bluuebunny/crossref_metadata_2025 huggingface dataset:
Modulation of Adenylate Cyclase Activity in Liver and Fat Cell Membranes by Insulin
Authors: Illiano Gennaro , Cuatrecasas Pedro
Published: October 2006

Insulin depresses both the activity of adenylate cyclase stimulated by glucagon, epinephrine, and sodium fluoride in liver cell membranes and the activity of adenylate cyclase stimulated by epinephrine and adrenocorticotropin in particulate preparations from homogenates of isolated fat cells. Significant inhibition is detected with very low concentrations (10
-11
molar) of insulin but not with unphysiologically high (> 10
-9
molar) concentrations of the hormone. These direct effects of insulin on an enzymatic system in broken-cell preparations suggest a fundamental role of adenylate cyclase activity and of cyclic adenosine monophosphate in the mechanism of action of insulin.
Twins: Early Mental Development
Authors: Wilson Ronald S.
Published: October 2006

Mental development was appraised periodically for infant twins, and the twins displayed high within-pair concordance for level of mental development during the first and second years. Twins were also concordant for the spurts and lags in development in this period (monozygotic twins more so than dizygotic). From these results it was inferred that infant mental development was primarily determined by the twins' genetic blueprint and that, except in unusual cases, other factors served mainly a supportive function.
Pancreatic Beta-Cell Web: Its Possible Role in Insulin Secretion
Authors: Orci L. , Gabbay K. H. , Malaisse W. J.
Published: October 2006

A cortical band of fine microfilaments is consistently observed in the beta cells of the rat pancreas. Alteration of this cell web by cytochalasin B is associated with an enhancement of glucose-induced secretion of insulin by isolated islets. The microfilamentous web of the beta cell may play an important role in the emiocytosis of insulin secretory granules, by controlling their access to the cell membrane.
White-Noise Analysis of a Neuron Chain: An Application of the Wiener Theory
Authors: Marmarelis Panos Z. , Naka Ken-Ichi
Published: October 2006

The Wiener theory of nonlinear system identification was applied to a three-stage neuron chain in the catfish retina in order to determine the functional relationship between the artificial polarization of the horizontal cell membrane potential and the resulting discharge of the ganglion cell. A mathematical model was obtained that can predict quantitatively, with reasonable accuracy, the nonlinear, dynamic behavior of the neuron chain. The applicability of the method is discussed. We conclude that this is a very powerful method in the analysis of information transfer in the central nervous system.
Amino Acid Composition of Planktonic Foraminifera: A Paleobiochemical Approach to Evolution
Authors: King Kenneth , Hare P. E.
Published: October 2006

A unique, species-specific amino acid composition is identified with each of 16 species of planktonic Foraminifera isolated from the tops of deep-sea sediment cores. This amino acid pattern appears to directly reflect the genotype. The total amino acid content ranges from 2.0 to 4.2 micromoles per gram of calcified tissue or 0.02 to 0.04 percent by weight. Analyses of two Early Miocene species indicate that characteristic compositional differences are sufficiently well preserved over geologic time to determine phylogenetic affinities among extinct species living at least 18 million years ago.
High-Temperature Superconductors, the First Ternary System
Authors: Matthias B. T. , Marezio M. , Corenzwit E. , Cooper A. S. , Barz H. E.
Published: October 2006

A new system of high-temperature superconductors is reported. The compounds, Mo

6 -
x

A

x

S
6
where A is Cu, Zn, Mg, Ag, Cd, Sn, or Pb, are rhombohedral with α ≃ 6.5 angstroms and ∼ 90°. The transition temperatures range from ∼ 2.5°K for the Cd compound to ∼ 13°K for the Pb compound.
Cochlear Microphonic Audiograms in the "Pure Tone" Bat
Chilonycteris parnellii parnellii
Authors: Pollak George , Henson O. W. , Novick Alvin
Published: October 2006

Audiograms are sharply tuned to a frequency close to the second harmonic of the pulse. The tuning, which is much sharper than previously reported for any vertebrate receptor, provides a mechanism whereby the bat can effectively perceive echoes even during periods of pulse-echo overlap.
Multivariate Analysis of an Early Hominid Metacarpal from Swartkrans
Authors: Rightmire G. P.
Published: October 2006

Discriminant analysis permits hand bones of living primate genera to be represented as swarms of points in a multidimensional statistical framework within which intergroup relationships, and the affinities of fossil forms, can be examined. The metacarpal of
Paranthropus
from Swartkrans, South Africa, was so located with respect to groups of monkeys, apes, and modern man. The results suggest that the fossil metacarpal may be functionally similar to that of chimpanzees.
Acetylcholine Receptors: Number and Distribution at Neuromuscular Junctions in Rat Diaphragm
Authors: Fambrough Douglas M. , Hartzell H. Criss
Published: October 2006

The number of acetylcholine receptors per motor end plate in the rat diaphragm, measured by the binding of [
125
I]α-bungarotoxin, varies directly with rat size and is (4.0 ± 0.2) × 10
7
for full-grown male rats. Autoradiographic analysis of single fibers labeled with this substance reveals that virtually all of these receptors are localized in the end plate.
Ergot-Induced Inhibition of Pituitary Tumor Growth in Rats
Authors: Quadri S. K. , Lu K. H. , Meites J.
Published: October 2006

