bluuebunny/crossref_metadata_2025 huggingface dataset:
Activation of Viruses in Human Tumors by 5-Iododeoxyuridine and Dimethyl Sulfoxide
Authors: Stewart Sarah E. , Kasnic George , Draycott Catherine , Ben Theresa
Published: October 2006

Dimethyl sulfoxide added to cultures first treated with 5-iododeoxyuridine increased C-type virus production approximately tenfold in a human rhabdomyosarcoma cell line. 5-Iododeoxyuridine followed by dimethyl sulfoxide also activated a similar C-type virus in a metastatic tumor from a bronchial node taken from a 52-year-old male.
Deuterium Content of Peat as a Paleoclimatic Recorder
Authors: Schiegl W. E.
Published: October 2006

During the transformation of vegetable matter into peat the initial deuterium concentration decreases systematically with increasing carbon content. From this relationship the original deuterium content of the plants that formed the peat in Dutch peat bogs can be derived, and the values obtained can be correlated with past summer temperatures in the Netherlands.
Procollagen: Conversion of the Precursor to Collagen by a Neutral Protease
Authors: Bornstein Paul , Ehrlich H. Paul , Wyke Anne W.
Published: October 2006

An enzymatic activity (procollagen peptidase), capable of converting the biosynthetic precursor procollagen to collagen at neutral
p
H, has been identified in rat and chick calvarial bone. Limited proteolysis of procollagen with chymotrypsin resulted in a similar transformation. The activity in bone can be demonstrated in vitro despite inhibition of new collagen synthesis by cycloheximide. Preservation of the collagen precursor in preparations extracted with acetic acid results from inhibition of the enzymatic activity at low
p
H.
Externally Suppressible Proline Quadruplet CCC
U
⋅
Authors: Yourno Joseph , Kohno Tadahiko
Published: October 2006

Three (+1) frameshift mutations located at different genetic sites respond with high specificity to the same external suppressor. In each case, the suppressor restores small amounts of protein that is normal in electrophoretic mobility and heat stability. One of these proteins has been shown to have the wildtype amino acid sequence. The messenger RNA quadruplet CCC
U
⋅
appears to be common to all three frameshift sites and to be translated by the suppressor as proline. A likely suppressor agent is a proline transfer RNA with a quadruplet anticodon or its functional equivalent.
Lack of Enhanced Oxygen Consumption by Polymorphonuclear Leukocytes on Phagocytosis of Virulent
Salmonella typhi
Authors: Miller Roger M. , Garbus Joel , Hornick Richard B.
Published: October 2006

Human polymorphonuclear leukocytes exhibit an enhanced rate of oxygen consumption during phagocytosis of relatively avirulent strains of
Salmonella typhi
or
Staphylococcus aureus
. However, phagocytosis of a virulent strain of
Salmonella typhi
is not associated with augmented oxygen consumption. The ability of a bacterial strain to alter the postphagocytic rate of oxygen consumption of polymorphonuclear leukocytes may be related to its in vivo virulence.
Thyroxine-Binding Globulin: Characterization of the Binding Site with a Fluorescent Dye as a Probe
Authors: Green Allan M. , Marshall James S. , Pensky Jack , Stanbury John B.
Published: October 2006

The fluorescent dye 1,8-anilinonaphthalenesulfonate competed with thyroxine for binding to thyroxine-binding globulin. Fluorescence analysis indicated that the dye bound to the globulin in a molar ratio of 1:1 and with an association constant (at 23°C) of 4.19 × 10
6
M
-1
, and that thyroxine bound to the globulin in a molar ratio of 1:1 and with an association constant (at 23°C) of 2.35 × 10
10
M
-1
. Displacement of globulin-bound dye by thyroxine was shown by fluorescence quenching, and displacement of globulin-bound thyroxine by dye was demonstrated by ultrafiltration.
Ratite Eggshells from Lanzarote, Canary Islands
Authors: Franz Sauer E. G. , Rothe Peter
Published: October 2006

Struthious and aepyornithoid eggshells from Tertiary calcareous sediments on Lanzarote prove the presence, until about 12 million years ago, of large flightless birds. The calcarenite horizon is recognized as an old land surface. Mesozoic sedimentary rocks in the basement of the volcanic islands of Lanzarote and neighboring Fuerteventura indicate that at least part of the Canary Archipelago is underlain by continental crust. Separation of the eastern Canaries from Africa might have been by rifting, and a land connection might still have existed in the lower Pliocene.
Motion Perception: A Color-Contingent Aftereffect
Authors: Favreau Olga Eizner , Emerson Victor F. , Corballis Michael C.
Published: October 2006

When observers who watched repeated alternations of a red contracting spiral and a green expanding spiral were later shown stationary spirals, red and green, the red stationary spiral appeared to be expanding and the green stationary spiral appeared to be contracting. These color-contingent motion aftereffects complement reports of motion-contingent color aftereffects and suggest that both may reflect adaptation of detectors specific to color and motion.
Leukemia, Lymphoma, and Osteosarcoma Induced in the Syrian Golden Hamster by Simian Virus 40
Authors: Diamandopoulos George Th.
Published: October 2006

Leukemia, lymphoma, and osteogenic and anaplastic sarcomas develop in Syrian golden hamsters inoculated intravenously at 3 weeks of age with simian virus 40, which is a popova virus. Previously, only RNA and herpes DNA viruses have been recognized as capable of inducing leukemia and lymphoma in mammals. The significance of these findings is emphasized in relation to the nature of viral agents that may be involved in analogous diseases of man.
Mars: The Lineament Systems
Authors: Binder Alan B. , McCarthy Donald W.
Published: October 2006

