bluuebunny/crossref_metadata_2025 huggingface dataset:
Elephant Teeth from the Atlantic Continental Shelf
Authors: Whitmore Frank C. , Emery K. O. , Cooke H. B. S. , Swift Donald J. P.
Published: October 2006

Teeth of mastodons and mammoths have been recovered by fishermen from at least 40 sites on the continental shelf as deep as 120 meters. Also present are submerged shorelines, peat deposits, lagoonal shells, and relict sands. Evidently elephants and other large mammals ranged this region during the glacial stage of low sea level of the last 25,000 years.
Adenovirus Tumorigenesis: Role of the Viral Genome in Determining Tumor Morphology
Authors: Strohl William A. , Rabson Alan S. , Rouse Harriet
Published: October 2006

Adenovirus type 12 transforms the fibroblastic BHK21 (baby hamster kidney) cell line into rounded or cuboidal cells that give rise in hamsters to undifferentiated small cell sarcomas indistinguishable from those induced in newborn hamsters by inoculation of the virus itself. In contrast. cells from this line transformed by polyoma virus retain their fibroblastic morphology and induce fibrosarcomas in hamsters. This suggests that the morphology of tumors induced by the adenovirus-transformed cells from this line may be determined by the viral genome and that such a mechanism may also explain the remarkably uniform microscopic appearance which seems to characterize tumors induced in hamsters by direct inoculation of adenovirus type 12.
Minor Element Composition of Ferromanganese Nodules
Authors: Barnes Steven S.
Published: October 2006

Mineralogical and chemical analyses performed on 67 ferromanganese nodules from widely varying locations and depths within the marine environment indicate that the minor element composition is controlled by the mineralogy, and that the formation of the mineral phases is depth dependent.
Modulation of Elicited Behavior by a Fixed-Interval Schedule of Electric Shock Presentation
Authors: Morse W. H. , Mead Regina N. , Kelleher R. T.
Published: October 2006

Responding elicited in the squirrel monkey by electric shocks presented every 60 seconds was gradually altered in temporal patterning, especially when the shock was also produced by responses under a 30-second fixed-interval schedule. The initially elicited pattern of maximal responding just after each shock was altered by the recurrent shock and by the added fixed-interval schedule to a pattern of maximal responding just before each shock. Most shocks were produced by responses and the response pattern was maintained for several months, but little responding occurred when shocks were omitted.
Postglacial Change in Sea Level in the Western North Atlantic Ocean
Authors: Redfield Alfred C.
Published: October 2006

Radioactive carbon determinations of the age of peat indicate that at Bermuda, southern Florida, North Carolina, and Louisiana the relative sea level has risen at approximately the same rate, 2.5 × 10
-3
foot per year (0.76 × 10
-3
meter per year), during the past 4000 years. It is proposed tentatively that this is the rate of eustatic change in sea level. The rise in sea level along the northeastern coast of the United States has been at a rate much greater than this, indicating local subsidence of the land. Between Cape Cod and northern Virginia, coastal subsidence of 13 feet appears to have occurred between 4000 and 2000 years ago and has continued at a rate of about 1 × 10
-3
foot per year since then. On the northeastern coast of Massachusetts, subsidence of 6 feet occurred between 4000 and 3000 years ago; since then sea level has risen at about the eustatic rate. Between 12,000 and 4000 years ago, sea level rose at an average of about 11 × 10
-3
foot per year. The part played by local subsidence or temporary departures from the average rate during this period is uncertain.
Cytoplasmic and Chloroplast Ribosomes of
Chlamydomonas
: Ultracentrifugal Characterization
Authors: Sager Ruth , Hamilton Mary G.
Published: October 2006

Ribosomes isolated from the cytoplasmic and chloroplast fractions of
Chlamydomonas
were characterized in the ultracentrifuge. The cytoplasmic ribosomes belong to the 80
S
class of ribosomes, and, like animal ribosomes, dissociate to 60, 50, and 40
S
subunits. However, like the ribosomes of microorganisms, they contain smaller RNA's, 24 and 16
S
, and require 0.01 mole of magnesium ions per liter for stability. Chloroplast ribosomes are 70
S
like those of higher plants but are very unstable. A stable 50
S
subunit has been observed.
Fossiliferous Bauxite in Glacial Drift, Martha's Vineyard, Massachusetts
Authors: Kaye Clifford A.
Published: October 2006

Pebbles of pisolitic bauxite occur in Pleistocene drift on Martha's Vineyard. The bauxite contains plant remains and relict quartz and was derived from plant-bearing sediments, probably from the preglacial coastal plain of New England. The preservation of plant tissue suggests that bauxitization took place beneath, rather than above, the water table, as generally believed. This occurrence of bauxite is the northernmost known in eastern North America and suggests the possible existence of undiscovered deposits in the northern coastal plain.
Lysosomal Enzyme Inhibition by Trypan Blue: A Theory of Teratogenesis
Authors: Beck F. , Lloyd J. B. , Griffiths A.
Published: October 2006

A mechanism of mammalian teratogenesis involving inhibition of embryotrophic nutrition is suggested and exemplified by the action of trypan blue on pregnant rats. There is evidence for the localization of trypan blue in heterolysosomes of the epithelium of the visceral yolk sac, and our experiments indicate that the dye is an inhibitor of a selection of hydrolytic enzymes present in lysosomal fractions from homogenates of rat visceral yolk sac. It seems likely that trypan blue inhibits the intracellular digestion of embryotroph by the visceral yolk-sac epithelium; the conceptus may therefore be deprived of essential nutrients at critical stages of development.
Globin Composition and Synthesis of Hemoglobins in Developing Fetal Mice Erythroid Cells
Authors: Fantoni Antonio , Bank Arthur , Marks Paul A.
Published: October 2006

