bluuebunny/crossref_metadata_2025 huggingface dataset:
Aggression in Adult Mice: Modification by Neonatal Injections of Gonadal Hormones
Authors: Bronson F. H. , Desjardins Claude
Published: October 2006

Incidence of spontaneous aggression in adult male mice given a single injection of estradiol benzoate (0.4 milligram) when they were 3 days old was less than that of controls injected with oil. Aggressiveness was increased among adult females injected with either estradiol or testosterone propionate (1 milligram) at the same age. The increased aggressiveness noted among females given androgen was further documented during subsequent mating tests, when these females often attacked, wounded, and, in one case, killed naive males.
Herpes Simplex Virus in Mice: Electron Microscopy of Neural Spread
Authors: Rabin Erwin R. , Jenson A. Bennett , Melnick Joseph L.
Published: October 2006

Herpes simplex virus rapidly infected the trigeminal nerves of mice after intranasal inoculation. Centripetal neural spread was suggested by histologic evidence of encephalitis in the area of attachment of the trigeminal nerve. Furthermore, electron microscopy revealed virus replication primarily within Schwann cells of the trigeminal nerve, and neurons of the gasserian ganglion.
Sequential Translation of Trinucleotide Codons for the Initiation and Termination of Protein Synthesis
Authors: Caskey C. T. , Tompkins R. , Scolnick E. , Caryk T. , Nirenberg M.
Published: October 2006

Terminal events in protein synthesis were studied with trinucleotide codons. Initiator and terminator trinucleotides sequentially stimulate N-formyl-methionyl-tRNA binding to ribosomes and the release of free N-formyl-methionine from the ribosomal intermediate. The release factor discovered by Capecchi is also required. The trinucleotides UGA, UAA, and UAG were found to be terminator codons. This pattern of codon degeneracy has not been observed with other trinucleotides and transfer RNA.
Amyloidosis Induced in Mice by
Escherichia coli
Endotoxin
Authors: Barth Werner F. , Gordon Joyce K. , Willerson James T.
Published: October 2006

Amyloidosis was produced in mice by repeated subcutaneous injections of 0.5- or 0.005-milligram amounts of
Escherichia coli
endotoxin. Of the two strains of mice examined, amyloidosis was induced more readily in one than in the other. The ability of endotoxin to induce amyloidosis lends support to the view that stimulation of reticuloendothelial cells leads to amyloid formation.
Estradiol-Concentrating Neurons: Topography in the Hypothalamus by Dry-Mount Autoradiography
Authors: Stumpf Walter E.
Published: October 2006

Serial section autoradiograms were prepared of different planes of the hypothalamus and diencephalon of immature female, immature male, and ovariectomized mature rats injected with 6,7-
3
H-estradiol-17 β. Known causes of diffusion and redistribution of the label, such as fixation, embedding, and thawing, were eliminated by the use of an autoradiographic technique based on the dry-mounting of freeze-dried sections. Neurons that concentrate estradiol exist in distinct and definable anatomical areas that are independent of the sex and hormonal state of the animals. Distribution of these neurons follows known terminations of the stria terminalis, which supports the concept of an endocrine amygdaloid-hypothalamic-hypophysial axis.
Human-Mouse Somatic Cell Hybrids with Single Human Chromosome (Group E): Link with Thymidine Kinase Activity
Authors: Migeon Barbara Ruben , Miller Carol S.
Published: October 2006