Daily injections of ergocornine or ergonovine, for 3 weeks, into rats carrying a prolactin- and growth hormone-secreting pituitary tumor (MtW15) induced significant regression or inhibition of tumor growth, whereas ergocryptine had no significant effect. Ergocornine caused a decrease in cells and a disappearance or pycnosis of nuclei in the tumor tissue, and a reduced concentration of prolactin in blood.
Receptor-Estrogen Complex in the Nuclear Fraction of Rat Uterine Cells during the Estrous Cycle
Authors: Clark J. H. , Anderson J. , Peck E. J.
Published: October 2006

A quantitative method was used to determine the concentration of receptor-estrogen complex in the nuclear fraction of rat uterine cells throughout the estrous cycle. The concentrations of nuclear receptor-estrogen complex were: metestrus, 0.22; diestrus, 0.75; proestrus, 1.29; and estrus, 0.31 picomoles per milligram of DNA. This cyclic fluctuation in the nuclear complex closely parallels the secretion of ovarian estrogen during the estrous cycle, an indication that the accumulation of receptor-estrogen complex by the nuclear fraction of uterine cells may be of physiological significance, and under the control of endogenous estrogen.
Eye and Head Turning Indicates Cerebral Lateralization
Authors: Kinsbourne Marcel
Published: October 2006

When solving verbal problems, right-handed people usually turn head and eyes to the right, whereas with numerical and spatial problems, these people look up and left. Left-handed people differ in all these respects. The results suggest that the direction in which people look while thinking reflects the lateralization of the underlying cerebral activity.
Valinomycin Crystal Structure Determination by Direct Methods
Authors: Duax W. L. , Hauptman H. , Weeks C. M. , Norton D. A.
Published: October 2006

The conformation of an uncomplexed form of the antibiotic valinomycin (C
54
N
6
O
18
H
90
) has been determined by direct methods including a novel technique for strong enantiomorph discrimination via the calculation and systematic analysis of cosine invariants of a special type. The intramolecular hydrogen bonding scheme and the isopropyl group stereochemistry of uncomplexed valinomycin are compatible with interpretations of spectral measurements for the complexed and uncomplexed molecule in solution but are different from any previously proposed structure. The simple conformational change of a hydrogen bond shift, which could be induced by the process of potassium ion complexing, transforms the uncomplexed into the complexed structure.
Revegetation following Forest Cutting: Mechanisms for Return to Steady-State Nutrient Cycling
Authors: Marks P. L. , Bormann F. H.
Published: October 2006

Dense stands of a woody, successional species,
Prunus pensylvanica
L., develop rapidly, with early closure of canopy and rapid attainment of high values of net annual production and nutrient accumulation. Such rapid growth following disturbance tends to minimize losses of nutrients from the ecosystem, thus promoting a return to steady-state cycling characteristic of a mature forest.
Effects on Humans of Δ
9
-Tetrahydrocannabinol Administered by Smoking
Authors: Galanter Marc , Wyatt Richard J. , Lemberger Louis , Weingartner Herbert , Vaughan Tom B. , Roth Walton T.
Published: October 2006

Twelve chronic marijuana users received Δ
9
-tetrahydrocannabinol by smoking. The magnitude of their pulse increment was highly correlated with their subjective experiences. Three of the 12 subjects subsequently received Δ
9
-tetrahydrocannabinol labeled with carbon-14; the time course of its concentration in plasma was highly correlated with the pulse increment. Subjective symptoms, however, appeared later and dissipated more slowly.
Natural Selection for Müllerian Mimicry in
Heliconius erato
in Costa Rica
Authors: Benson Woodruff W.
Published: October 2006

The natural color pattern of individuals of the unpalatable and mimetic butterfly
Heliconius erato
was altered to a unique nonmimetic pattern. When returned to natural populations, the nonmimetic individuals remained for shorter periods of time and received more wing damage indicative of predator attacks than did the controls. The results indicate that Müllerian mimicry was functioning to protect the butterflies from predation.
Genetic and Immunological Complexity of Major Histocompatibility Regions
Authors: Bach Fritz H. , Widmer Michael B. , Segall Miriam , Bach Marilyn L. , Klein Jan
Published: October 2006

There are genetic differences within the major histocompatibility complex of the mouse which lead to skin graft rejection but which cannot be detected serologically. When confronted with these differences on allogeneic cells, lymphocytes proliferate in vitro. In other cases, in vitro lymphocyte proliferation but no skin graft rejection is associated with loci that are linked to but genetically separable from the loci controlling the serologically defined antigens.
Gratings Mask Bars and Bars Mask Gratings: Visual Frequency Response to Aperiodic Stimuli
Authors: Weisstein Naomi , Bisaha John
Published: October 2006

Gratings and bars produce unexpected mutual visual masking. A grating masks a bar much less than a bar masks a bar; and a bar masks a grating uniformly over the grating field. These effects suggest that neural populations selective for size and orientation may be involved in frequency analysis rather than in simple feature detection.
Target-Set and Response-Set Interaction: Implications for Models of Human Information Processing
Authors: Egeth Howard , Marcus Norman , Bevan William
Published: October 2006

In binary character-classification tasks, reaction time generally has been reported to increase substantially with the number of target elements. However, when the targets formed a familiar set and subjects were not required to make explicit "no" responses, reaction time did not increase significantly as the target set increased in size from one to three.
Inhibition of Rap1A Binding to Cytochrome b
558
of NADPH Oxidase by Phosphorylation of Rap1A
Authors: Bokoch Gary M. , Quilliam Lawrence A. , Bohl Benjamin P. , Jesaitis Algirdas J. , Quinn Mark T.
Published: October 2006