Analysis of the Mariner 4, Mariner 6, and Mariner 7 photographs shows that Mars has at least two distinct types of lineament systems. The most prominent is a well-developed global-type system. The second consists of radial and concentric lineaments associated with the Hellas and south polar basins.
Barrier Dune System along the Outer Banks of North Carolina: A Reappraisal
Authors: Dolan Robert
Published: October 2006

Barrier dune development has been encouraged by man along the Outer Banks of North Carolina to stabilize the barrier islands. This modification of a delicately balanced natural system is leading to severe adjustments in both geological and ecological processes.
Delayed Fertilization and Chromosome Anomalies in the Hamster Embryo
Authors: Yamamoto Masaharu , Ingalls Theodore H.
Published: October 2006

Polyploidy and aneuploidy in hamster embryos are produced as manifestations of pregnancy wastage in surviving young when the interval between the estimated time of ovulation and copulation and hence fertilization is progressively increased. Significant delays resulted in triploidy in runted embryos, and the sporadic occurrence of mosaic aneuploidies.
Methadone Binding to Human Plasma Albumin
Authors: Olsen George D.
Published: October 2006

The interaction ofL-[1-3H] methadone with human plasma albumin was studied by equilibrium dialysis. The percent of methadone bound to albumin was relatively independent of the concentration of methadone, but was dependent on the concentration of albumin, ranging from 8.0 to 43.8 percent bound as the albumin concentration increased from 0.400 gram to 5.00 grams per 100 milliliters of solution.
Splitbrain Monkeys: Cerebral Control of Ipsilateral and Contralateral Arm, Hand, and Finger Movements
Authors: Brinkman J. , Kuypers H. G. J. M.
Published: October 2006

The connections of the descending pathways in the monkey suggest that each hemisphere controls independent arm, hand, and finger movements contralaterally, but mainly arm movements ipsilaterally. This difference could be observed in splitbrain monkeys executing a visuomotor task with one eye covered, provided tactile guidance of the movements was largely prevented.
Wavelength Effect on Visual Latency
Authors: Weingarten Franklin S.
Published: October 2006

Chromatic stimuli were matched in luminance to a homogeneous white background field. The relative visual latency, as measured by subjective simultaneity, of 621-nanometer (red) light was 20 to 25 milliseconds less than that for 549-nanometer (green) light. When the chromatic stimuli were different in luminance from the background field, no differences in visual latency related to the wavelength of light were observed. The procedure of matching the luminance of test fields to that of a background field appears to be crucial for observing a visual latency difference related to wavelength.
Viral and Cellular DNA Polymerase: Comparison of Activities with Synthetic and Natural RNA Templates
Authors: Robert Marjorie S. , Smith R. Graham , Gallo Robert C. , Sarin Prem S. , Abrell John W.
Published: October 2006

Two DNA polymerases purified from normal human lymphocytes are distinguishable from the viral reverse transcriptases of avian myeloblastosis virus and Mason-Pfizer monkey virus by their relative affinity for select templates. In this respect, the activity of the two normal human lymphocyte polymerases closely resembles the activity of
Escherichia coli
DNA polymerase 1. The viral and cellular DNA polymerases are equally active with the nonspecific template, poly(rA) ⋅ poly(dT). Criteria for distinguishing the activity of viral reverse transcriptase are discussed.
Capture Resonance of the Asteroid 1685 Toro by the Earth
Authors: Danielsson L. , Ip W.-H
Published: October 2006

The asteroid 1685 Toro has its perihelion inside the Earth's orbit and a period which is 8/5 of that of the Earth. A calculation of Toro's orbit covering 200 years shows that this asteroid at present is captured in resonance with the Earth. The capture is due to the gravitational interaction at close encounters between the bodies.
L-α-Methyl-β-hydrazino-β-(3,4-dihydroxyphenyl)propionic Acid: Relative Lack of Antidecarboxylase Activity in Adrenals
Authors: Horita A. , Nair X. , Hamilton A. E.
Published: October 2006

In rats previously treated with a monoamine oxidase inhibitor, the administration of 5-hydroxytryptophan results in increases in concentrations of 5-hydroxytryptamine in kidney, brain, and adrenal glands. When the peripheral L-aromatic amino acid decarboxylase inhibitor, L-α-methyl-α-hydrazino-β-(3,4-dihydroxyphenyl) propionic acid (HMD) is administered prior to 5-hydroxytryptophan, the concentration of 5-hydroxytryptamine in kidneys does not rise, that of the brain increases slightly, and that of the adrenal rises markedly. This indicates that although the adrenal gland is a peripheral organ, it does not respond in the typical manner to the antidecarboxylase action of HMD. These results suggest that HMD does not gain free access into the adrenal medulla and that a possible "blood-adrenal barrier" may exist to this compound.
Lunar Crust: Structure and Composition
Authors: Toksöz M. N. , Press F. , Anderson K. , Dainty A. , Latham G. , Ewing M. , Dorman J. , Lammlein D. , Sutton G. , Duennebier F. , Nakamura Y.
Published: October 2006

Lunar seismic data from artificial impacts recorded at three Apollo seismometers are interpreted to determine the structure of the moon's interior to a depth of about 100 kilometers. In the Fra Mauro region of Oceanus Procellarum, the moon has a layered crust 65 kilometers thick. The seismic velocities in the upper 25 kilometers are consistent with those in lunar basalts. Between 25 and 65 kilometers, the nearly constant velocity (6.8 kilometers per second) corresponds to velocities in gabbroic and anorthositic rocks. The apparent velocity is high (about 9 kilometers per second) in the lunar mantle immediately below the crust.
Chilean Glacial Chronology 20,000 to 11,000 Carbon-14 Years Ago: Some Global Comparisons
Authors: Mercer J. H.
Published: October 2006