Mouse somatic cells lacking thymidine kinase were mixed in culture with human diploid cells lacking hypoxanthine guanine phosphoribosyl transferase, and hybrid cells were isolated and maintained in a selective medium containing hypoxanthine, aminopterin, and thymidine. The hybrid cells at the time of isolation had karyotypes consisting predominantly of mouse chromosomes but with one human chromosome, a submetacentric member of group E, apparently giving thymidine kinase to the hybrid cell. However, after long-term propagation in the selective medium this chromosome has been lost, although cells continue to show thymidine kinase activity as demonstrated by the incorporation of
3
H-thymidine into DNA in the hybrid cell. The hybrid cells have only mouse electrophoretic variants for glucose-6-phosphate dehydrogenase, lactate dehydrogenase, and malate dehydrogenase, suggesting that the human genetic loci for these enzymes are not represented in the hybrid genome and may be unlinked to that for thymidine kinase.
Anaerobic Brain Function: Effects of Stagnant and Anoxic Anoxia on Persistence of Breathing in Reptiles
Authors: Belkin Daniel A.
Published: October 2006

Turtles tolerate anoxic anoxia about 14 times longer than stagnant anoxia. In snakes and crocodiles this difference is much less marked. Apparently, the remarkable anaerobic viability of turtles is dependent on blood circulation. Analyses of plasma indicate that loss of brain function in anoxic crocodiles is not caused by systemic acidosis or hypoglycemia. It is suggested that the ability of the central nervous system of the turtle to function without oxygen is due to a comparatively high rate of anaerobic uptake or metabolism of glucose.
Oxidation of Ferrous Iron in Vermiculite and Biotite Alters Fixation and Replaceability of Potassium
Authors: Barshad Isaac , Kishk Fawzy M.
Published: October 2006

Oxidation of octahedral ferrous to ferric iron in soil vermiculite clays and biotites increases the potassium-fixation capacity of vermiculites and increases the difficulty of replacing interlayer potassium in biotites. This unexpected effect is believed to be related to an increase in the attractive forces between potassium ions and oxygen ions of the surface layers which is brought about by a tilting of the dipole of the octahedral hydroxyl ions from a perpendicular position to an inclined position with respect to the cleavage plane.
Malignant Argyrophilic Gastric Carcinoids of
Praomys (Mastomys) natalensis
Authors: Snell Katharine C. , Stewart Harold L.
Published: October 2006

Cells of carcinoid tumors which arise in the glandular stomach of old male and female
Praomys
(
Mastomys
) natalensis contain argyrophil granules when tissues fixed in formalin are colored with solutions of silver salts. The carcinoids metastasize in about 25 percent of cases, and are transplantable to other
Mastomys
. Tumor-bearing animals may show gastric and duodenal ulcers and multiple endocrine adenomas.
Direct Resorption of Bone by Human Monocytes
Authors: Mundy Gregory R. , Altman Arnold J. , Gondek Monica D. , Bandelin Janet G.
Published: October 2006

Cultured human peripheral blood monocytes stimulate the release of bone mineral and matrix from killed long bones of fetal rats. These effects were inhibited by cortisol but were not altered by hormones that normally stimulate osteoclastic bone resorption. There was no evidence of morphologic differentiation of the monocytes into osteoclasts during bone resorption.
L-Ascorbic Acid Synthesis in Birds: Phylogenetic Trend
Authors: Chaudhuri C. Ray , Chatterjee I. B.
Published: October 2006

The ability of several species of birds to synthesize L-ascorbic acid is correlated with their phylogeny. In the more primitive species, synthesis of L-ascorbic acid occurs in the kidney. Among the highly evolved passeriform species, kidney and liver can synthesize L-ascorbic acid in some, whereas in others synthesis occurs in the liver. In still others, the capacity for the synthesis of L-ascorbic acid is apparently lost. The pattern of evolution of the ascorbic acid pathway among birds is thus similar to that among mammals.
Simultaneously Recorded Trains of Action Potentials: Analysis and Functional Interpretation
Authors: Gerstein George L. , Perkel Donald H.
Published: October 2006

A new kind of statistical display, the joint peri-stimulus-time scatter diagram, facilitates the analysis and interpretation of two or more simultaneously recorded trains of action potentials. The display is a generalization of the cross correlation and the peri-stimulus-time histogram, and it reflects specific underlying neuronal interactions. The technique yields quantitative measures of interaction in terms of effectiveness of synaptic connections.
Noncovalent Binding of a Spin-Labeled Inhibitor to Ribonuclease
Authors: Roberts Gordon C. K. , Hannah John , Jardetzky Oleg
Published: October 2006