Rap1A is a low molecular weight guanosine triphosphate (GTP)-binding protein in human neutrophil membranes whose cellular function is unknown. Rap1A was found to form stoichiometric complexes with the cytochrome b
558
component of the phagocyte nicotinamide adenine dinucleotide phosphate (NADPH) oxidase system. The (guanosine-5′-
O
-(3-thiotriphosphate) (GTP-γ-S)-bound form of Rap1A bound more tightly to cytochrome b
558
than did the guanosine diphosphate-bound form. No complex formation was observed between cytochrome b
558
and H-Ras-GTP-γ-S or Rap1A-GTP-γ-S that had been heat-inactivated, nor between Rap1A-GTP-γ-S and hydrophobic proteins serving as controls. Complex formation between Rap1A-GTP-γ-S and cytochrome b
558
was inhibited by phosphorylation of Rap1A with cyclic adenosine monophosphate (cAMP)-dependent protein kinase. These observations suggest that Rap1A may participate in the structure or regulation of the NADPH oxidase system and that this function of the Rap1A protein may be altered by phosphorylation.
Perceiving Real-World Scenes
Authors: Biederman Irving
Published: October 2006

When a briefly presented real-world scene was jumbled, the accuracy of identifying a single, cued object was less than that when the scene was coherent. Jumbling remained an effective variable even when the subject knew where to look and what to look for. Thus an object's meaningful context may affect the course of perceptual recognition and not just peripheral scanning or memory.
Increased Tolerance of Leukemic Mice to Arabinosyl Cytosine with Schedule Adjusted to Circadian System
Authors: Haus Erhard , Halberg Franz , Scheving Lawrence E. , Pauly John E. , Cardoso Sergio , Kühl Jürgen F. W. , Sothern Robert B. , Shiotsuka Ronald N. , Hwang Dar Shong
Published: October 2006

Mice (BDF
1
) inoculated with L1210 leukemia survive for a statistically significantly longer span when four courses of arabinosyl cytosine are administered at 4-day intervals-not in courses consisting of eight equal doses at 3-hour intervals, but in sinusoidally increasing and decreasing 24-hour courses, the largest amount being given at previously mapped circadian and circannual times of peak host resistance to the drug. This finding relates to the many therapeutic situations involving rhythmic, and thus predictable, cycles in the host's tolerance of undesired effects from the agent used.
Accretionary Processes in the Early Solar System: An Experimental Approach
Authors: Kerridge John F. , Vedder James F.
Published: October 2006

Micrometer-size silicate flakes do not accrete during impacts in the velocity range 1.5 to 9.5 kilometers per second. Conventional accretionary theories for silicate bodies are applicable only to particles whose orbits are similar. Metal-silicate fractionation in the solar system may have been affected by differences in the accretionary behavior of the metal and silicate particles.
Genetics of the Antibody Response to Dextran in Mice
Authors: Blomberg Bonnie , Geckeler William R. , Weigert Martin
Published: October 2006

The immune response to dextran having the α-1,3 linkage may be under the control of antibody structural genes. Mice that respond well to this antigen produce antibody restricted with respect to light chain class (λ) and to an antigenic determinant resulting from a particular heavy and light chain interaction. The response to dextran is controlled by a locus linked to the heavy chain locus.
Kom Ombo: Preliminary Report on the Fauna of Late Paleolithic Sites in Upper Egypt
Authors: Churcher C. S. , Smith P. E. L.
Published: October 2006

A Late Pleistocene fauna comprising 3 fish, 1 reptile, 22 birds, and 14 mammals is identified from sites containing Sebilian, Sebekian, Silsilian, Menchian, and Halfan industries. It is remarkable for its variety, especially of birds, and gives evidence for year-round occupation of these sites.
Evolutionary Clock: Nonconstancy of Rate in Different Species
Authors: Jukes Thomas H. , Holmquist Richard
Published: October 2006

By using various methods for comparing polypeptide sequences we find that the evolutionary divergence of rattlesnake cytochrome c from cytochromes c of species in other classes has been more rapid than that of cytochrome c of another reptile, the snapping turtle. This suggests that the evolutionary rate of change of cytochromes c is species-dependent as well as time-dependent.
Evidence for Parathyroid Failure in Magnesium Deficiency
Authors: Anast Constantine S. , Mohs James M. , Kaplan Sheldon L. , Burns Thomas W.
Published: October 2006

Serum immunoreactive parathyroid hormone (IPTH) was low to nondetectable in spite of hypocalcemia in a patient with chronic magnesium deficiency. The administration of magnesium led to parallel increases in serum IPTH, serum calcium, and renal phosphate clearance. These findings support the view that magnesium depletion may result in impaired synthesis or release of parathyroid hormone in man, or both.
Nicotine Blocks the Suckling-Induced Rise in Circulating Prolactin in Lactating Rats
Authors: Blake Charles A. , Sawyer Charles H.
Published: October 2006

In lactating rats the rapid suckling-induced release of pituitary prolactin into circulating blood is inhibited by a subcutaneous injection of nicotine. This treatment does not block the lesser "stress-induced" rise in prolactin in response to either. Although nicotine may impair milk production by its effect on prolactin release, it does not appear to block milk ejection from the lactating mammary gland.
Chromatic Specificity of the Visual Evoked Response
Authors: Perry N. W. , Childers D. G. , Falgout J. C.
Published: October 2006

