSICAE (SULZ.) (HOMOPTERA: APHIDAE)
Authors: Bradley R. H. E.
Published: August 2008

Wingless adults of Myzus persicae (Sulz.) usually ceased to be infective within minutes and always within hours after leaving tobacco infected with potato virus Y, the time being longer when the aphids were kept from feeding than when they fed, and aphids that were kept from feeding remained infective longer at 2 °C. than at 35 °C. After one to four hours without food, over 80% of M. persicae made initial feeding punctures that lasted less than a minute, and about 70% of these aphids transmitted potato virus Y after one such feeding puncture on an infected plant. Though virus was acquired by aphids during feeding punctures as brief as five seconds, those that made feeding punctures lasting 11–60 sec. were the most likely to become infective. The percentage of aphids that transmitted potato virus Y decreased when the stylets were inserted into infected plants for over a minute, and none of the aphids transmitted the virus after the stylets had been inserted over 20 min. The highest percentage of aphids transmitted potato virus Y when they were transferred to test plants immediately after a single brief feeding puncture on an infected plant. The percentage of aphids that transmitted the virus decreased when they spent 10 min. or longer on infected plants; also, the probability of their becoming infective during a single feeding puncture decreased by about one third during the first 10 min. they fed after one to four hours without food. Even when conditions were suitable, about 25% of M. persicae failed to transmit potato virus Y. Yet those that failed to transmit the virus in one infection trial transmitted it as readily in a second trial as those that transmitted it in the first.
A NUCLEAR AND A CYTOPLASMIC POLYHEDRAL VIRUS DISEASE OF THE SPRUCE BUDWORM
Authors: Bird F. T. , Whalen Mary M.
Published: August 2008

The spruce budworm, Choristoneura fumiferana (Clem.), is susceptible to two polyhedral virus diseases. The first, previously described, is characterized by the formation of polyhedra within the nuclei of tracheal matrix, fat, hypodermal, and blood cells. The polyhedra contain mostly rod-shaped particles 260 × 28 millimicrons. The second is a new type and is characterized by the formation of polyhedra in the cytoplasm of mid-gut cells. The polyhedra contain only spherical particles from 28 to 80 mμ in diameter. Both diseases occurred in the same insect but it was possible to separate the cytoplasmic disease from the nuclear disease by extracting groups of the cytoplasmic polyhedra from the mid-gut with a micromanipulator before the nuclear disease developed.
THE EFFECTS OF THE CARCINOGEN, 2-ACETYLAMINOFLUORENE, ON LARVAL AND ADULT FROGS
Authors: McCallion David J.
Published: August 2008

2-Acetylaminofluorene is a powerful carcinogen capable of inducing a variety of benign and malignant neoplasms in several species of animals and is required only in very small amounts for relatively short periods of time. It is somewhat soluble (1.3 mgm. per 100 cc.) in water. Frog tadpoles were raised in solutions of various strengths. Even dilute solutions proved to be highly toxic to these animals. In those animals that survived it was found that 2-acetylaminofluorene inhibits both total body growth and rate of tail regeneration; that the tadpoles remained dark (melanophores dilated) even on a light background; that lesions of the liver developed resembling those described in mammals resulting from treatment with the same and other carcinogens. It is not certain that these lesions are neoplastic, but they may be of the type that precede or accompany liver cell carcinoma. This carcinogen was also fed to or injected into adult frogs. Even small amounts were toxic to them and only a small number survived for more than a few days. In the survivors, after six to eight weeks, lesions of the liver, including necrosis and cirrhosis, appeared. No distinct neoplasms were produced.
STUDIES ON DIPTEROUS PARASITES OF THE SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (CLEM.) (LEPIDOPTERA: TORTRICIDAE): IV. MADREMYIA SAUNDERSII (WILL.) (DIPTERA: TACHINIDAE)
Authors: Coppel H. C. , Maw M. G.
Published: August 2008

Studies initiated in British Columbia in 1943 showed that Madremyia saundersii (Will.), a native parasite with a wide range of lepidopterous hosts in North America, was a parasite of the spruce bud worm, Choristoneura fumiferana (Clem.). The parasite has been obtained each year since then in moderate numbers and released in infested areas of Eastern Canada. M. saundersii deposits macrotype eggs on the integument of host larvae. The first stage larvae penetrate the integument of the host. The larvae attach themselves to tracheal trunks, where they remain throughout the first and second stages, but during the third feeding stage they wander freely within the body, devouring all the contents. The period from egg deposition to adult emergence was 17 to 23 days under laboratory conditions. The life history and habits of the insect are outlined, and are supplemented by general field observations. The immature stages of the parasite are illustrated and described.
NUTRITIONAL STUDIES WITHPSEUDOSARCOPHAGA AFFINIS(FALL.), A DIPTEROUS PARASITE OF THE SPRUCE BUD-WORM,CHORISTONEURA FUMIFERANA(CLEM.): I. A CHEMICALLY DEFINED MEDIUM AND ASEPTIC-CULTURE TECHNIQUE
Authors: House H. L.
Published: August 2008