The stable free radical 2,2,6, 6-tetramethyl-4-hydroxypiperidin-1-oxyl monophosphate has been synthesized; it binds to ribonuclease. The selective changes in the nuclear magnetic resonance spectrum of the enzyme produced by the free radical make it possible to define qualitatively the region of the enzyme to which it binds. The radical appears to occupy a site similar to that to which inorganic phosphate binds which is close to or within the active site of the enzyme.
Carcinoma of the Cervix: Deficiency of Nexus Intercellular Junctions
Authors: McNutt N. Scott , Weinstein Ronald S.
Published: October 2006

Intercellar junctions where cell membranes are in intimate contact (nexuses) are very abundant in the epithelium of normal human cervix. Squamous carcinoma cells are deficient in nexuses although a rare nexus is seen. Nexuses may be involved in normal growth regulation, while a deficiency of nexuses may be related to the invasive property of malignant growth.
Carbonado: Natural Polycrystalline Diamond
Authors: Trueb Lucien F. , de Wys E. Christiaan
Published: October 2006

Carbonados are porous aggregates of mostly xenomorphic diamond crystallites ranging in diameter from a fraction of a micron to over 20 microns. Crystalline inclusions (up to 3 percent) occur in the pores of the crystallites and consist mainly of orthoclase and small amounts of other igneous, metamorphic, and secondary minerals.
Particle Track Enhancement in Cellulose Nitrate by Application of an Electric Field
Authors: Crannell Hall , Crannell Carol Jo , Kline F. J. , Battist Lewis
Published: October 2006

The number and length of etchable tracks, created by alpha particles in a cellulose nitrate sheet, are significantly enhanced by the application of an electric field across the cellulose nitrate.
Topological Inconsistency of Continental Drift on the Present-Sized Earth
Authors: Meservey R.
Published: October 2006

Certain continents have in the past moved with respect to each other in a manner clearly implied by sea-floor spreading and other data. However, the resulting collective motion of all the continents was apparently not topologically possible on the present-sized earth. An expanding earth might resolve this difficulty.
Herpes Simplex Virus: Dry Mass
Authors: Lampert Fritz , Bahr Gunter F. , Rabson Alan S.
Published: October 2006

Dry mass of herpes simplex virus particles was measured by quantitative electron microscopy after isolation by surface spreading and critical-point drying of infected cells. The core weighed about 2 × 10
-16
gram, the empty naked capsid 5 × 10
-16
gram, the full naked capsid 7 × 10
-16
gram, and the enveloped nucleocapsid 13 × 10
-16
gram.
Avian Thyroid: Effect of
p
,
p
′-DDT on Size and Activity
Authors: Jefferies D. J. , French M. C.
Published: October 2006

Feeding sublethal amounts of
p
,
p
′-DDT to pigeons caused an increase in thyroid weight and a reduction in colloid content of the follicles. This may reflect a hyper- or hypo-functioning gland and may be connected with recent reductions in egg shell weights in wild birds. The effect was accompanied by increased liver weight.
Simian Virus 40 in Polio Vaccine: Follow-Up of Newborn Recipients
Authors: Fraumeni Joseph F. , Stark Charles R. , Gold Eli , Lepow Martha L.
Published: October 2006

Soon after birth, when susceptibility to carcinogens should be enhanced, a group of children received oral polio vaccine which was later found to contain significant amounts of simian virus 40. Eight years after the incident, no cancer deaths have been observed among the vaccinated children, but continued surveillance is needed before concluding that simian virus 40 is innocuous to man.
Polyploidy in the Common Tree Toad
Hyla versicolor
Le Conte
Authors: Wasserman Aaron O.
Published: October 2006