The temporal alternation of red and green stripes in a structured field produces successive contrast, which can elicit cortical potentials recorded from the scalp. Amplitudes of the major frequency components of the potentials correspond to the relative intensities of red and green producing the contrast. The amplitude variations are color-specific, since total luminance and structure are held constant.
Coordinated Development of β-Glucuronidase and β-Galactosidase in Mouse Organs
Authors: Meisler Miriam , Paigen Kenneth
Published: October 2006

Changing concentrations of β-glucuronidase and β-galactosidase are coordinated during the development of mouse liver, heart, and brain. Although coordinate, the developmental patterns for the two enzymes are under independent control by genetic elements apparently linked to the respective structural genes.
Inhibition of Angiotensin Conversion in Experimental Renovascular Hypertension
Authors: Miller Edward D. , Samuels Alan I. , Haber Edgar , Barger A. Clifford
Published: October 2006

Constriction of the renal artery and controlled reduction of renal perfusion pressure is followed by a prompt increase in systemic renin activity and a concomitant rise in blood pressure in trained, unanesthetized dogs. The elevated blood pressure induced by the renal artery stenosis can be prevented by prior treatment with the nonapeptide Pyr-Trp-Pro-Arg-Pro-Gln-Ile-Pro-Pro, which blocks conversion of angiotensin I to angiotensin II. Further, the nonapeptide can restore systemic pressure to normal in the early phase of renovascular hypertension. These results offer strong evidence that the renin-angiotensin system is responsible for the initiation of hypertension in the unilaterally nephrectomized dog with renal artery constriction.
Relation between REM Sleep and Intracranial Self-Stimulation
Authors: Steiner Solomon S. , Ellman Steven J.
Published: October 2006

Depriving rats of rapid eye movement (REM) sleep was shown to lower their thresholds and raise their response rates for rewarding brain stimulation. Conversely, allowing rats to self-stimulate while they were being deprived of this sleep form reduced the amount of REM rebound during recovery from deprivation. These results demonstrate a reciprocal relation between rewarding brain stimulation and REM sleep.
Human Prolactin: 24-Hour Pattern with Increased Release during Sleep
Authors: Sassin J. F. , Frantz A. G. , Weitzman E. D. , Kapen S.
Published: October 2006

Human prolactin was measured in plasma by radioimmunoassay at 20-minute intervals for a 24-hour period in each of six normal adults, whose sleep-wake cycles were monitored polygraphically. A marked diurnal variation in plasma concentrations was demonstrated, with highest values during sleep; periods of episodic release occurred throughout the 24 hours.
Cracks and Pores: A Closer Look
Authors: Brace W. F. , Silver E. , Hadley K. , Goetze C.
Published: October 2006

Most pores and some cracks in several rocks, as directly viewed with a new technique, have a shape that suggests an origin early in the history of these rocks. Thus, behavior in the laboratory may be a reliable indication of behavior in the earth's crust, for electrical resistivity, permeability, or other properties that depend on microporosity.
Precision Geodesy via Radio Interferometry
Authors: Hinteregger H. F. , Shapiro I. I. , Robertson D. S. , Knight C. A. , Ergas R. A. , Whitney A. R. , Rogers A. E. E. , Moran J. M. , Clark T. A. , Burke B. F.
Published: October 2006

Very-long-baseline interferometry experiments, involving observations of extragalactic
radio sources, were performed in 1969 to determine the vector separations between antenna
sites in Massachusetts and West Virginia. The 845.130-kilometer baseline was estimated
from two separate experiments. The results agreed with each other to within 2 meters in
all three components and with a special geodetic survey to within 2 meters in length; the
differences in baseline direction as determined by the survey and by interferometry
corresponded to discrepancies of about 5 meters. The experiments also yielded positions
for nine extragalactic radio sources, most to within 1 arc second, and allowed the
hydrogen maser clocks at the two sites to be synchronized a posteriori with an uncertainty
of only a few nanoseconds.
Genetic Mapping of a Murine Leukemia Virus-Inducing Locus of AKR Mice
Authors: Rowe Wallace P. , Hartley Janet W. , Bremner Theodore
Published: October 2006

The chromosomal location of one of the two murine leukemia virus-inducing loci of AKR mice has been determined. The locus, which appears to be the integrated genome of the virus, is designated
Akv-1
, and is on linkage group I, 12 map units from
Gpi-1
, with gene order
c-Gpi-1-Akv-1
. This identification of a closely linked gene whose phenotype is independent of virus expression should facilitate analysis of the biologic importance of the
Akv-1
locus.
Synaptic Transmission at Single Glomeruli in the Turtle Cerebellum
Authors: Walsh J. V. , Houk J. C. , Atluri R. L. , Mugnaini E.
Published: October 2006

We have recorded from the granular layer of the turtle cerebellum extracellular unitary potentials that appear to reflect pre- and postsynaptic events at the synapse between a single swelling of a mossy fiber and the dendritic tips of several granule cells. The presynaptic component is an all-or-none potential. It can be directly activated by spinal stimulation and is unaltered by repetitive activity or by high concentrations of magnesium. The postsynaptic component is a graded potential. It follows the presynaptic component by approximately 1 millisecond and is depressed by repetitive activity and by high concentrations of magnesium. The recording of large potentials produced by the flow of postsynaptic current within a single glomerulus suggests powerful transmission. Electron micrographs demonstrate large cerebellar glomeruli in the turtle and a substantial accumulation of mitochondria in the dendritic tips of granule cells.
University-Industry Interaction Patterns
Authors: Roy Rustum
Published: October 2006