Fetal mouse erythropoiesis proceeds initially in yolk-sac blood islands (8 to 12 days) and, subsequently, in liver (12 to at least 16 days). Yolksac cells synthesize three hemoglobins, Hb E
I
, Hb E
II
and Hb E
III
. Hb E
I
has x- and y-globin chains; Hb E
II
has α and y; HB E
III
, α and z. No detectable β-globin is formed in these cells. Liver erythroid cells form only adult hemoglobin, composed of α- and β-chains.
Knoll and Sediment Drift near Hudson Canyon
Authors: Lowrie Allen , Heezen Bruce C.
Published: October 2006

A parallel-bedded accumulation of sediments forms a low ridge on the upcurrent side of a partially moated knoll. These sediments were deposited beneath a southwestward-flowing current where it is locally decelerated by the obstructing knoll.
Indoleacetic Acid Oxidase Activity of Apoperoxidase
Authors: Siegel B. Z. , Galston A. W.
Published: October 2006

The conventional activity of electrophoretically purified horseradish peroxidase toward guaiacol, pyrogallol, 2,6-dimethoxyphenol, and benzidine is abolished by removal of the heme prosthetic group with a mixture of cold acetone and hydrogen chloride. The apoenzyme, though devoid of peroxidase activity, retains its activity as an indoleacetic acid oxidase when it is supplied with 10-5mole of manganous ion and 2,4-dachlorophenol per liter. This oxidase activity is cyanide-sensitive; azide also inhibits under specific conditions of bothpH and cofactor concentration. Partial restoration of the peroxidase activity by recombination of apoprotein with heme produces no effect on the oxidase activity, except that cofactors are no longer absolutely required. Therefore, it appears that the activity of peroxidase as an indoleacetic acid oxidase need not directly involve the heme prosthetic group, or that manganous ions and dichlorophenol can substitute for the heme group in the reaction between indoleacetic acid and oxidase.
Genetic Background and Expressivity of Histocompatibility Genes
Authors: Silvers Willys K. , Billingham R. E.
Published: October 2006

A difference in the reactivity of F
1
hybrid female mice to skin grafts from male donors of each of their parental strains suggests that the genetic background can influence the efficacy of the Y antigen to elicit rejection of the graft.
Variations in the Isotopic Composition of Carbon in Urban Atmospheric Carbon Dioxide
Authors: Friedman L. , Irsa A. P.
Published: October 2006

Measurement of the abundance of atmospheric carbon dioxide as an indicator of air pollution has been of very limited value because of variations in urban areas in the substantial concentration of natural carbon dioxide produced from combustion and noncombustion (natural) sources. A solution to this problem is the use of precise isotopic assay of ratios of carbon-13 to carbon-12 in atmospheric carbon dioxide. There is very little variation of carbon isotopic composition in samples taken over rural or urban areas where rapid mixing and diffusion of gaseous combustion products is possible. Significant differences in this composition in samples taken at centrally located points at street level in the lower Manhattan business district show an increase in concentration of atmospheric carbon dioxide of roughly 20 percent produced primarily by automobile exhaust.
Reagentless Substrate Analysis with Immobilized Enzymes
Authors: Updike S. J. , Hicks G. P.
Published: October 2006

By coupling an immobilized enzyme system with an electrochemical sensor, the reagent requirement for this glucose method is eliminated. Miniaturization and a further simplification of the instrumentation for the continuous analysis of glucose is achieved.
Pediplain in Northern Chile and the Andean Uplift
Authors: Galli-Olivier Carlos
Published: October 2006

A pediplain in the Chilean Atacama Desert formed during Oligocene and Miocene time when the aridity of the region started and was later displaced by north-trending faults associated with the Andean uplift. Block basins and some horsts were later concealed by Upper Tertiary and Quaternary orogenic sediments and ignimbrites.
Stable Magnetic Remanence in Antiferromagnetic Goethite
Authors: Strangway D. W. , McMahon B. E. , Honea R. M.
Published: October 2006

Goethite, known to be antiferromagnetic, acquires thermoremanent magnetization at its Neel temperature of 120°C. This remanence, extremely stable, is due to the presence of unbalanced spins in the antiferromagnetic structure; the spins may result from grain size, imperfections, or impurities.
Sedimentary Phosphate Method for Estimating Paleosalinities
Authors: Nelson Bruce W.
Published: October 2006

The widespread occurrence of sedimentary phosphate in argillaceous sediments provides the basis for a new method of paleosalinity estimation. Sedimentary phosphate contains iron- and calcium-phosphate fractions, the relative proportions of which are sensitive to salinity of the water at sites of deposition. The sedimentary phosphate method provides direct estimates of paleosalinity throughout the freshwater to marine range.
Tiliqua scincoides
: Temperature-Sensitive Units in Lizard Brain
Authors: Cabanac M. , Hammel T. , Hardy J. D.
Published: October 2006

Extracellular action potentials were recorded from units in the preoptic area of the brain of the Australian blue-tongued Skink (
Tiliqua scincoides
) during periods of local heating and cooling of the brain (20° to 36°C) with water-perfused thermodes. In this temperature range most spontaneously firing neurons were temperature-insensitive, but eight showed sensitivity to the thermal stimulus. Five warm neurons increased their activity when the brain temperature was raised, and three cold neurons showed increased activity with fall in temperature.
Coccoliths as Paleoclimatic Indicators of Pleistocene Glaciation
Authors: McIntyre Andrew
Published: October 2006