A karyotype of the first known naturally occurring anuran polyploid in North America is described.
Hyla versicolor
, the common tree toad, is tetraploid (2
n
→4
n
=48). Individual chromosomes representing each set of four of the
Hyla versicolor
karyotype correspond closely with those of the diploid (2
n
= 24)
Hyla andersonii
karyotype.
Thermal Diffusivity and Conductivity of Lunar Material
Authors: Horai Ki-iti , Simmons Gene , Kanamori Hiroo , Wones David
Published: October 2006

The thermal diffusivity and conductivity of type C lunar samples returned by Apollo 11 are lower and less dependent on temperature than those of type A samples. The thermal properties of both types are lower than the corresponding properties of normal terrestrial rocks.
Lateral Hypothalamic Control of Killing: Evidence for a Cholinoceptive Mechanism
Authors: Smith Douglas E. , King Melvyn B. , Hoebel Bartley G.
Published: October 2006

In rats that would not ordinarily kill mice, lateral hypothalamic injection of crystalline carbachol, a cholinomimetic, elicited killing. Norepinephrine, amphetamine, serotonin, and sodium salts were ineffective at the same site. Carbachol was ineffective when injected into the medial, dorsal, or ventral hypothalamus. As additional evidence for a cholinoceptive mechanism, neostigmine elicited killing, and, in spontaneous killers, methyl atropine blocked it. The results indicate that the lateral hypothalamus contains a cholinoceptive component of an innate system that activates killing, and anticholinergic treatment can be used as a means of suppressing killing.
Hormonal Effects on Ontogeny of Swimming Ability in the Rat: Assessment of Central Nervous System Development
Authors: Schapiro Shawn , Salas Manuel , Vukovich Katherine
Published: October 2006

The maturation of swimming behavior and the evoked cortical response to sciatic stimulation were studied in newborn rats receiving thyroxine or cortisol. Compared to that of controls the maturation of swimming is accelerated or delayed 2 to 3 days by thyroxine or cortisol treatment, respectively, and this corresponds to ontogenetic shifts in the characteristics of the evoked potential. Front leg movement during swimming normally diminishes at about 16 days of age and is inhibited by day 22. Thyroxine also advances and cortisol delays the age at which this inhibitory mechanism becomes evident, and compresses (thyroxine) or expands (cortisol) the time interval over which it becomes functional. During early postnatal life certain circulating hormones can affect the rate and chronology of central nervous system maturation. Swimming behavior may be a simple model to use in studies concerned with factors affecting the functional and behavioral development of the central nervous system.
Antagonism by DDT of the Effect of Valinomycin on a Synthetic Membrane
Authors: Hilton B. D. , O'Brien R. D.
Published: October 2006

The potassium conductance which is induced by 10
-6
molar valinomycin in a lecithin-decane membrane is reversed by 3 × 10
-6
molar DDT. Membranes not treated with valinomycin are not affected by DDT. This blockade of potassium conductance parallels the effect of DDT on axonic conduction. Dieldrin and lindane, whose physiological actions are in some ways like those of DDT, do not affect valinomycin-induced conductance of lecithin-decane membranes.
Physiological Responses of Infant Rats to Separation from Their Mothers
Authors: Hofer Myron A.
Published: October 2006

Decreases of 40 percent in cardiac and respiratory rates occur during the first 12 to 16 hours after 2-week-old rat pups are separated from their mothers. These rates decrease without significant alteration in activity level and despite maintenance of body temperature, of nutrition by intubation, of an intact litter, and of the home cage nest.
Thermoresponsiveness of the Preoptic Region of the Brain in House Sparrows
Authors: Mills Steven H. , Heath James Edward
Published: October 2006