The nation is entering a period when the R & D output must be increased, probably without major increases in resource allocation. Obviously, in this situation, either efficiency or productivity must be increased. Perhaps one of the most wasteful aspects of the national R & D system (and one that received little attention during the golden era of the 15 percent per year expansion) has been the very weak coupling between the university, on the one hand, and industry (or government), on the other. It is a serious error to allege about such coupling that "it has never worked," that the objectives and reward structures of the institutions are such that it cannot work, and so on. The fact is that coupling has never been tried seriously. History shows that the total dollar effort in research that
required
coupling or that had coupling as its main objective was on the order of $10 million per year (that is, much less than 0.1 percent of the research money spent on U.S. campuses). At the same time, there is little doubt that the experiments which must and will be tried in the immediate future call for innovations in management and changes in the attitude and structure of many universities. In conversations with administrators who have had experience with such programs, I have found strong suggestions of very mixed responses from the universities. In light of these responses, and if effectiveness is a goal, it would be better for those universities that are more wedded to disciplinary research, to single principal-investigator work,
not
to participate in these new efforts. We need much greater diversity in the styles of university life, and it would be healthy for the academic enterprise if some universities retained a greater degree of detachment from society, while others consciously decided to interact more with it, through the private sector, and made the changes necessary to do so. If initial funding is restricted to those universities that consider university-industry or university-government research a worthy objective and that have a proven track record and a favorable administrative and reward structure, the new programs may well establish a major new pattern of national R & D.
Ceramidase Deficiency in Farber's Disease (Lipogranulomatosis)
Authors: Sugita Mutsumi , Dulaney John T. , Moser Hugo W.
Published: October 2006

Ceramidase activity could not be demonstrated in the kidney and cerebellum from a deceased patient with Farber's disease, whereas the activities of six control acid hydrolase enzymes appeared normal. This enzyme defect presumably accounts for the accumulation that has been described in two patients and may represent the biochemical basis of this disorder.
Object Distance as a Determinant of Visual Fixation in Early Infancy
Authors: McKenzie B. E. , Day R. H.
Published: October 2006

Data from two experiments show that the duration of visual fixation of solid objects by infants aged 6 to 20 weeks varies as a function of object distance between 30 and 90 centimeters. There was no characteristic habituation of fixation of an object at 90 centimeters but there was a marked increase in fixation time when objects were advanced to 30 centimeters (experiment 1). A linear decline in fixation times occurred as the object distance increased from 30 to 90 centimeters with the real size and the angular size of the object held constant (experiment 2). No evidence for visual size constancy in young infants was obtained by this method.
Observational Learning and Social Facilitation in the Rat
Authors: Zentall Thomas R. , Levine John M.
Published: October 2006

Learning by rats was facilitated when response-relevant cues were provided by other rats; learning increased as a function of number of cues provided. These results suggest that rats can learn by imitation. Learning by rats that observed conspecifics not emitting response-relevant cues was retarded compared to learning by rats that did not observe conspecifics. This indicates that a conspecific's presence can also inhibit learning, a result consistent with social facilitation theory.
Unisexual Fish: Laboratory Synthesis of a "Species"
Authors: Schultz R. Jack
Published: October 2006

By hybridizing bisexual (gonochoristic) fishes, all-female clones have been produced that are comparable to those of a wild unisexual "species,"
Poeciliopsis monacha-lucida
, living in northwestern Mexico. The laboratory unisexuals have consistently given birth only to female progeny for six generations.
Running on Two or on Four Legs: Which Consumes More Energy?
Authors: Taylor C. Richard , Rowntree V. J.
Published: October 2006

Disagreement exists over whether man's bipedal form of locomotion evolved as an economical means for covering long distances. There is also some disagreement about the energetic price man had to pay to free his hands. In an investigation of the relative energetic cost of bipedal and quadrupedal locomotion in primates, chimpanzees (
Pan troglodytes
) and capuchin monkeys (
Cebus capucinus
) were trained to run on a treadmill either on two or on four legs while their oxygen consumption was being measured. Both primates expend the same amount of energy whether running on two or on four legs. The relative energy cost of bipedal versus quadrupedal running should not be used in arguments about the evolution of bipedal locomotion in man.
Gene Flow and Population Differentiation
Authors: Endler John A.
Published: October 2006

There are many possible spatial patterns of selection and gene flow that can produce a given cline structure; the actual geography of natural selection and gene flow must be worked out before an attempt is made to explain a given natural cline in terms of a model.

The results of experimental and theoretical models show that it is possible for local differentiation to evolve parapatrically in spite of considerable gene flow if the selection gradients are relatively uniform. Irregularities in environmental gradients increase the sensitivity of clines to the effects of gene flow in proportion to the increase in the differences in gene frequencies between the emigrants and the demes receiving the immigrants. It is not necessary for a sharp spatial environmental change to be present for distinct differentiation to occur. In some cases even a gentle environmental gradient can give rise to marked spatial differentiation along a genetically continuous series of demes; such environmental differences may be below the practical limits of resolution in field studies. Any asymmetry in gene flow does not lead to dedifferentiation if the environmental gradient is smooth; it merely shifts the position of the transition zone between the differentiated areas from that which would be expected if there were no asymmetry. Abrupt geographic differences in gene, genotype, or morph frequencies should not, therefore, be interpreted as evidence for environmental changes in the immediate vicinity of the steepest part of the cline; neither should they be interpreted as evidence for geographic barriers, sharp environmental differences, or sexual isolation among the differentiated groups of populations when there are no other sources of evidence for these phenomena. Gene flow may be unimportant in the differentiation of populations along environmental gradients.
The Hydroperoxyl Radical in Atmospheric Chemical Dynamics: Reaction with Carbon Monoxide
Authors: Davis D. D. , Payne W. A. , Stief L. J.
Published: October 2006