Selected species of Coccolithophoridae from recent sediments and mid-Wisconsin glacial sediments of the North Atlantic were examined in an attempt to determine cooling effects. All species showed a definite shift southward during the glacial period. The average shift in this planktonic population was 15 degrees of latitude, with the greatest change in the eastern Atlantic. A paleoisotherm map can be drawn on the basis of the temperature boundaries of coccolithophorids. The species boundaries indicate a possible shift in position of the subtropical gyral to a glacial position roughly parallel to the 33-degree line of latitude.
Mariner V Flight Past Venus
Authors: Snyder Conway W.
Published: October 2006

On 19 October 1967 the Mariner V spacecraft passed by Venus 10,151 kilometers from the center of the planet; the gravitational field, atmosphere, ionosphere, hydrogen corona, and interaction with the solar wind were observed.
Induction and Survival of Hemoglobin-Less and Erythrocyte-Less Tadpoles and Young Bullfrogs
Authors: Flores Gustavo , Frieden Earl
Published: October 2006

Injection of two 25-microgram-per-gram doses of the hemolytic agent phenylhydrazine reduced the hemoglobin level and the erythrocyte count to less than 1 percent of normal tadpole and young bullfrog blood. These anemic animals survive for weeks with little change in overall metabolism. A slow recovery of hemoglobin levels was observed. The implications of this observation for comparative biochemistry are considered.
Cosmic Ray-Produced Radionuclides as Tracers of Atmospheric Precipitation Processes
Authors: Wogman N. A. , Thomas C. W. , Cooper J. A. , Engelmann R. J. , Perkins R. W.
Published: October 2006

Through recent developments in instrumental analysis it is now possible to measure with good precision the rainwater concentrations of five short-lived radionuclides which are produced by cosmic ray spallation of atmospheric argon. These measurements provide a method for studying the in-cloud nucleation times and aerosol scavenging efficiencies, and promise to provide information on short-term processes which occur in rain and snow formation.
Tyrosine Enteroreceptor of
Hydra
: Its Function in Eliciting a Behavior Modification
Authors: Blanquet Richard S. , Lenhoff Howard M.
Published: October 2006

Hydra that still contain partially digested food in their gastrovascular cavities, undergo a modified feeding response when they ingest additional prey. A localized constriction is formed just below the sites of tentacle attachment, preventing the loss of gastrovascular contents. This response involves the interaction of an ectodermal receptor system for glutathione and an endodermal receptor system for tyrosine.
Evolution of Paleozoic Marine Invertebrate Communities
Authors: Bretsky Peter W.
Published: October 2006

Communities of Paleozoic shelf invertebrates underwent varied rates of change in faunal composition. Notable changes took place during Late Devonian-Early Mississippian time and were most noticeable in offshore brachiopod-dominated communities. Near-shore molluscan communities remained relatively stable throughout the Paleozoic.
Response of
Ips confusus
to Synthetic Sex Pheromones in Nature
Authors: Wood David L. , Browne Lloyd E. , Bedard William D. , Tilden Paul E. , Silverstein Robert M. , Rodin J. Otto
Published: October 2006

The first flight response of bark beetles to synthetic sex pheromones under natural conditions is reported. Two insect species predaceous on this bark beetle also responded. The synthetic compounds delivered in an airstream from a substrate of Carbowax 20M on Chromosorb A appear to elicit the same response as the natural attractant from male-infested bolts of ponderosa pine elicits.
Genetic Control of Drug Levels in Man: Phenylbutazone
Authors: Vesell Elliot S. , Page John G.
Published: October 2006

Phenylbutazone was administered to seven pairs of identical (monozygotic) twins and to seven pairs of fraternal (dizygotic) twins. Individual half-lives ranged from 1.2 to 7.3 days. Subjects with identical genotypes (monozygotic twins) exhibited very similar phenylbutazone half-lives; significantly greater differences in half-life occurred in dizygotic twins. The previously established large variations among individuals in phenylbutazone metabolism appear to be genetically, rather than environmentally, determined.
Galactose Oxidation in the Design of Immunogenic Vaccines
Authors: Zheng Biao , Brett Sara J. , Tite John P. , Lifely M. Robert , Brodie Thomas A. , Rhodes John
Published: October 2006

Potent immunological adjuvants are urgently required to complement recombinant and synthetic vaccines. However, it has not been possible to derive new principles for the design of vaccine adjuvants from knowledge of the mechanism of immunogenicity. Carbonyl-amino condensations, which are essential to the inductive interaction between antigen-presenting cells and T helper cells, were tested as a target for the enhancement of immune responses. Enzymic oxidation of cell-surface galactose to increase aminereactive carbonyl groups on murine lymphocytes and antigen-presenting cells provided a potent, noninflammatory method of enhancing the immunogenicity of viral, bacterial, and protozoal subunit vaccines in mice.
Metacontrast and Evoked Potentials: A Reappraisal
Authors: Vaughan Herbert G. , Silverstein Leonard
Published: October 2006

Stimulation of the parafoveal retina may give rise to visual evoked responses generated in large part by stray light impinging upon the fovea. This effect appears to account for the absence of changes in the visual evoked response to parafoveal stimulation during metacontrast suppression. When the central retina is directly stimulated, the spatiotemporal interactions associated with brightness suppression during metacontrast may be readily demonstrated in a late component of the visual evoked response.
Vitrification Temperature of Water
Authors: Yannas Ioannis
Published: October 2006

The vitrification temperature (

T
g

) of water is an elusive quantity because of the great difficulty in supercooling water sufficiently without initiating its crystallization. Water depresses the vitrification temperature of glycerol (184°K) monotonously, and this property has been used for derivation of an estimate of its