Chilean glaciers at a latitude of 41°S reached a maximum extent about 19,400 carbon-14 years before the present (B. P.), shrank 50 percent by 16,000 years B. P., and readvanced to a smaller maximum after 14,800 years B. P. These fluctuations were closely in step with those of the Laurentide ice sheet east of the Mississippi River but differ somewhat from the accepted sequence in New Zealand. A corresponding pattern is not apparent in the Antarctic paleotemperature curve deduced from changes in oxygen isotope ratios.
Adaptation in Retinal Rods of Axolotl: Intracellular Recordings
Authors: Grabowski S. R. , Pinto L. H. , Pak W. L.
Published: October 2006

Intracellular recordings of the late receptor potential from rods of isolated axolotl retinas revealed the existence of a dark adaptation mechanism that is independent of rod pigment regeneration. Response amplitude of individual rods was measured as a function of intensity both before and at various times after exposure to bleaching illumination. The rod sensitivity increased by at least 3 to 4 log units during a period of 15 to 25 minutes following the bleach. During this time rod pigment regeneration was either too small to be measured or was nonexistent in our preparation.
5,6-
trans
-25-Hydroxycholecalciferol: Vitamin D Analog Effective on Intestine of Anephric Rats
Authors: Holick M. F. , Garabedian M. , DeLuca H. F.
Published: October 2006

A new compound, 5,6-trans-25-hydroxycholecalciferol, has been synthesized and tested for its biological activity. Like 1,25-dihydroxycholecalciferol, it stimulates intestinal calcium transport in anephric rats, whereas 25-hydroxycholecalciferol does not. But this analog has little if any activity in stimulating mobilization of calcium from the bone of anephric rats.
Rod-Cone Interactions: Different Color Sensations from Identical Stimuli
Authors: McCann John J.
Published: October 2006

Different color sensations were generated by two areas in a complex scene, even though both areas sent to the eye the same 656-nanometer radiance that excited the long-wave cones and the same 546-nanometer radiance that excited only the rods.
Autosensitization of Lymphocytes against Thymus Reticulum Cells
Authors: Cohen Irun R. , Wekerle Hartmut
Published: October 2006

Lymph nodes of normal rats contain lymphocytes that can be induced in vitro to mediate a specific cellular immune reaction against reticulum cells derived from syngeneic adult thymus glands. It is likely that these lymphocytes had access to reticulum cell antigens during the period in which they developed immunocompetence within the thymus. This suggests that contact with self-antigens during development may not eliminate self-reactive lymphocytes. These findings are in conflict with the theory that natural tolerance to self-antigens depends upon elimination of lymphocyte clones.
Dielectrophoresis of Macromolecules: Determination of the Diffusion Constant of Poly-γ-Benzyl-L-Glutamate
Authors: Eisenstadt Maurice , Scheinberg I. Herbert
Published: October 2006

The translational diffusion constant of poly-γ-benzyl-L-glutamate in ethylene dichloride was measured by dielectrophoresis. The method is rapid, precise to about ± 5 percent, and yields values in good agreement with those obtained by standard methods.
Biosynthesis of Hemoglobin Ann Arbor: Evidence for Catabolic and Feedback Regulation
Authors: Adams J. G. , Winter W. P. , Rucknagel D. L. , Spencer H. H.
Published: October 2006

Hemoglobin Ann Arbor, in which arginine replaces leucine in position 80 of the α chain, occurs in affected individuals in low proportion to hemoglobin A. Biosynthetic studies were performed on reticulocytes of a patient heterozygous for this hemoglobin. These studies suggested that the low percentage of hemoglobin Ann Arbor is primarily due to preferential destruction of the abnormal component. The reduced concentration of α Ann Arbor chains was also reflected in a decreased synthesis of normal β chains.
Linkage of Faulty Major Histocompatibility Complex Class I to Autoimmune Diabetes
Authors: Faustman Denise , Li Xiangping , Lin Herbert Y. , Fu Yineng , Eisenbarth George , Avruch Joseph , Guo Jane
Published: October 2006

Pancreatic islet cells are the targets of an autoimmune response in type I diabetes. In the nonobese diabetic (NOD) mouse model of autoimmune diabetes, expression of major histocompatibility complex (MHC) class I proteins was inversely correlated with diabetes; in this mouse a mutation in the MHC class II-linked gene for the putative MHC class I peptide transporter was also present. Mice deficient in MHC class I expression because they do not produce β
2
-microglobulin also developed late onset autoimmune diabetes. In cells from humans with type I diabetes expression of MHC class I was decreased; subsets of prediabetics categorized as most likely to become hyperglycemic also had low MHC class I. T cell responses to self antigens are faulty in diabetics. In sets of genetically identical twins that are discordant for diabetes, the defect appeared to reside with the antigen presenting cell. Thus, a lack of surface MHC class I protein is associated with autoimmune diabetes; the concomitant defect in antigen presentation may impair the development of self tolerance, which could result in autoimmune disease.
Human Glyceraldehyde-3-Phosphate Dehydrogenase in Man-Rodent Somatic Cell Hybrids
Authors: Bruns Gail A. P. , Gerald Park S.
Published: October 2006

The human enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) forms heteropolymers with the rodent enzyme in man-rodent somatic cell hybrids. A gene specifying GAPDH is syntenic with the genes specifying the glycolytic enzymes triosephosphate isomerase (TPI) and lactate dehydrogenase B (LDH-B). The synteny of GAPDH, TPI, and LDH-B is the first evidence for the syntenic association of human genes that specify enzymes of the Embden-Meyerhof glycolytic pathway.
A Binding Protein for Fatty Acids in Cytosol of Intestinal Mucosa, Liver, Myocardium, and Other Tissues
Authors: Ockner Robert K. , Manning Joan A. , Poppenhausen Ruth B. , Ho William K. L.
Published: October 2006