From measurements of the photochemical rate of production of CO
2
16,18
and CO
2
16,16
, produced from the low intensity photolysis of mixtures of CO, H
2
O, Ar, and O
2
18,18
, the rate constant for the reaction HO
2
+ CO → CO
2
+ OH has been determined at 300°K to be less than or equal to 10
-20
cubic centimeter per molecule per second. These measurements indicate that the reaction of thermalized HO
2
is of negligible importance as a sink mechanism for converting CO to CO
2
in either the troposphere or the stratosphere.
Leaching: Use of a Thermophilic and Chemoautotrophic Microbe
Authors: Brierley Corale L. , Murr L. E.
Published: October 2006

A chemoautotrophic, thermophilic, and acidophilic microorganism capable of oxidizing reduced sulfur and iron compounds and leaching concentrates of molybdenite and chalcopyrite at 60°C has been characterized by transmission and scanning electron microscopy. This constitutes the first direct observations of microorganisms on ore fines.
Synthesis of Reverse Osmosis Membranes by Plasma Polymerization of Allylamine
Authors: Hollahan John R. , Wydeven Theodore
Published: October 2006

The polymerization of allylamine in a radio-frequency electrodeless plasma to form thin polymer films on microporous filter media provides very effective dry composite membranes for reverse osmosis. Salt and urea rejections as high as 98 percent and 46 percent, respectively, have been achieved from a solution containing 10 grams of sodium chloride per liter and 10 grams of urea per liter. The plasma conditions and polymerization technique are discussed.
Adenosine 3′,5′-Monophosphate in Pancreatic Islets: Glucose-Induced Insulin Release
Authors: Charles M. Arthur , Fanska R. , Schmid Florence G. , Forsham Peter H. , Grodsky Gerold M.
Published: October 2006

Glucose-induced release of insulin from perifused rat islets is associated with elevated islet adenosine 3′,5′-monophosphate. If values for adenosine 3′,5′-monophosphate are compared to insulin release during theophylline or glucose stimulation and theophylline plus glucose stimulation, it suggests a minor role for adenosine 3′,5′-monophosphate in directly stimulating insulin release but a prominent role in modulating glucose-induced release of insulin.
Phosphorus Dynamics in Lake Water
Authors: Lean D. R. S.
Published: October 2006

An exchange mechanism exists in lake water between phosphate and plankton, but the excretion of an organic phosphorus compound by the plankton is also a significant process. It results in the extracellular formation of a colloidal substance, and most of the nonparticulate phosphorus in lake water is in this form.
Hepatic Drug Metabolism in Rats: Impairment in a Dirty Environment
Authors: Vesell Elliot S. , Lang C. Max , White William J. , Passananti G. Thomas , Tripp Spencer L.
Published: October 2006

Reduction of aniline hydroxylase activity, ethylmorphine
N
-dementhylase activity, and cytochrome P-450 content occurred in hepatic microsomes of rats kept under dirty conditions, defined as accumulation for 1 week of urine and feces in pans under the wire mesh cages. In comparison with rats that had urine and feces removed twice daily from such pans, rats kept over Kimpak bedding or over Litter Green, changed twice daily, also showed reduced drug-metabolizing activity in hepatic microsomes, but to a lesser degree than the dirty rats. Placement of a filter top on cages for 1 week also decreased drug-metabolizing activity. These experiments suggest that the relative cleanliness of an animal's environment can influence hepatic microsomal drug metabolism.
Angiotensin II: Important Role in the Maintenance of Arterial Blood Pressure
Authors: Johnson J. Alan , Davis James O.
Published: October 2006

An angiotensin II antagonist, [1-sarcosine, 8-alanine]-angiotensin II, was given intravenously to anesthetized dogs with thoracic caval constriction and ascites to investigate the role of angiotensin II in the control of arterial pressure. The antagonist produced a striking fall in arterial pressure and in aldosterone secretion and an accompanying increase in plasma renin activity. In a control experiment, normal anesthetized dogs were given the angiotensin analog, but it failed to reduce arterial pressure or to influence plasma renin activity. In conscious dogs with caval constriction, the antagonist produced essentially the same drop in arterial pressure as observed in anesthetized animals. These results suggest an important role for angiotensin II in the maintenance of arterial pressure by its action on specific receptor sites in arteriolar smooth muscle and in the adrenal cortex.
Trilobite Eyes: Calcified Lenses in vivo
Authors: Towe Kenneth M.
Published: October 2006

The corneal lenses preserved in the eyes of some of the Paleozoic trilobites (Arthropoda) are constructed of calcite that is crystallographically oriented to behave like glass. The calcareous lenses are capable of forming inverted images over a large depth of field and must have been present in the living trilobites.
Characterization of the Androgen Receptor from a Syrian Hamster Ductus Deferens Tumor Cell Line (DDT
1
)
Authors: Norris James S. , Kohler Peter O.
Published: October 2006