T
g

. The result, 127° ± 4°K (-146° ± 4°C), is the temperature below which water presumably exists as a brittle, glassy substance.
Microcirculation: Loss of an Enzyme Activity in Chickens with Hereditary Muscular Dystrophy
Authors: Ashmore C. R. , Doerr L. , Somes R. G.
Published: October 2006

Histochemical localization of an alkaline phosphatase, with α-naphthyl phosphate used as substrate, shows that activity in breast muscle from normal chickens is restricted to the microvasculature. In chickens with hereditary muscular dystrophy, this enzyme activity disappears from capillaries and small arterioles before degeneration of muscle fibers is detectable. This loss is retarded in myopathic chickens that have received oxygen therapy.
Plantlets from Aspen Tissue Cultures
Authors: Winton Lawson L.
Published: October 2006

After 2 weeks in the dark, leafy shoots were initiated on subcultured callus tissue of triploid quaking aspen on Wolter's medium without auxin and with 6-benzylaminopurine at 0.05, 0.10, 0.15, or 0.20 milligram per liter substituted for kinetin. Shoots transferred to Wolter's medium under light (323 milliphots) grew large roots and were isolated as plantlets.
Propanil Hydrolysis: Inhibition in Rice Plants by Insecticides
Authors: Matsunaka Shooichi
Published: October 2006

Hydrolysis of the herbicide propanil (3′,4′-dichloropropionanilide) by rice plants is inhibited by insecticides. The inhibitory activity of an organophosphate such as paraoxon in vivo and in vitro is significantly stronger than that of an organothiophosphate such as parathion. The injury to rice plants by insecticides sprayed on them with propanil seems to be caused by the inhibition of the propanil detoxifying enzyme.
Human Brain: Left-Right Asymmetries in Temporal Speech Region
Authors: Geschwind Norman , Levitsky Walter
Published: October 2006

We have found marked anatomical asymmetries between the upper surfaces of the human right and left temporal lobes. The planum temporale (the area behind Heschl's gyrus) is larger on the left in 65 percent of brains; on the right it is larger in only 11 percent. The left planum is on the average one-third longer than the right planum. This area makes up part of the temporal speech cortex, whose importance is well established on the basis of both anatomical findings in aphasic patients and cortical stimulation at operation.
Triops
(Entomostraca) Eggs Killed Only by Boiling
Authors: Carlisle D. B.
Published: October 2006

Temporary rainpools near Khartoum, Sudan, are inhabited by the notostracan crustacean
Triops
which completes its life cycle within 4 weeks. The annual rains fall in late summer, and throughout the winter and early summer the eggs of
Triops
remain in the dried mud or dust where they may be exposed to temperatures up to 80°C. Laboratory experiments show that they can withstand temperatures up to within 1°C of boiling, but are killed in partial vacuum by 70°C, at atmospheric pressure by 100°C, or under pressure by 105°C. Exposure to high temperature seems to be necessary to break the egg diapause.
Enzymatic Synthesis of Melatonin in Avian Pineal Body: Extraretinal Response to Light
Authors: Lauber Jean K. , Boyd James E. , Axelrod Julius
Published: October 2006

In the chick pineal body, activity of the melatonin-forming enzyme hydroxyindole-
O
-methyl transferase is greater in the light than in darkness. Neither bilateral enucleation of the eyes nor sympathetic denervation prevented this light-induced elevation of enzyme activity. This fact indicates that in the bird, in contrast to mammals, neither the retinas nor sympathetic innervation of the pineal body are essential for environmental control of melatonin formation.
High-Resolution Electron Microscopy of Muscovite
Authors: Brown John L. , Rich Charles I.
Published: October 2006

Images of the (001) planes of muscovite were observed by electron microscopy after embedment of clay-size flakes in epoxy resin and sectioning by ultramicrotome. Dislocation or growth planes were indicated. Incomplete exchange of potassium for barium produced zones with 20-angstrom periodicity, suggesting regular interstratification.
Rana pipiens
Complex: Mating Call Structure and Taxonomy
Authors: Littlejohn M. J. , Oldham R. S.
Published: October 2006

Geographic variability in call structure indicates that four largely allopatric populations of leopard frogs are present in the central United States. These forms appear to maintain their distinctness in narrow zones of sympatry, and most adult males can be separated morphologically. It is suggested that the four forms represent distinct species and that the idea of gradual clinal variability in one wide-ranging species is wrong.
Sea Levels during the Past 35,000 Years
Authors: Milliman John D. , Emery K. O.
Published: October 2006

A sea-level curve of the past 35,000 years for the Atlantic continental shelf of the United States is based on more than 80 radiocarbon dates, 15 of which are older than 15,000 years. Materials include shallow-water mollusks, oolites, coralline algae, beachrock, and salt-marsh peat. Sea level 30,000 to 35,000 years ago was near the present one. Subsequent glacier growth lowered sea level to about -130 meters 16,000 years ago. Holocene transgression probably began about 14,000 years ago, and continued rapidly to about 7000 years ago. Dates from most shelves of the world agree with this curve, suggesting that it is approximately the eustatic curve for the period.
Increased Osteoclast Development After Estrogen Loss: Mediation by Interleukin-6
Authors: Jilka Robert L. , Hangoc Giao , Girasole Giuseppe , Passeri Giovanni , Williams Daniel C. , Abrams John S. , Boyce Brendan , Broxmeyer Hal , Manolagas Stavros C.
Published: October 2006