A protein of molecular weight ∼ 12,000 which binds long-chain fatty acids and certain other lipids has been identified in cytosol of intestinal mucosa, liver, myocardium, adipose tissue, and kidney. Binding is noncovalent and is greater for unsaturated than for saturated and medium-chain fatty acids. This protein appears to be identical with the smaller of two previously described cytoplasmic anion-binding proteins. Binding of long-chain fatty acids by this protein is greater than that of other anions tested, including sulfobromophthalein, and does not depend on negative charge alone. The presence of this binding protein may explain previously observed differences in intestinal absorption among fatty acids, and the protein may participate in the utilization of long-chain fatty acids by many mammalian tissues.
Neural Attenuation of Responses to Emitted Sounds in Echolocating Bats
Authors: Suga Nobuo , Schlegel Peter
Published: October 2006

Bats of the family Vespertilionidae emit strong ultrasonic pulses for echolocation. If such sounds directly stimulate their ears, the detection of echoes from short distances would be impaired. The responses of lateral lemniscal neurons to emitted sounds were found to be much smaller than those to playback sounds, even when the response of the auditory nerve was the same to both types of sounds. Thus, responses to self-vocalized sounds were attenuated between the cochlear nerve and the inferior colliculus. The mean attenuation was 25 decibels. This neural attenuating mechanism is probably a part of the mechanisms for effective echo detection.
Rare-Earth Oxides of Manganese and Cobalt Rival Platinum for the Treatment of Carbon Monoxide in Auto Exhaust
Authors: Voorhoeve R. J. H. , Remeika J. P. , Freeland P. E. , Matthias B. T.
Published: October 2006

The perovskite-like compounds RE

1-
x

Pb

x

MnO
3
and RECoO
3
, where RE (rare earth) is lanthanum, praseodymium, or neodymium, are active catalysts for the oxidation of carbon monoxide. Crushed single crystals of these compounds compare favorably with commercial platinum catalysts in initial activity and lifetime. Therefore, these compounds are promising substitutes for platinum in devices for the catalytic treatment of auto exhaust.
Systemic Absorption of Intrauterine Copper
Authors: Okereke Tati , Sternlieb Irmin , Morell Anatol G. , Scheinberg I. Herbert
Published: October 2006

A comparison of the various effects, in rats, of intrauterine insertion of copper-64 or copper-67 wire with the effects of intraperitoneal injection of copper sulfate solutions has shown that copper ions, dissolved from the wire, are locally active contraceptively and, in part, systemically absorbed.
Atmospheric Sulfur: Its Effect on the Chemical Weathering of New England
Authors: Johnson Noye M. , Reynolds Robert C. , Likens Gene E.
Published: October 2006

The present acidity and sulfur content of the upland streams of New England can be accounted for on the basis of the rainout and washout of sulfuric acid from the atmosphere. In spite of this excess acid flux over the New England landscape, the rate of cationic denudation of upland watersheds is relatively low.
World Dynamics: A Note
Authors: Boyd Robert
Published: October 2006

The results of Forrester's world model are shown to be very sensitive to changes in assumptions.
Aryl Hydrocarbon (Benzopyrene) Hydroxylase Is Stimulated in Human Lymphocytes by Mitogens and Benz[
a
]anthracene
Authors: Whitlock James P. , Cooper Herbert L. , Gelboin Harry V.
Published: October 2006

A mixed-function oxidase that requires reduced nicotinamide adenine dinucleotide phosphate, is carbon monoxide sensitive, and is drug-metabolizing is present in human lymphocytes and is increased to different levels by treatment with phytohemagglutinin, pokeweed mitogen, and a polycyclic hydrocarbon.
Mouse Leukemia: Depression of Serum Interferon Production
Authors: De Maeyer-Guignard Jaqueline
Published: October 2006

Production of circulating interferon is significantly impaired in AKR/J mice after development of lymphoblastic leukemia and in Balb/c mice with clinical signs of Friend erythroblastic leukemia. This alteration has been observed with three interferon inducers, each one known to elicit an interferon response in different cells.
Social Control of Sex Reversal in a Coral-Reef Fish
Authors: Robertson D. R.
Published: October 2006

Males of
Labroides dimidiatus
control the process of sex reversal within social groups. Each group consists of a male with a harem of females, among which larger individuals dominate smaller ones. The male in each harem suppresses the tendency of the females to change sex by actively dominating them. Death of the male releases this suppression and the dominant female of the harem changes sex immediately. Possible genetic advantages of the system are considered.
Detection of Molecular Oxygen on Mars
Authors: Carleton N. P. , Traub W. A.
Published: October 2006

Molecular oxygen was detected in martian spectra near 7635 angstroms and its abundance measured both during and after the 1971 dust storm. Its column abundance in the clear martian atmosphere is about 10.4 ± 1.0 centimeters amagat, giving a mixing ratio of molecular oxygen to carbon dioxide of 1.3 × 10-
3
. The mixing ratio of molecular oxygen to carbon monoxide (1.4 ± 0.3) is quite different from the value of 0.5 that would result from the photolysis of a pure carbon dioxide atmosphere, which indicates that there is or was a net source of oxygen relative to carbon (probably water) in the martian atmosphere.
RNA Metabolism in Tracheal Epithelium: Alteration in Hamsters Deficient in Vitamin A
Authors: Kaufman David G. , Baker Mary S. , Smith Joseph M. , Henderson William R. , Harris Curtis C. , Sporn Michael B. , Saffiotti Umberto
Published: October 2006