Heating the preoptic region of the house sparrow caused the bird to decrease its metabolism and to decrease its body temperature, whereas cooling that region caused an increase in metabolism and an increase in body temperature. These responses indicate that the preoptic region of birds, like that of other vertebrates, is an important center for thermoregulation.
Feline Leukemia and Sarcoma Viruses: Susceptibility of Human Cells to Infection
Authors: Sarma Padman S. , Huebner Robert J. , Basker John F. , Vernon Lee , Gilden Raymond V.
Published: October 2006

Human embryonic cells are highly susceptible to infection with feline leukemia and sarcoma viruses. These viruses were propagated in human cultures without antigenic modification or loss of infectivity for cat or human cells. Virus stocks contained at least 10
6
infectious units of virus per milliliter for human cells. Virus present in 10
-6
dilution of virus stock replicated to detectable amounts as early as 7 days after virus infection. The feline sarcoma virus induced morphological transformation of human cells.
Inhibition of Cytotoxicity of Lymphocytes by Concanavalin A in vitro
Authors: Perlmann Peter , Nilsson Helena , Leon Myron A.
Published: October 2006

Human lymphocytes treated with the plant protein concanavalin A are stimulated to transform into blasts, without developing cytotoxicity for chicken erythrocytes. Prior treatment of lymphocytes with concanavalin A potentiated phytohemagglutinin-induced blast transformation and DNA synthesis but completely inhibited phytohemagglutinin-induced cytotoxicity. Inhibition was not due to suppression of the mixed lymphocyte-erythrocyte aggregation normally caused by phytohemagglutinin. Inhibition of cytotoxicity was reversible when concanavalin A was removed from the lymphocytes by treatment with methyl-α-D-mannopyranoside after 1 hour but not after 20 hours. The results indicate that blast transformation and cytotoxicity are separate expressions of lymphocyte stimulation.
Chromosomal Localization of Mouse Satellite DNA
Authors: Pardue Mary Lou , Gall Joseph G.
Published: October 2006

Hybridization of radioactive nucleic acids with the DNA of cytological preparations shows that the sequences of mouse satellite DNA are located in the centromeric heterochromatin of the mouse chromosomes. Other types of heterochromatin in the cytological preparations do not contain satellite DNA.
Suppression and Elimination of an Island Population of
Culex pipiens quinquefasciatus
with Sterile Males
Authors: Patterson R. S. , Weidhaas D. E. , Ford H. R. , Lofgren C. S.
Published: October 2006

The release of 8,400 to 18,000 males per day of
Culex pipiens quinquefasciatus
Say which had been exposed to a sterilizing agent (thiotepa), suppressed and eliminated an indigenous population of this mosquito on an island off the coast of Florida in a 10-week period. Sterile males were effective in seeking out and mating with females on the island.
Chemical Defense of Brood by a Social Wasp
Authors: Jeanne Robert L.
Published: October 2006

Ants are a constant threat to the nests of tropical social wasps. Adults of the neotropical social wasp
Mischocyttarus drewseni
apply a secretion to the nest stem which is repellent to ants foraging for food by scouting and recruiting, and effectively keeps them from gaining access to the nest and discovering the brood.
Bulk Isolation in Nonaqueous Media of Nuclei from Lyophilized Cells
Authors: Kirsch Wolff M. , Leitner John W. , Gainey Michael , Schulz Demoy , Lasher Robert , Nakane Paul
Published: October 2006

Intact lyophilized nuclei are obtainable from a variety of tissues, either in situ or in culture, by freezing at -156°C, drying at -25°C, and mechanical disassociation in glycerol at 2°C. Centrifugal separation of nuclei is accomplished in an 85 : 15 by volume mixture of glycerol and 3-chloro-1,2 propanediol at 2°C. The method gives homogeneous nuclear preparations in high yield with preservation of labile and water-soluble constituents.
Habituation: Occurrence at a Neuromuscular Junction
Authors: Bruner Jan , Kennedy Donald
Published: October 2006