The hamster ductus deferens cloned tumor cell line (DDT
1
) contains a complex steroid receptor protein that binds
3
H-labeled 5 α-dihydrotestosterone. Diethylaminoethyl (DEAE) chromatography of cytosol from these cells yields two major receptor peaks of activity. Identification of this steroid binding protein as a cytoplasmic receptor was confirmed by salt dissociation on sucrose gradients, stability of the hormone-receptor complex at 0°C, and the retention patterns on phosphocellulose and DEAE cellulose. Multiple forms of the receptor exist in a single homogeneous cell type. The data support the theory that steroid hormones bind to a cytoplasmic protein receptor composed of dissimilar subunits as the initial step in steroid hormone action.
Enzyme Electrodes
Authors: Gough David A. , Andrade Joseph D.
Published: October 2006

From the discussion of electrodes and enzymes herein, and from the accounts of enzyme electrodes that have appeared in the literature, clinical determinations of certain metabolites and soluble enzymes by means of enzyme electrodes seem quite feasible. Such devices may be made highly specific by the use of appropriate enzymes and a high degree of accuracy can be obtained. Instantaneous and continuous determinations can be made from physiological fluids, and undesirable physiologic responses can theoretically be minimized, thus making long-term clinical monitoring a possibility. Enzyme electrodes may also have a useful lifetime and meet other practical requirements.
Volcanic Production Rates: Comparison of Oceanic Ridges, Islands, and the Columbia Plateau Basalts
Authors: Baksi A. K. , Watkins N. D.
Published: October 2006

New potassium-argon age data from the Columbia Plateau suggest a basalt production rate of 10
8
cubic meters per year during a middle Miocene volcanic episode. This is two to three times the production rate in some oceanic islands, and about four to six times the production rate in spreading mid-oceanic ridge systems.
Polychlorobiphenyls in North Atlantic Ocean Water
Authors: Harvey George R. , Steinhauer William G. , Teal John M.
Published: October 2006

Concentrations of polychlorobiphenyls (PCB's) have been measured at the surface and at various depths in the water of the North Atlantic Ocean between 26°N and 63°N. The concentrations average about 20 parts per trillion and amount to an estimated 2 × 10
4
metric tons of PCB's in the upper 200 meters of water. The average concentrations of PCB's in the surface water of the Sargasso Sea are lower than those in the northern North Atlantic.
Ferromagnetic Contamination in the Lungs and Other Organs of the Human Body
Authors: Cohen David
Published: October 2006

Contaminating particles which are ferromagnetic have been found in the human body. Their distribution was measured by applying an external magnetic field to the torso for a short time, and then, in a shielded room, mapping the steady magnetic field around the torso due to the magnetized particles. Maps of subjects show various distributions, including particles in the stomach from food cans and in the lungs from arc welding. The fields from these two sources are strong enough to be detected with a flux-gate magnetometer, without the need for a shielded room. This simplicity of detection of larger amounts of ferromagnetic contamination suggests that this method may be used in two applications: in detecting the presence of large amounts of asbestos (ferromagnetic and harmful) in the lungs of asbestos workers, and in tests of the condition of the lung where FE
3
O
4
dust (ferromagnetic and harmless) would be used as an inhaled tracer material.
Volatile Elements in Apollo 16 Samples: Possible Evidence for Outgassing of the Moon
Authors: Krähenbühl Urs , Ganapathy R. , Morgan John W. , Anders Edward
Published: October 2006

Several Apollo 16 breccias, including one containing goethite, are strikingly enriched in volatile elements such as bromine, cadmium, germanium, antimony, thallium, and zinc. Similar but smaller enrichments are found in all highland soils. It appears that volcanic processes took place in the lunar highlands, involving the release of volatiles including water. The lunar thallium/uranium ratio is 2 × 10
-4
of the cosmic ratio, which suggests that the moon's original water content could not have exceeded the equivalent of a layer 22 meters deep. The cataclastic anorthosites at the Apollo 16 site may represent deep ejecta from the Nectaris basin.
Ferroin-Collodion Membranes: Dynamic Concentration Patterns in Planar Membranes
Authors: DeSimone J. A. , Beil D. L. , Scriven L. E.
Published: October 2006

Patterns and waves of the Belousov-Zhabotinskii reaction are produced in membranes in which one reactant is immobilized. Convection is eliminated, the generation and deformation of wave forms are studied, and patterns are permanently fixed. Wave shape, frequency, length, and phase velocity are explained theoretically by the interactions of diffusion with reaction.
Horizontal Bands in the Belousov Reaction
Authors: Kopell N. , Howard L. N.
Published: October 2006

The formation and propagation of spatial patterns in the presence of an initial gradient in temperature or the concentration of one or more of the reactants is explained kinematically. Experimental verification of this mechanism is given, showing that diffusion plays a very minor role in the formation of the bands.
Angiotensin-Sodium Interaction in Blood Pressure Maintenance of Renal Hypertensive and Normotensive Rats
Authors: Gavras Haralambos , Brunner Hans R. , Vaughan E. Darracott , Laragh John H.
Published: October 2006

A specific inhibitor of angiotensin II was used in rats to investigate whether angiotensin is involved in the maintenance of blood pressure in one-kidney Goldblatt hypertension, in which plasma renin levels are not usually increased. The inhibitor produced marked falls in blood pressure, often down to normal levels in the hypertensive animals only when they were depleted in sodium and not after sodium repletion. Much lesser but still significant falls in blood pressure were also produced in normotensive sodium-depleted rats but not in repleted rats. We conclude that the importance of angiotensin for maintaining blood pressure is largely determined by its relation to available sodium or fluid volume, since the renin component in maintenance of either the hypertensive or the normotensive state could be exposed only by sodium deprivation. Therefore, volume expansion per se or other pressor factors may be involved in maintaining blood pressure of these sodium-replete normotensive or hypertensive animals.
Self-Stimulation Alters Human Sensory Brain Responses
Authors: Schafer Edward W. P. , Marcus Marilyn M.
Published: October 2006