The electrophoretic pattern of RNA molecules that are synthesized in vitro in tracheal epithelium from hamsters deficient in vitamin A differs from that of RNA synthesized in normal, pair-fed control hamsters. There is less RNA of low electrophoretic mobility in the epithelial cells deficient in vitamin A. This alteration is reversed after the deficient animals have been treated with vitamin A.
Variation in Tyrosine Aminotransferase Induction in HTC Cell Clones
Authors: Aviv Dvora , Thompson E. Brad
Published: October 2006

Examination of tyrosine aminotransferase induction in many HTC cell subclones revealed a wide and unstable distribution of inducibility. The instability of this phenotype cannot easily be explained by classical mutation rates. These observations may be important in interpreting certain cell fusion experiments.
Cell Culture on Artificial Capillaries: An Approach to Tissue Growth in vitro
Authors: Knazek Richard A. , Gullino Pietro M. , Kohler Peter O. , Dedrick Robert L.
Published: October 2006

Artificial capillaries perfused with culture medium provide a matrix in which cells can attain tissue-like densities in vitro. Products secreted into the medium can be measured as indicators of cell function or may be recovered for other purposes without disturbing the culture.
Lead Content of Human Hair (1871-1971)
Authors: Weiss D. , Whitten B. , Leddy D.
Published: October 2006

Samples of antique and contemporary human hair were analyzed for lead by atomic absorption spectroscopy. Antique hair contained a significantly greater amount of lead than did contemporary hair.
Ridge Transform Fault Spreading Pattern in Freezing Wax
Authors: Oldenburg Douglas W. , Brune James N.
Published: October 2006

A laboratory experiment shows that ridge-ridge transform faults, inactive fracture zones, and other features characteristic of spreading oceanic ridges can be produced in a variety of paraffins. Although the resultant pattern depends upon the temperature of the wax and the ratio of spreading rate to surface cooling, the characteristic orthogonal ridge transform fault system is a preferred mode of separation. Symmetric spreading occurs under conditions of no tensile strength across the ridge, and the stability of transform faults is a consequence of their lack of shear strength. The experiment also shows that properties characteristic of oceanic ridges occur under conditions of passive convection where upwelling of material at the ridge crest is a result only of hydrostatic forces in the fluid; that is, the plate separation is caused not by large convective forces beneath the ridge but rather by tensile forces in the plate.
Aryl Hydrocarbon Hydroxylase Induction in Human Leukocytes
Authors: Busbee D. L. , Shaw C. R. , Cantrell E. T.
Published: October 2006

A method for determining aryl hydrocarbon hydroxylase induction in human leukocytes is described. Leukocytes from healthy volunteers were cultured in the presence of phytohemagglutinin, a mitogen. Addition of 3-methylcholanthrene to 72-hour cultures induced a fourfold increase in aryl hydroxylase activity. In the absence of a mitogenic agent, 3-methylcholanthrene stimulation of increased enzymatic activity did not occur.
Hypothalamic Norepinephrine: Circadian Rhythms and the Control of Feeding Behavior
Authors: Margules D. L. , Lewis Michael J. , Dragovich James A. , Margules Adrienne S.
Published: October 2006

The time of day is a decisive determinant of the effects of
l-
norepinephrine on feeding behavior. During the dark, direct application of
l-
norepinephrine to the hypothalamus of rats suppressed feeding behavior. During the light, treatment with the same dose of
l-
norepinephrine facilitated feeding behavior. Thus,
l-
norepinephrine has dual and opposite effects on feeding behavior. A hypothalamic substrate that fluctuates in a circadian rhythm could account for both actions of
l-
norepinephrine.
Orbit-Orbit Resonance Capture in the Solar System
Authors: Greenberg R. J. , Counselman C. C. , Shapiro I. I.
Published: October 2006

A realistic model involving mutual gravitation and tidal dissipation for the first time provides a detailed explanation for satellite orbit-orbit resonance capture. Although applying directly only to Saturn's satellites Titan and Hyperion, the model reveals general principles of resonance capture, evolution, and stability which seem applicable to other orbit-orbit resonances in the solar system.
Ionic Basis of the Photoresponse of
Aplysia
Giant Neuron: K
+
Permeability Increase
Authors: Brown H. Mack , Brown Arthur M.
Published: October 2006

The giant neuron of the
Aplysia
abdominal ganglion hyperpolarizes during illumination. The light-initiated potential change is associated with an increase of membrane conductance. It reverses sign at the potassium equilibrium potential
(
about -83 millivolts
),
which was determined from direct measurements of internal potassium activity. The membrane hyperpolarization is produced entirely by a light-induced increase in potassium permeability.
Transfer Factor: Delayed Hypersensitivity to
Schistosoma mansoni
and Tuberculin in
Macaca mulatta
Authors: Maddison Shirley E. , Hicklin Martin D. , Conway Brian P. , Kagan Irving G.
Published: October 2006

Delayed hypersensitivity in
Macaca mulatta
infected with either
Schistosoma mansoni
or mycobacteria was demonstrated by biopsies of skin test sites. Both dialyzable and nondialyzable leukocyte extracts from infected donors transferred delayed hypersensitivity to recipient monkeys. In two recipients, skin test conversion was associated with in vitro transformation of the recipients' lymphocytes.
Chimpanzee Bipedalism: Cineradiographic Analysis and Implications for the Evolution of Gait
Authors: Jenkins Farish A.
Published: October 2006