Osteoclasts, the cells that resorb bone, develop from hematopoietic precursors of the bone marrow under the control of factors produced in their microenvironment. The cytokine interleukin-6 can promote hematopoiesis and osteoclastogenesis. Interleukin-6 production by bone and marrow stromal cells is suppressed by 17β-estradiol in vitro. In mice, estrogen loss (ovariectomy) increased the number of colony-forming units for granulocytes and macrophages, enhanced osteoclast development in ex vivo cultures of marrow, and increased the number of osteoclasts in trabecular bone. These changes were prevented by 17β-estradiol or an antibody to interleukin-6. Thus, estrogen loss results in an interleukin-6-mediated stimulation of osteoclastogenesis, which suggests a mechanism for the increased bone resorption in postmenopausal osteoporosis.
In Vivo Calcium Elevations in Thymocytes with T Cell Receptors That Are Specific for Self Ligands
Authors: Nakayama Toshinori , Ueda Yuji , Yamada Hidehiro , Shores Elizabeth W. , Singer Alfred , June Carl H.
Published: October 2006

Selection of the T cell receptor (TCR) repertoire in the thymus probably involves TCR-mediated signals transduced in developing thymocytes after interaction with thymic stromal cells bearing self ligands. TCR-transduced signals should have identifiable consequences that would distinguish thymocytes whose TCRs have been engaged by self ligands from those whose TCRs have not. Among thymocytes expressing a transgenic TCR of defined specificity, a large number had elevated intracellular calcium concentrations but only when resident in a negatively selecting thymus in which their self ligand was expressed. Thus, developing thymocytes are stimulated by endogenous ligands in vivo to mobilize intracellular calcium, and increased intracellular calcium concentrations may reflect the consequences of intrathymic signaling associated with thymic negative selection.
Moving Flame Experiment with Liquid Mercury: Possible Implications for the Venus Atmosphere
Authors: Schubert G. , Whitehead J. A.
Published: October 2006

A bunsen flame rotated under a cylindrical annulus filled with liquid mercury forces the liquid mercury to rotate in a direction counter to that of the rotating flame. The rate of rotation of the liquid is several times greater than that of the flame. This observation may provide an explanation for the high velocities of apparent cloud formations in the upper atmosphere of Venus.
Macroglobulin Structure: Homology of Mu and Gamma Heavy Chains of Human Immunoglobulins
Authors: Wikler Maurice , Köhler Heinz , Shinoda Tomotaka , Putnam F. W.
Published: October 2006

The amino acid sequence of fragments obtained by cyanogen bromide cleavage of the mu-chain of a human γM-globulin is homologous to the NH
2
-terminal sequences of the gamma-chain of human and rabbit γG-globulins and is related to that of human light chains. This supports the hypothesis that light and heavy chains evolved from a common ancestral gene.
Steady Potential Correlates of Positive Reinforcement: Reward Contingent Positive Variation
Authors: Marczynski T. J. , York J. L. , Hackett J. T.
Published: October 2006

A positive reinforcement with food produced high-voltage bursts of alpha activity over the posterior marginal gyrus in a cat deprived of food and water. This synchronization was always associated with a large (180 to 300 microvolt), positive steady potential shift comparable to that occurring during the onset of sleep. Since this shift was contingent upon the relative appropriateness and desirability of food reward, it was termed reward contingent positive variation.
Suspended Particulate Matter: Concentration in the Major Oceans
Authors: Jacobs Marian B. , Ewing Maurice
Published: October 2006

Quantitative data from over 500 concentrates of suspended particulate material has been summarized statistically for the Atlantic, Pacific, and Indian oceans, the Gulf of Mexico, and the Caribbean Sea. From clear ocean water a majority of samples were in the range of 0 to 9.9 milligrams per 200 liters and the next largest number were in the range of 10 to 19.9 milligrams per 200 liters. Certain areas of cloudy or nepheloid water, observed photographically, contain relatively more samples in heavier concentration ranges and have larger mean values than clear ocean water.
Sedimentary Rock Types: Relative Proportions as a Function of Geological Time
Authors: Garrels Robert M. , Mackenzie Fred T.
Published: October 2006

Proportions of sedimentary rock types remaining today differ from period to period. These differences may be chiefly the result of differential rates of deposition and erosion of the various components of the rocks. Lower percentages of limestones and evaporites in Precambrian rocks than in post-Precambrian rocks probably represent selective loss of these more easily removable components from the original deposits.
Xenon: Effect on Radiation Sensitivity of HeLa Cells
Authors: Schulz R. J. , Markoe A. M. , Anigstein R.
Published: October 2006

HeLa cells, plated onto plastic petri dishes, were exposed to various atmospheres composed of air and carbon dioxide; helium, oxygen, and carbon dioxide; and xenon, oxygen, and carbon dioxide in a pressure vessel. Survival curves with x-rays, 280 kilovolts (peak), show that air and helium have the same effect, but that xenon potentiates x-irradiation to the extent that the dose to produce a given level of survival with xenon is 0.58 of the dose required with air.
Fig Wasps: Mechanism of Pollen Transfer
Authors: Ramírez B. William
Published: October 2006

The fig (
Ficus
) is absolutely dependent upon pollination by minute agaonid wasps for development of fertile seeds. In some species of the wasp genera
Agaon
,
Allotriozoon
,
Blastophaga
,
Ceratosolen
,
Elisabethiella
,
Liporrhopalum
, and
Pleistodontes
, the females possess concavities ("corbiculae") to carry pollen. The New World
Tetrapus
and some Old World
Blastophaga
lack pollen-carrying structures and may carry pollen dusted over the body or in the digestive tract.
Oxytocin: Crystal Date of a Seleno Analog
Authors: Chiu Celia C. , Schwartz Irving L. , Walter Roderich
Published: October 2006