At the neuromuscular junctions between the motor giant axon and fast flexor muscle fibers in crayfish, stimulation at frequencies of one per minute produces a large decline in the amplitude of excitatory junctional potentials. Recovery (dishabituation) can be brought about by increases in stimulus frequency, which trigger a potentiation process; at still higher frequencies, a second form of depression intervenes. The last process appears to be due to depletion of transmitter; the first probably depends instead upon electrical changes in presynaptic terminals. Because of the interactions between the three processes, the junctions display the properties of habituation and dishabituation usually associated with complex central nervous networks.
Differential Reactivity of Human Serums with Early Antigens Induced by Epstein-Barr Virus
Authors: Henle Werner , Henle Gertrude , Zajac Barbara A. , Pearson Gary , Waubke Rainer , Scriba Marianne
Published: October 2006

Inoculation of 64-10 or Raji cultures with Epstein-Barr virus derived from the HRI-K clone of the P3J Burkitt's lymphoma line caused abortive infections in most of the lymphoblastoid cells with synthesis of "early antigens" but few, if any, capsids. Antibodies to early antigens were detected by indirect immunofluorescence in serums of many patients with infectious mononucleosis, Burkitt's lymphoma, or nasopharyngeal carcinoma. These antibodies were rarely present in other serums even though some of them showed high titers of antibodies to Epstein-Barr virus when assayed on EB3 Burkitt tumor cells; they also prevented synthesis of early antigens, provided the serums were mixed with the virus prior to inoculation. Antibodies to early antigens possibly reflect current or recent disease processes that are associated with the virus.
Hydrogen Bonding in Hydrochloric Acid Solutions
Authors: Lee Sang C. , Kaplow Roy
Published: October 2006

The radial distributions of atom pairs in water and in solutions of hydrochloric acid have been measured by x-ray diffraction. The near-neighbor water correlations are strongly affected by the ions. Part of the experimental distributions is attributed to new oxygen-to-oxygen distances, associated with the presence of excess protons, and these distances become shorter as the concentration of the acid increases.
Cystinosis: Selective Induction of Vacuolation in Fibroblasts by L-Cysteine-D-Penicillamine Disulfide
Authors: Schulman Joseph D. , Bradley Kathryn H.
Published: October 2006

In cultured fibroblasts from individuals with cystinosis vacuolation is induced by exposure to
L-
cysteine
-D-
penicillamine disulfide. Normal fibroblasts do not show vacuolation on such exposure. These observations provide direct evidence that cystinotic cells have deficient activity of a lysosomal system for disulfide metabolism or transport. Induction of vacuolation by the mixed disulfide in cystinotic but not in normal cells furnishes a histological marker for cystinotic fibroblasts.
Aldrin: Removal from Lake Water by Flocculent Bacteria
Authors: Leshniowsky Walter O. , Dugan Patrick R. , Pfister Robert M. , Frea James I. , Randles Chester I.
Published: October 2006

Floc-forming bacteria isolated from Lake Erie adsorb and concentrate aldrin from colloidal dispersion so that the settling of the bacterial flocs removes aldrin from the water phase. Contemporary sediments forming in Lake Erie contain aldrin and could adsorb more. The sediments consist of a conglomerate floc of bacteria, diatoms, and inorganic and detrital particles. Flocculent bacteria also adsorb microparticulates, and this adsorption capacity represents a mechanism for sediment formation and for the removal of suspended particles including aldrin from the water column.
Attention and Psychological Change in the Young Child
Authors: Kagan Jerome
Published: October 2006