Bipedal chimpanzees reorient the pelvis to achieve an upright posture but retain the same pattern of femoral flexion and extension as in quadrupedal walking. Major differences from human gait are the abducted, relatively more flexed excursion of the femur and the timing of pelvic tilt, which raises during the swing phase. The femoral head morphology in the fossil hominid
Australopithecus robustus
is evidence of an approximately vertical excursion of the femur in contrast to the adducted pattern of modern man and the abducted pattern of chimpanzees.
Antigens Specific for Human Lymphocytic and Myeloid Leukemia Cells: Detection by Nonhuman Primate Antiserums
Authors: Metzgar Richard S. , Mohanakumar T. , Miller Donald S.
Published: October 2006

Primate antiserums to human leukemia cells can detect antigens specific for lymphocytic leukemia cells or antigens present on certain myeloid leukemia cells. The antigen specific for lymphocytic leukemia cells is destroyed by treatment with neuraminidase or trypsin. Tryptic digests of lymphocytic leukemia cells contain the antigen, which has a high molecular weight.
Crystal Structure of Krypton Difluoride at -80°C
Authors: Burbank R. D. , Falconer W. E. , Sunder W. A.
Published: October 2006

Krypton difluoride is tetragonal, space group
P
4
2
/
mnm
, with two linear molecules per unit cell aligned in planes perpendicular to the tetrad axes. The alignment alternates by 90 degrees between successive planes. The krypton-fluorine bond distance is 1.89 ± 0.02 angstroms.
Habituation and Dishabituation: Interactions between Peripheral and Central Nervous Systems in
Aplysia
Authors: Lukowiak Kenneth , Jacklet Jon W.
Published: October 2006

The withdrawal response of the isolated siphon of
Aplysia
habituates to a light stimulus and dishabituates to a tactile stimulus, and vice versa, with or without connections to the central nervous system. The peripheral nervous system can dishabituate or enhance the response mediated by the central nervous system and vice versa. Normally the adaptive siphon withdrawal response of the intact animal must be mediated by the integrated activity of the peripheral and central nervous systems.
Is a Scanning Ion Microscope Feasible?
Authors: Martin F. W.
Published: October 2006

Atomic collisions of high-energy heavy ions produce large yields of x-rays. The small de Broglie wavelength of massive ions leads to an estimate of 0.2 angstrom for the resolution of a microscope utilizing nitrogen ions with energies of 14 million electron volts. Estimates of the yield of x-rays relative to molecular radiation damage of the bases in DNA are made.
Image of a Sulfur Atom
Authors: Ottensmeyer F. P. , Schmidt E. E. , Olbrecht A. J.
Published: October 2006

Two-dimensional signal averaging has been applied to dark field electron micrographs of molecules of 2,3,4,5-tetraacetoxymercurithiophene. Only the mercury atom images are seen in single micrographs. However, in the composite image, resulting from photographic superposition of 64 individual images, the sulfur atom in the molecule is clearly revealed.
Upper Pleistocene Radiocarbon-Dated Artefacts from the Northern Yukon
Authors: Irving W. N. , Harington C. R.
Published: October 2006

The evidence presented here indicates that man lived in the eastern part of the Beringian refugium before the peak of the late Wisconsin glaciation. He had sharp, stone tools intended for working bone and means of breaking large mammoth bones. Probably he hunted mammoth and caribou, and prepared the skins of the caribou for use as clothing and perhaps shelter. It is possible that he migrated to southern North America, although evidence for the presence of man there prior to the peak of the Wisconsin glaciation is at present in dispute. We do not know whether his culture should be classified as Mousteroid or Aurignacoid in Müller-Beck's scheme, whose criteria are taken from stone implements of which we have none, although we infer their presence. Our data suggest that in Beringia, and therefore probably in Siberia and the Far East, the transition from Middle Paleolithic to Upper Paleolithic levels of technology occurred at a relatively early date. This raises the larger question: Did the transition from Middle to Upper Paleolithic occur simultaneously in many parts of the world, or did it begin in and spread from one area?
Red Sea Drillings
Authors: Ross David A. , Whitmarsh Robert B. , Ali Syed A. , Boudreaux Joseph E. , Coleman Robert , Fleisher Robert L. , Girdler Ronald , Manheim Frank , Matter Albert , Nigrini Catherine , Stoffers Peter , Supko Peter R.
Published: October 2006

Recent drilling in the Red Sea has shown that much of the basin is underlain by evaporites of a similar age to that of evaporites found in the Mediterranean Sea. These evaporites and their structural positions indicate that other brine areas are present—and, indeed, several others have been discovered.
Immunoglobulin A: Site and Sequence of Expression in Developing Chicks
Authors: Kincade P. W. , Cooper M. D.
Published: October 2006

Synthesis of immunoglobulins A, G, and M (IgA, IgG, and IgM) is prevented in chickens by embryonic treatment with heterologous antibodies to IgM when combined with bursectomy at hatching. Cells that produce IgA are seeded from the bursa of Fabricius later than cells capable of IgM and IgG synthesis; the latter do not convert to IgA synthesis outside of the bursa.
Lower
p
H Limit for the Existence of Blue-Green Algae: Evolutionary and Ecological Implications
Authors: Brock Thomas D.
Published: October 2006

Observations on a wide variety of acidic environments, both natural and man-made, reveal that blue-green algae (Cyanophyta) are completely absent from habitats in which the
p
H is less than 4 or 5, whereas eukaryotic algae flourish. By using enrichment cultures with inocula from habitats of various
p
H values, the absence of blue-green algae at low
p
H was confirmed
Hyaluronates: Relation between Molecular Conformations
Authors: Atkins Edward D. T. , Sheehan John K.
Published: October 2006

The discovery that both potassium and sodium salts of hyaluronic acid can exist in a double-strand helical conformation that will convert to the already known single-strand helical structures illustrates the remarkable conformational versatility of this biopolymer. X-ray diffraction was used to monitor variations in molecular conformation as a function of several independent, controllable variables, such as relative humidity, temperature, and applied tension. A scheme is presented for the interrelation of a range of hyaluronate conformations.
DNA Complementary to Ribosomal RNA: Relation between Genomic Proportion and Ploidy
Authors: Siegel Albert , Lightfoot Donald , Ward Oscar G. , Keener Sherry
Published: October 2006