The sulfur atom in position 6 of deamino-oxytocin (1-β-mercapto-propionic acid-oxytocin) was replaced by selenium. The crystals of the resulting deamino-6-seleno-oxytocin are similar to those of the "wet" form of deamino-oxytocin, but they are stable upon prolonged exposure to air.
Estimating Proportions in Petrographic Mixing Equations by Least-Squares Approximation
Authors: Bryan W. B. , Finger L. W. , Chayes F.
Published: October 2006

Petrogenetic hypotheses involving fractional crystallization, assimilation, or mixing of magmas may be expressed and tested as problems in least-squares approximation. The calculation uses all of the data and yields a unique solution for each model, thus avoiding the ambiguity inherent in graphical or trial-and-error procedures. The compositional change in the 1960 lavas of Kilauea Volcano, Hawaii, is used to illustrate the method of calculation.
Spin Filter Culture: The Propagation of Mammalian Cells in Suspension
Authors: Himmelfarb P. , Thayer P. S. , Martin H. E.
Published: October 2006

A spin filter device has been used for the propagation in vitro of cells of mouse leukemia L1210 to densities approaching 10
8
cells per milliliter. By manipulation of flow rates, cells may be exposed to exponentially declining drug concentrations with half-times of 1.5 hours or less, providing a more realistic parallel to in vivo drug treatment than is obtained by other culture methods.
Dye-Sensitized Photooxidation of the
Escherichia coli
Ribosome
Authors: Garvin Robert T. , Julian Gordon R. , Rogers Samuel J.
Published: October 2006

Chemical modification of ribosomes from
Escherichia coli
by oxidation in the presence of selected photosensitizing dyes causes a rapid loss of their amino acid-incorporating ability. By comparing the efficiency of dyes that sensitize the photooxidation of either guanine in ribonucleic acid or amino acid residues in proteins, inactivation of one or more functional ribosomal proteins is inferred.
Digitoxin Poisoning: Prevention by Spironolactone
Authors: Selye Hans , Krajny Miloslav , Savoie Laurent
Published: October 2006

Spironolactone (Aldactone ®) protects the rat against the production of myocardial necroses and other manifestations of digitoxin poisoning.
Anorthosite Belts, Continental Drift, and the Anorthosite Event
Authors: Herz Norman
Published: October 2006

Most anorthosites lie in two principal belts when plotted on a predrift continental reconstruction. Anorthosite ages in the belts cluster around 1300 ± 200 million years and range from 1100 to 1700 million years. This suggests that anorthosites are the product of a unique cataclysmic event or a thermal event that was normal only during the earth's early history.
Nitrogen Fixation in Some Anoxic Lacustrine Environments
Authors: Brezonik Patrick L. , Harper Carol L.
Published: October 2006

Low rates of acetylene reduction to ethylene in water samples from two dystrophic lakes indicate the presence of nitrogenase and in situ nitrogen fixation. Highest rates were found in anoxic water from the aphotic zone. Environmental conditions in these lakes suggest the agents of fixation were bacteria.
Transplantation of Pluripotential Nuclei from Triploid Frog Tumors
Authors: McKinnell Robert G. , Deggins Beverly A. , Labat Deidre D.
Published: October 2006

Renal tumors were produced by injection of a cell fraction of a tumor into triploid tadpoles of
Rana pipiens
before they began feeding. Triploid tumor cells were dissociated and transplanted into activated and enucleated eggs. Pluripotency of the implanted nuclei was evidenced by the formation of swimming triploid tadpoles.
Phosphonomycin, a New Antibiotic Produced by Strains of
Streptomyces
Authors: Hendlin D. , Stapley E. O. , Jackson M. , Wallick H. , Miller A. K. , Wolf F. J. , Miller T. W. , Chaiet L. , Kahan F. M. , Foltz E. L. , Woodruff H. B. , Mata J. M. , Hernandez S. , Mochales S.
Published: October 2006

Phosphonomycin is a newly discovered antibiotic produced by streptomycetes. It is effective, when administered by the oral route, to mice infected with Gram-positive or Gram-negative microorganisms. The antibiotic is bactericidal and inhibits cell-wall synthesis.
Solar-Type Xenon: A New Isotopic Composition of Xenon in the Pesyanoe Meteorite
Authors: Marti Kurt
Published: October 2006

Xenon in the Pesyanoe meteorite is a mixture of several components. Solar-type xenon is a new component deficient in the neutron-rich isotopes as compared to both trapped chondritic and terrestrial atmospheric xenon.
Blind River Dolphin: First Side-Swimming Cetacean
Authors: Herald Earl S. , Brownell Robert L. , Frye Fredric L. , Morris Elkan J. , Evans William E. , Scott Alan B.
Published: October 2006

The blind river dolphin (
Platanista gangetica
), first written about by Pliny the Elder in A.D. 72, was found (10 November 1968) to be the first known side-swimming cetacean. The rudimentary eye lacks the lens, but anatomical evidence suggests that the eye may serve as a light sensor. The underwater sound emissions of this species, although similar to those of the Amazon River dolphin (
Inia geoffrensis
), appear to be produced constantly.
Imidodiphosphate and Pyrophosphate: Possible Biological Significance of Similar Structures
Authors: Larsen Marlin , Willett Roger , Yount Ralph G.
Published: October 2006

The structure of sodium imidodiphosphate has been determined by single crystal x-ray diffraction. The P-N-P bond angle (127.2°) and P-N bond distance (1.68 angstroms) are remarkably similar to newly refined values for the P-O-P bond angle (128.6°) and the bridging P-O bond distance (1.63 angstroms) of sodium pyrophosphate. This close similarity may explain why P-N-P linkages in algal "polyphosphates" escaped detection until recently and why adenosine triphosphate analogs with this linkage mimic adenosine triphosphate so closely.
Shock and Thermal Metamorphism of Basalt by Nuclear Explosion, Nevada Test Site
Authors: James Odette B.
Published: October 2006