This article began by suggesting that different processes are likely to mediate alterations in behavior and cognitive structure and that conditioning principles do not seem sufficient to explain all the classes of change. Although the acquisition of conditioned responses, the potentiation of inborn capacities, and the establishment of schemata probably implicate different processes, all three involve selective attention to sensory events, whether these events function as conditioned stimuli, releasers of innate response dispositions, or the bases for mental representations. Hence, better understanding of the forces that control selectivity and duration of attention should provide insights into the nature of psychological growth, especially the lawful alterations in cognitive structure that seem to occur continually as a function of the child's encounter with discrepant events. The heart of this article was devoted to this theme. It was argued that events that possessed a high rate of change in their physical characteristics, that were moderately discrepant from established schemata, and that activated hypotheses in the service of assimilation had the greatest power to recruit and maintain attention in the young child.
Recognition by Elam-1 of the Sialyl-Le
x
Determinant on Myeloid and Tumor Cells
Authors: Walz Gerd , Aruffo Alejandro , Kolanus Waldemar , Bevilacqua Michael , Seed Brian
Published: October 2006

Endothelial leukocyte adhesion molecule-1 (ELAM-1) is an endothelial cell adhesion molecule that allows myeloid cells to attach to the walls of blood vessels adjacent to sites of inflammation. ELAM-1 recognizes the sialyl-Lewis X (sialyl-Le
x
) determinant, NeuAcα2-3Galβ1-4(Fucα1-3)GlcNAc-, a granulocyte carbohydrate also found on the surface of some tumor cell lines. Binding of myeloid cells to soluble ELAM-1 is inhibited by a monoclonal antibody recognizing sialyl-Le
x
or by proteins bearing sialyl-Le
x
, some of which may participate in humoral regulation of myeloid cell adhesion. Stimulated granulocytes also release an inhibitor of ELAM-1 binding that can be selectively adsorbed by monoclonal antibody to sialyl-Le
x
.
Activity and Distribution of Binding Sites in Brain of a Nonpeptide Substance P (NK
1
) Receptor Antagonist
Authors: McLean Stafford , Ganong Alan H. , Seeger Thomas F. , Bryce Dianne K. , Pratt Kara G. , Reynolds Linda S. , Siok Chester J. , Lowe John A. , Heym James
Published: October 2006

CP-96,345, a nonpeptide substance P antagonist, is selective for the tachykinin NK1 receptor. The compound binds to a single population of sites in guinea pig brain and potently inhibits substance P-induced excitation of locus ceruleus neurons. CP-96,345 should be a useful tool for studying the action of substance P in the central nervous system.
Permeation of Dry Seeds with Chemicals: Use of Dichloromethane
Authors: Meyer Hanna , Mayer A. M.
Published: October 2006

Dichloromethane can be used to introduce chemicals into dry seeds in the absence of water. The solvent has no effect on germination or respiration. The chemicals become effective when the seeds are placed in water under normal conditions for germination. The potential of the new method is discussed.
Detection of Air Pollutants with Tunable Diode Lasers
Authors: Hinkley E. D. , Kelley P. L.
Published: October 2006

Preliminary experiments indicate that tunable Pb

1-
x

Sn

x

Te diode lasers will be useful in the identification and sensitive detection of most of the atmospheric pollutant gases. For point-sampling applications, concentrations in the parts-per-billion range should be measurable with very high specificity. For long-range atmospheric transmission techniques, the improved resolution capability and tunability of these diode lasers make them attractive replacements for spectrometers and fixed-frequency laser sources where operation at cryogenic temperatures is not a serious impediment. By using these lasers as tunable local oscillators in the infrared heterodyne configuration, remote passive detection of gases present in smokestack effluent appears possible. Finally, pulsed operation at temperatures available with simple cryogenic coolers permits immediate application to the fast detection of gases present in automobile exhaust and in chemical processing plants.
Fossil Penguin from the Late Cenozoic of South Africa
Authors: Simpson George Gaylord
Published: October 2006

Spheniscus predemersus
, new species, from the late Pliocene of Langebaanweg, Cape Province, is the first fossil penguin to be described from Africa. It is closely related and possibly ancestral to the living species,
Spheniscus demersus
, of southern and southwestern Africa.
Carbon Monoxide: Association of Community Air Pollution with Mortality
Authors: Hexter Alfred C. , Goldsmith John R.
Published: October 2006