Ten
Nicotiana
species were assayed for the proportion of DNA that is complementary to ribosomal RNA. This proportion varies from 0.27 to 0.9 percent, with tetraploid species having lower values than the diploid species. The tetraploid species have about twice as much DNA per cell as do diploid species. Thus, the absolute number of genes for ribosomal RNA varies less than the proportion of complementary DNA. Further, the number of genes for the RNA in 80
S
ribosomes varies less among species than does that for the RNA in 70
S
ribosomes. The data indicate that loss of DNA complementary to ribosomal RNA is associated with tetraploidy in the genus
Nicotiana
.
Lunar Surface Radioactivity: Preliminary Results of the Apollo 15 and Apollo 16 Gamma-Ray Spectrometer Experiments
Authors: Metzger A. E. , Trombka J. I. , Peterson L. E. , Reedy R. C. , Arnold J. R.
Published: October 2006

Gamma-ray spectrometers on the Apollo 15 and Apollo 16 missions have been used to map the moon's radioactivity over 20 percent of its surface. The highest levels of natural radioactivity are found in Mare Imbrium and Oceanus Procellarum with contrastingly lower enhancements in the eastern maria. The ratio of potassium to uranium is higher on the far side than on the near side, although it is everywhere lower than commonly found on the earth.
Coal Mine Explosions: Seasonal Trends
Authors: Kissell Fred N. , Nagel Allan E. , Zabetakis Michael G.
Published: October 2006

An analysis of disaster reports on coal mine explosions indicates that gas explosions are randomly distributed throughout the year, whereas dust explosions (which may or may not be triggered by a gas explosion) occur with greater frequency during the dry fall and winter months. The lack of adequate moisture during cold weather tends to increase the rate and severity of the dust explosions.
Phenylketonuria: Phenylalanine Inhibits Brain Pyruvate Kinase in vivo
Authors: Miller A. L. , Hawkins R. A. , Veech R. L.
Published: October 2006

The hypothesis that brain damage in phenylketonuria is related to inhibition of pyruvate kinase by phenylalanine was examined in rat brain in vivo. One hour after a single injection of phenylalanine into the rat, the brains were removed and completely frozen in less than a second. The concentration of phenylalanine in the brain was comparable to that found in phenylketonuric patients. Changes in brain glycolytic intermediates were consistent with inhibition of pyruvate kinase in vivo. The inhibition of pyruvate kinase was apparently compensated for by an increase in phosphoenolpyruvate; no decrease in adenosine triphosphate or creatine phosphate was found.
Propagation of Environmental Noise
Authors: Lyon R. H.
Published: October 2006

Although the basic processes associated with the propagation of environmental noise, such as reflection, scattering, and spreading are well known, numerous theoretical problems remain. The propagation processes that are significant in different situations have yet to be identified, and criteria for evaluating their relative importance in each situation must be developed. In evaluating the noise of aircraft, for example, attenuation caused by the spreading of energy may exceed 60 dB, with atmospheric attenuation accounting for another 10 dB or so. In the propagation of highway noise, on the other hand, spreading may account for only 10 dB of attenuation, air absorption for 1 dB, and absorption by ground may account for 10 to 15 dB of attenuation. If those problems are approached systematically, we should be able to predict accurately the effects of noise sources and barriers and thus control the distribution of noise levels in cities and suburban areas.
Menkes' Kinky Hair Disease: Further Definition of the Defect in Copper Transport
Authors: Danks D. M. , Cartwright Elizabeth , Stevens B. J. , Townley R. R. W.
Published: October 2006

Duodenal mucosa obtained from two patients with Menkes' syndrome contained abnormally large amounts of copper. The defect in copper absorption in this disease must lie in the process of intracellular handling or of transport across the serosal cell membrane. Fibroblastic cells cultured from the skin of patients and of heterozygous females show intense metachromasia in primary culture which disappears in subculture. These cells may be useful for the study of copper transport in vitro and for the identification of heterozygotes in affected families.
Fossil Lepidopterous Leaf Mines Demonstrate the Age of Some Insect-Plant Relationships
Authors: Opler Paul A.
Published: October 2006

The discovery of impressions of 11 kinds of lepidopterous leaf mines, together with a reevaluation of previous reports, contributes significantly to the fossil record for that insect order. It is also concluded that some specific insect-plant associations have persisted from the Miocene to the present.
Rare-Earth Manganites: Catalysts with Low Ammonia Yield in the Reduction of Nitrogen Oxides
Authors: Voorhoeve R. J. H. , Remeika J. P. , Johnson D. W.
Published: October 2006

Rare-earth manganites such as La

1-
x

Pb

x

MnO
3
, with 0.3 < x < 0.6, and their perovskite-like homologs are active catalysts for the reduction of nitric oxide to molecular nitrogen. At low temperatures, innocuous nitrous oxide rather than ammonia is the main side product. The activity of single crystalline catalysts and of ceramic catalysts of this type is substantially improved by etching with dilute acids.
Megagauss Physics
Authors: Fowler C. M.
Published: October 2006

Fields greater than 10 MG can be produced by explosive flux compression and fields up to 3 MG with capacitor banks. Measurement of fields up to 10 MG is reliable, but difficulties may be expected at higher fields. Megagauss fields have been applied successfully as high-pressure sources, in high-energy particle physics, and in solid-state investigations. Other uses remain to be exploited: plasma compression by megagauss fields has been relatively unsuccessful but shows promise; their use as particle accelerators has been studied only theoretically; and much work remains to be done, both experimentally and theoretically, in connection with applications of megagauss fields in solidstate physics.