Olivine trachybasalt metamorphosed by nuclear explosion is classified into categories of progressive metamorphism: (i) Weak. Plagioclase is microfractured, and augite contains fine twin lamellae. (ii) Moderate. Plagioclase is converted to glass, and mafic minerals show intragranular deformation (undulatory extinction, twin lamellae, and, possibly, deformation lamellae), but rock texture is preserved. (iii) Moderately strong. Plagioclase glass shows small-scale flow, mafic minerals are fractured and show intragranular deformation, and rocks contain tension fractures. (iv) Strong. Plagioclase glass is vesicular, augite is minutely fractured, and olivine is coarsely fragmented, shows mosaic extinction, distinctive lamellar structures, and is locally recrystallized. (v) Intense. Rocks are converted to inhomogeneous basaltic glass.
Isolation of an Active Human Transposable Element
Authors: Dombroski Beth A. , Mathias Stephen L. , Nanthakumar Elizabeth , Scott Alan F. , Kazazian Haig H.
Published: October 2006

Two de novo insertions of truncated L1 elements into the factor VIII gene on the X chromosome have been identified that produced hemophilia A. A full-length L1 element that is the likely progenitor of one of these insertions was isolated by its sequence identity to the factor VIII insertion. This L1 element contains two open-reading frames and is one of at least four alleles of a locus on chromosome 22 that has been occupied by an L1 element for at least 6 million years.
Leaf Hydraulic System: Rapid Epidermal and Stomatal Responses to Changes in Water Supply
Authors: Raschke Klaus
Published: October 2006

The epidermis of the leaf of
Zea mays
transmits changes in water potential in the water supply of the leaf to the stomata within 0.1 second. Reduction in water supply can cause the subsidiary cells surrounding the stomata to collapse within 1.5 minutes, and the epidermis to shrink to one-third of its original thickness within 20 minutes.
Water in the Earth's Mantle: Melting Curves of Basalt-Water and Basalt-Water-Carbon Dioxide
Authors: Hill Robin E. T. , Boettcher A. L.
Published: October 2006

At depths below about 45 kilometers in the earth, the presence of high proportions of carbon dioxide does not significantly affect the temperature of the beginning of melting of basalt-water compositions. Water must be present only in trace amounts in the solid part of the silicate mantle if it contains appreciable proportions of basaltic composition.
Crustal Plates in the Central Atlantic
Authors: Ball M. M. , Harrison C. G. A.
Published: October 2006

Various people have proposed that North and South America are a part of a gigantic crustal plate within which little differential movement is taking place. Considerations of the size of this postulated plate and the pattern of seismicity around the Caribbean indicate that it is in fact two plates, separated in the region between the Lesser Antilles and the Mid-Atlantic Ridge. Many of the offsets of the Mid-Atlantic Ridge opposite the Caribbean are the result of differential spreading rates and the westward continuations of the fracture zones extending from these offsets are active left-lateral faults.
Mites and Commercial Extracts of House Dust
Authors: Wharton G. W.
Published: October 2006

North American and European house dust mites have been found in the dusts used in the manufacture of commercial extracts of house dust.
Neuroendocrine Control of Ecdysis in Silkmoths
Authors: Truman James W. , Riddiford Lynn M.
Published: October 2006

An adult moth sheds its pupal skin only during a specific period of the day. The brain is necessary for the synchronization of this behavior with the environmental photoperiod. This function is fully preserved when all the brain's nervous connections are severed or when a "loose" brain is transplanted into the tip of the abdomen. By appropriate experiments it was possible to show that the entire mechanism is brain-centered. The components include a photoreceptor mechanism, a clock, and a neuroendocrine output. The clock-controlled release of the hormone acts on the central nervous system to trigger a species-specific behavior pattern which culminates in ecdysis.
Neuronal Correlates of Habituation and Dishabituation of the Gill-Withdrawal Reflex in
Aplysia
Authors: Kupfermann Irving , Castellucci Vincent , Pinsker Harold , Kandel Eric
Published: October 2006

We have examined the neural correlates of habituation and dishabituation of the gill-withdrawal reflex in
Aplysia
. We obtained intracellular recordings from identified gill motor neurons in the abdominal ganglion of a semi-intact preparation of
Aplysia
while we simultaneously recorded behavior responses of the gill. Habituation and dishabituation were not due to peripheral changes in either the sensory receptors or the gill musculature but were caused by changes in the amplitude of the excitatory synaptic potentials produced at the gill motor neurons.
Heteroplasmy Suggests Limited Biparental Inheritance of
Mytilus
Mitochondrial DNA
Authors: Hoeh Walter R. , Blakley Karen H. , Brown Wesley M.
Published: October 2006

Strict maternal inheritance of mitochondrial DNA is commonly observed in animals. There is usually only one mitochondrial DNA population (homoplasmy) within an individual. Mussels of the
Mytilus edulis
species group appear to be exceptions in both respects. Of 150
Mytilus
individuals examined, 85 were heteroplasmic. Mitochondrial DNA types within heteroplasmic individuals differed greatly; in one comparison, the inferred sequence difference was 20 ± 5 percent. Homoplasmic individuals with mitochondrial DNA similar to the heteroplasmic mitochondrial DNA types were found. These observations are best explained by the hypothesis that biparental inheritance of mitochondrial DNA can occur in
Mytilus
.
Arsenic in Detergents: Possible Danger and Pollution Hazard
Authors: Angino E. E. , Magnuson L. M. , Waugh T. C. , Galle O. K. , Bredfeldt J.
Published: October 2006