A chemically defined medium consisting mainly of amino acids, dextrose, salts, and vitamins, and an aseptic technique are described for nutritional studies with larvae of Pseudosarcophaga affinis (Fall.), a dipterous parasite of the spruce budworm, Choristoneura fumiferana (Clem.) In feeding tests with 542 larvae, microorganisms contaminated only 3.9% of the initial number. Within an assay period of 20 days, 83.9% of the aseptic larvae reared on the medium reached the third instar. After removal from the rearing medium, 59.9% of the aseptic larvae pupated and a number of adults emerged. The time required for 50% of the aseptic larvae to develop to the third instar was 9.2 days. This is the first medium composed of chemically pure substances, with the exception of agar, to be successfully used for rearing a parasitic, entomophagous insect. Since the intervention of microorganisms can be avoided, a basis is provided for further nutritional studies with P. affinis.
THE INFLUENCE OF CARBON DIOXIDE ON THE UTILIZATION OF OXYGEN BY SOME FRESH-WATER FISH
Authors: Black Edgar C. , Fry F. E. J. , Black Virginia S.
Published: August 2008

The influence of carbon dioxide on the utilization of oxygen by 16 species of fresh-water fish from Algonquin Park, Ontario, Canada, has been measured by sealing fish individually in bottles containing water adequate in oxygen and with various concentrations of carbon dioxide. At death the ambient respired water was analyzed for free carbon dioxide and oxygen. Results give specific curves, which show that the oxygen in the respired water at the time of death was higher when the tension of carbon dioxide was increased. When the tension of carbon dioxide was low, the oxygen left in the water ranged from a tension of 4 mm. Hg for the northern brown bullhead, Ameiurus nebulosus, to 19 mm. Hg for the common brook trout, Salvelinus fontinalis. Carbon dioxide tensions causing death when a tension of 160 mm. Hg of oxygen remained in the respired water ranged from 80 mm. Hg for the northern blacknose shiner, Notropis heterolepis heterolepis, to 338 mm. Hg for the northern brown bullhead.
THE LIFE HISTORY OF THE NEMATODE METABRONEMA SALVELINI (FUJITA, 1920) PARASITIC IN THE SPECKLED TROUT, SALVELINUS FONTINALIS (MITCHILL), IN QUEBEC
Authors: Choquette L. P. E.
Published: August 2008

In Quebec, the first larval stages of the spirurid, Metabronema salvelini (Fujita, 1920), parasitic in the speckled trout, Salvelinus fonlinalis (Mitchill), are to be found in nymphs of the mayfly, Hexagenia recurvata, and in those of a species of the genus Polymitarcys. The fourth larval stage develops in the fish host. The third and fourth larval stages are described. The feeding of larvae-harboring nymphs of Hexagenia recurvata to trout resulted in the establishment of infection and development of adult worms in from 60 to 70 days.
A REVISION OF THE NEARCTIC CTENISCINI (HYMENOPTERA: ICHNEUMONIDAE): I. EUDIABORUS KERRICH AND A NEW GENUS
Authors: Mason W. R. M.
Published: August 2008

A key to distinguish the seven Nearctic genera of the tribe Cteniscini (Hymenoptera: Ichnenmonidae) is presented. The genus Eudiaborus Kerrich is discussed in detail with descriptions of, and a key to, 14 Nearctic species. Nine new specific, and three new subspecific, names are proposed. One species, formerly known only in the Old World, is reported from North America. A new genus and its two new species are described.
AGGRESSIVE BEHAVIOR OF UNDERYEARLING KAMLOOPS TROUT
Authors: Stringer G. E. , Hoar W. S.
Published: August 2008

The aggressive behavior of juvenile Kamloops trout (Salmo gairdneri kamloops Jordan) consists of chasing, nipping, retreating, threatening, and fighting. These different components are described. Territorial defence appears to be the end result of this behavior. Aggressiveness disappears at low light intensity when the fish settle to the bottom and remain quiet. A seasonal decline in aggressive behavior seems to occur during the spring. The sign stimulus releasing attack is a moving fish-shaped object approximately the same size as the trout. Dark colors have a stronger releasing value than bright colors. Fins and color patterns do not seem to be involved in the sign stimulus.
CYTOLOGY AND PARTHENOGENESIS OF THE WHEAT STEM SAWFLY, CEPHUS CINCTUS NORT. (HYMENOPTERA: CEPHIDAE)
Authors: Mackay Margaret Rowlatt
Published: August 2008

A chromosome complement of 18 was established for the female of Cephus cinctus Nort. by counts of 18 elements at oogonial metaphase and nine bivalents at pachytene. The male has a haploid set of nine chromosomes on the basis of counts at spermatogonial metaphase and at meiotic metaphases I and II. Male haploidy was confirmed by the fact that the male karyotype comprises one member of each morphologically identifiable pair present in the female. Spermatogenesis is characterized by lack of synapsis and complete abortion of the first meiotic division. Formation of a monopolar spindle at first meiotic metaphase is discussed. A cytological comparison of thelyotokous and arrhenotokous strains of C. cinctus failed to reveal any difference in chromosome number or in chromosome morphology. Cephus cinctus reproduces largely by arrhenotoky, the population normally being bisexual; the males develop from unfertilized eggs, most of the females arising from fertilized eggs; azygous, or impaternate, females occur sporadically. From the bisexual population a thelyotokous strain has arisen that is not distinguishable by cytological comparison; the females of both arrhenotokous and thelyotokous races are diploid; no diploid males were found. The haplo-diploid relationship of male to female was confirmed; male haploidy has become established by adaptive modifications in meiosis, as indicated in the cytological details given.