Note added in proof:
Since this article was prepared, Grigor'ev
et al.
have carried out some experiments in which they have compressed hydrogen up to a density of 1.95 grams per cubic centimeter with a calculated pressure of 8 × 10
6
atmospheres. They report five different pressure-density points and claim that their data can be explained by assuming that the transition to the metallic phase occurs at a pressure of 2.8 × 10
6
atmospheres, with a density change from 1.08 to 1.3 g/cm
3
. Using the flux compression techniques described earlier in this article, Hawke
et al.
have obtained a pressure-density point at 1.5 × 10
6
atmospheres and 1.0 g/cm
3
, which is also not inconsistent with a predicted equation of state of metallic hydrogen. In view of the experimental uncertainties, none of the pressure-density data can yet be used conclusively to establish the transition's existence. Hawke and his co-workers are presently engaged in measurements of the electrical conductivity of the compressed hydrogen. Observation of a significant conductivity at the proposed transition pressure would be a more definitive test of a metallic transition. In addition, two lower pressure-density points have been obtained for deuterium by the Los Alamos group, by means of the flux compression methods described earlier in this article. One point agrees to within experimental error with a slight extrapolation of Stewart's data. The second point is at a pressure of 65 ± 3 × 10
3
atmospheres with a density of 0.71 ± 0.10 g/cm
3
. The data are tentative, and efforts are under way to obtain more data points at both higher and lower pressures.
Octopamine-Sensitive Adenylate Cyclase: Evidence for a Biological Role of Octopamine in Nervous Tissue
Authors: Nathanson James A. , Greengard Paul
Published: October 2006

An adenylate cyclase that is activated specifically by very low concentrations of octopamine has been identified both in homogenates and in intact cells of the thoracic ganglia of an insect nervous system. This enzyme appears to be distinct from two other adenylate cyclases present in the same tissue, which are activated by dopamine and by 5-hydroxytryptamine, respectively. The data raise the possibility of a role of octopamine-sensitive adenylate cyclase in the physiology of synaptic transmission.
Earthquake Prediction: Variation of Seismic Velocities before the San Francisco Earthquake
Authors: Whitcomb James H. , Garmany Jan D. , Anderson Don L.
Published: October 2006

A large precursory change in seismic body-wave velocities occurred before the earthquake in San Fernando, California. The discovery that this change is mainly in the
P
-wave velocity clearly relates the effect to the phenomenon of dilatancy in fluid-filled rocks. This interpretation is supported by the time-volume relation obtained by combining the present data with the data from previous studies. The duration of the precursor period is proportional to the square of an effective fault dimension, which indicates that a diffusive or fluid-flow phenomenon controls the time interval between the initiation of dilatancy and the return to a fully saturated condition which is required for rupture.
Obsidian Hydration Dates Glacial Loading?
Authors: Friedman Irving , Pierce Kenneth L. , Obradovich John D. , Long William D.
Published: October 2006

Three different groups of hydration rinds have been measured on thin sections of obsidian from Obsidian Cliff, Yellowstone National Park, Wyoming. The average thickness of the thickest (oldest) group of hydration rinds is 16.3 micrometers and can be related to the original emplacement of the flow 176,000 years ago (potassium-argon age). In addition to these original surfaces, most thin sections show cracks and surfaces which have average hydration rind thicknesses of 14.5 and 7.9 micrometers. These later two hydration rinds compare closely in thickness with those on obsidian pebbles in the Bull Lake and Pinedale terminal moraines in the West Yellowstone Basin, which are 14 to 15 and 7 to 8 micrometers thick, respectively. The later cracks are thought to have been formed by glacial loading during the Bull Lake and Pinedale glaciations, when an estimated 800 meters of ice covered the Obsidian Cliff flow.
Early Hominid Humerus from East Rudolf, Kenya
Authors: McHenry H. M.
Published: October 2006

A fossil hominid humerus discovered in 1970 by the expedition to East Rudolf, Kenya, led by R. E. F. Leakey is examined in comparison with a large series of extant hominoids. This comparison as well as a multiple discriminant analysis shows the uniqueness of the fossil among the hominoids.
Thyrotropin and Cyclic Nucleotide Effects on Prostaglandin Levels in Isolated Thyroid Cells
Authors: Burke Gerald , Chang Lin-Lin , Szabo Marta
Published: October 2006

Thyrotropin increases prostaglandin levels in isolated thyroid cells. Since comparable results were obtained with butyrated cyclic adenosine monophosphate derivatives as well as with the phosphodiesterase inhibitors quazodine and theophylline, it appears that cyclic adenosine monophosphate mediates this effect of thyrotropin. These observations suggest that intracellular prostaglandins play a role in modulating thyrotropin action on thyroid.
Osteopetrosis Cured by Temporary Parabiosis
Authors: Walker Donald G.
Published: October 2006

The excessive accumulations of spongiosa in the long bones of congenitally osteopetrotic mice permanently disappeared after a brief parabiotic union to normal littermates. Most of the bone removal was accomplished long after interruption of parabiosis. It is proposed that, during parabiosis, progenitors of competent osteolytic cells were recruited from the blood of the normal mouse.
Ice Nucleation: Elemental Identification of Particles in Snow Crystals
Authors: Parungo Farn P. , Pueschel Rudolf F.
Published: October 2006

A scanning field-emission electron microscope combined with an x-ray analyzer is used to locate the ice nucleus within a three-dimensional image of a snow crystal and determine the chemical composition of the nucleus. This makes it possible to better understand the effect of nuclei in cloud seeding.