Arsenic at a concentration of 10 to 70 parts per million has been detected in several common presoaks and household detergents. Arsenic values of 2 to 8 parts per billion have been measured in the Kansas River. These concentrations are close to the amount (10 parts per billion) recommended by the United States Public Health Service as a drinking-water standard.
Orientation Order of Dipole Molecules in the Surface of Embryonic Droplets
Authors: Abraham Farid F.
Published: October 2006

During the growth of embryonic droplets in an imperfect vapor the surface polar molecules pass from a disordered orientation state to an ordered orientation state, the transition size being on the order of 100 molecules. This transition poses an interesting model problem in the study of order-disorder transitions in the thermodynamics of small systems.
Orotidinuria Induced by Allopurinol
Authors: Fox R. M. , Royse-Smith D. , O'Sullivan W. J.
Published: October 2006

The administration of allopurinol to patients suffering from hyperuricemia and to normal subjects results in increased excretion of the pyrimidine nucleoside orotidine. Evidence is presented for the interference by allopurinol of the de novo biosynthesis of uridine 5′-phosphate in man.
Acetabularia
Chloroplast DNA: Electron Microscopic Visualization
Authors: Green Beverley R. , Burton Hugh
Published: October 2006

Isolated chloroplasts of
Acetabularia mediterranea
, lysed by osmotic shock in a protein monolayer, released large amounts of supercoiled DNA. In some cases, the DNA radiated in large loops from centers of organization. The amount of DNA per chloroplast may be similar to that of a bacterium.
Exposed Guyot from the Afar Rift, Ethiopia
Authors: Bonatti Enrico , Tazieff Haroun
Published: October 2006

A series of originally submarine volcanoes has been found in the Afar Depression. Some of the volcanic structures are morphologically similar to oceanic guyots. One of them consists of strata of finely fragmented and pulverized basaltic glass. The fragmentation of the lava is probably the result of stream explosions taking place during the submarine eruption. The flat top of this guyot is considered to be a constructional feature; by analogy, it is suggested that not all oceanic guyots are necessarily the result of wave truncation of former volcanic islands.
Testing the Vision of Cataract Patients by Means of Laser-Generated Interference Fringes
Authors: Green Daniel G.
Published: October 2006

In a new technique for measuring the visual acuity of cataract patients the light from a laser is used to form interference patterns of variable fineness on the patient's retina. The fineness of the interference pattern that the patient can detect gives an indication of the potential for improved vision. Comparison of this estimate of the potential with the patient's vision after cataract extraction shows that this test can indicate the condition of the fovea behind a cataract.
Limb Movements in a Monotreme (
Tachyglossus aculeatus
): A Cineradiographic Analysis
Authors: Jenkins Farish A.
Published: October 2006

In a walking echidna the principal movement of the humerus is long-axis rotation. The humerus remains approximately perpendicular to the sagittal plane, but the femur is directed anterolaterally at angles from 35° to 50°. In addition to long-axis rotation, the femur elevates and depresses in an arc which usually varies between 40° and 90°. The femoral angle, the femoral elevation and depression, and the plantar contact of the manus beneath the glenoid are features found also in generalized therians.
Defect in DNA Synthesis in Skin of Patients with Xeroderma Pigmentosum Demonstrated in vivo
Authors: Epstein John H. , Fukuyama Kimie , Reed William B. , Epstein William L.
Published: October 2006

Exposure of normal human skin in vivo to ultraviolet irradiation at wavelengths shorter than 320 nanometers stimulated an unscheduled DNA synthesis in all of the cell layers of the epidermis and in the upper dermal fibrocytes. The skin of patients with xeroderma pigmentosum did not show this response. Correlation of these findings with previous tissue culture studies suggests that the defect in repair of the damaged DNA in xeroderma pigmentosum cells occurs in vivo as well as in vitro.
Lycopene Accumulation Induced by 2-(4-Chlorophenylthio)-Triethylamine Hydrochloride
Authors: Coggins C. W. , Henning G. L. , Yokoyama Henry
Published: October 2006

After fruits, roots, or the mycelium of certain plants were treated with 2-(4-chlorophenylthio)-triethylamine hydrochloride, lycopene was detected in the tissue. This is the first known success in causing lycopene to accumulate in a wide range of carotenogenic tissues that normally do not accumulate the pigment at some stage of development. The response should be of value in the study of carotenoid biosynthetic pathways and gene control mechanisms.
Pion Cancer Therapy: Positron Activity as an Indicator of Depth-Dose
Authors: Taylor M. C. , Phillips G. C. , Young R. C.
Published: October 2006

Negative pions are useful for radiation therapy of localized carcinoma because of their large end-of-range energy deposition upon capture in nuclei and the potentially accurate spatial localization of the radiation dose. Accurate determination of the depth of penetration of the pion beam in vivo can be accomplished by counting the back-to-back annihilation gamma rays resulting from positron activity induced by the stopped pions.
Immunoassay of Plasma Low-Density Lipoproteins
Authors: Lees Robert S.
Published: October 2006

An immunoassay was developed for determining the concentration of the protein moiety of the low-density lipoproteins of human plasma. The concentration of this protein in the plasma was variable; it was higher than normal on the average in patients with familial hyperbetalipoproteinemia (type II) and endogenous hyperlipemia (type IV) and lower than normal in patients with fat-induced (type I) and mixed (type V) hyperlipemia. Patients with endogenous hyperlipemia were separable by the immunoassay into those with normal and those with supernormal low-density lipoprotein protein concentration.