Human electrocortical potentials evoked by self-administered auditory and visual stimuli manifest much smaller amplitude and faster poststimulus timing than do average brain responses evoked by identical machine-delivered stimuli. Auditory evoked potentials show this "self-stimulation effect" to a greater degree than do visual responses. For visual evoked potentials, the effect appears greater at the vertex association area than over the occipital cortex. Individual differences in the magnitude of the "self-stimulation effect" relate to level of intelligence.
Objective Assessment of Hypnotically Induced Time Distortion
Authors: Zimbardo Philip G. , Marshall Gary , White Greg , Maslach Christina
Published: October 2006

The objective precision of operant conditioning methodology validates the power of hypnosis to induce alterations in time perception. Personal tempo was systematically modified by instructions to trained hypnotic subjects, with significant behavioral effects observed on a variety of response rate measures.
Virus-Induced Cholesterol Crystals
Authors: Fabricant C. G. , Krook L. , Gillespie J. H.
Published: October 2006

One of the crystal types induced in cell cultures by a new feline herpesvirus was identified as cholesterol by crystal structure, polarized light microscopy, and mass spectroscopy.
12,13-Epoxy-Δ
9
-Trichothecenes as the Probable Mycotoxins Responsible for Stachybotryotoxicosis
Authors: Eppley Robert M. , Bailey William J.
Published: October 2006

Stachybotrys atra
cultures grown on oats produced five compounds toxic to brine shrimp; three are the sesquiterpenoid mycotoxins known as 12,13-epoxy-Δ
9
-trichothecenes. One trichothecene is roridin E, a known metabolite of
Myrothecium verrucaria
. The other two were hydrolyzed to verrucarol, the product of roridin and verrucarin hydrolysis. Spectroscopic data indicate that the two remaining compounds are also 12,13-epoxy-Δ
9
-trichothecenes. These metabolites are probably among those responsible for stachybotryotoxicosis.
An Atmosphere on Ganymede from Its Occultation of SAO 186800 on 7 June 1972
Authors: Carlson R. W. , Bhattacharyya J. C. , Smith B. A. , Johnson T. V. , Hidayat B. , Smith S. A. , Taylor G. E. , O'Leary B. , Brinkmann R. T.
Published: October 2006

On 7 June 1972 the third Jovian satellite Ganymede occulted the eighth-magnitude star SAO 186800. Successful photoelectric observations obtained at Lembang, Java (Indonesia), and Kavalur, India, show nonabrupt immersions and emersions, indicating the presence of an atmosphere whose surface pressure is greater than about 10
-3
millibar. By fitting the two occultation durations as chords to a model disk, the diameter is found to be 5270 (+30, -∼200) kilometers, the major error contribution arising from the uncertain atmospheric thickness below the occultation layer. The derived mean density is 2.0 (-0.03, + ∼0.2) grams per cubic centimeter.
Mammalian Cells in Culture Frequently Release Type C Viruses
Authors: Lieber M. M. , Benveniste R. E. , Livingston D. M. , Todaro G. J.
Published: October 2006

Cell cultures commonly used in animal cell research, both cell strains and continuous cell lines from various mammalian species, spontaneously produce type C RNA viruses.
Experimental Subacute Spongiform Virus Encephalopathies in Primates and Other Laboratory Animals
Authors: Gibbs Clarence J. , Gajdusek D. Carleton
Published: October 2006

The host range of subacute spongiform virus encephalopathies is described. The asymptomatic incubation period and the duration of the illnesses in various species of animal hosts is discussed along with information on additional species of Old World and New World monkeys and the domestic cat, which have been shown to be susceptible to subacute spongiform virus encephalopathies.
Complete Amino Acid Sequence of the Mu Heavy Chain of a Human IgM Immunoglobulin
Authors: Putnam F. W. , Florent G. , Paul C. , Shinoda T. , Shimizu A.
Published: October 2006

The amino acid sequence of the μ chain of a human IgM immunoglobulin, including the location of all disulfide bridges and oligosaccharides, has been determined. The homology of the constant regions of immunoglobulin μ, γ, α, and ε heavy chains reveals evolutionary relationships and suggests that two genes code for each heavy chain.
Proteins from Human Cerebrospinal Fluid: Binding with Nucleic Acids
Authors: Kubinski H. , Javid Manucher
Published: October 2006

Cerebrospinal fluid (CSF) contains two groups of proteins that bind tightly to DNA and to polyriboguanylic acid, respectively. In certain diseases the amounts of a given nucleic acid bound by a constant volume of CSF may increase, while in others the amount of such proteins may be reduced. Binding of polyriboguanylic acid increased in CSF samples from patients with brain tumors, stroke, multiple sclerosis, and communicating hydrocephalus, but it significantly decreased in CSF samples from patients with obstructive hydrocephalus. These increases may or may not be proportional to the rise in total CSF proteins characteristic for these diseases. Elevated binding of DNA was observed in samples from patients with hydrocephalus, epilepsy, and cortical atrophy. The technique described may be applicable to the diagnosis of a variety of diseases of the central nervous system.