Regression analysis of daily mortality in Los Angeles County shows that there is a significant association between community carbon monoxide concentrations and mortality. Cyclic variation and maximum temperature were the main contributors. No association was demonstrated between oxidant and mortality.
Somatosensory System: Organizational Hierarchy from Single Units in Monkey Area 5
Authors: Duffy F. H. , Burchfiel J. L.
Published: October 2006

The receptive fields of single cells in area 5 of monkey parietal cortex were studied by extracellular recording. Cells were driven primarily by gentle manipulation of multiple joints residing on one or more limbs. Both excitatory and inhibitory convergence were demonstrated. It is postulated that the multijoint receptive fields of area 5 are the result of convergence from single-joint cells of the primary receiving area. An analogy is drawn between the modification of information in the visual and somatosensory systems.
Holocene Eruptions of Mauna Kea Volcano, Hawaii
Authors: Porter Stephen C.
Published: October 2006

Postglacial lava flows, interstratified with thick locally derived sheets of tephra, cover some 27.5 square kilometers on the south slope of Mauna Kea. Most of the volcanics were erupted about 4500 years ago and overlie a regionally extensive paleosol which developed largely during the last glaciation.
Developing Neuromuscular Junctions: First Signs of Chemical Transmission during Formation in Tissue Culture
Authors: Robbins Norman , Yonezawa Takeshi
Published: October 2006

Electrophysiological study of rat neuromuscular junctions in the early stage of formation in tissue culture showed that chemical transmission begins with discrete, localized release of transmitter about the time when nerve-muscle contacts are first visible with light microscopy. Noncontractile myotubes with as few as three nuclei showed evidence of junctional transmission.
Palytoxin: A New Marine Toxin from a Coelenterate
Authors: Moore Richard E. , Scheuer Paul J.
Published: October 2006

Palytoxin has been isolated from the zoanthids "
limu-make-o-Hana
" (Tentatively identified as
Palythoa
sp.) as a noncrystalline, chromatographically pure entity. Apart from polypeptide and protein toxins, it is the most highly toxic substance known, with a lethal dose (LD
59
) in mice of 0.15 microgram per kilogram by intravenous injection. Unlike the potent toxins batrachotoxin, saxitoxin, and tetrodotoxin which have molecular weights of 500 or less, palytoxin has an estimated molecular weight of 3300 and contains no repetitive amino acid or sugar units.
Crystal Structure of L-
N
-Acetylhistidine Monohydrate: An Open and Closed Case
Authors: Kistenmacher Thomas J. , Marsh Richard E.
Published: October 2006

L-N-
Acetylhistidine crystallizes from aqueous solution as the monohydrate. The crystals are triclinic, space group
P
1, with two formula units per cell. The structural solution was accomplished by direct methods. The two independent molecules have very different conformations, one open and one closed. These two conformations are compared with those found in other histidine structures.
Identification of a Competitive HGF Antagonist Encoded by an Alternative Transcript
Authors: Chan Andrew M.-L. , Rubin Jeffrey S. , Bottaro Donald P. , Hirschfield David W. , Chedid Marcio , Aaronson Stuart A.
Published: October 2006

We identified a naturally occurring hepatocyte growth factor (HGF) variant, whose predicted sequence extends only through the second kringle domain of this plasminogen-related molecule. This smaller molecule, derived from an alternative HGF transcript, lacked mitogenic activity but specifically inhibited HGF-induced mitogenesis. Cross-linking studies demonstrated that the truncated molecule competes with HGF for binding to the HGF receptor, which has been identified as the c-
met
protooncogene product. Thus, the same gene encodes both a growth factor and its direct antagonist.
Transcription of Nonrepeated DNA in Mouse Brain
Authors: Hahn William E. , Laird Charles D.
Published: October 2006

Under normal conditions of DNA renaturation, about 60 percent of mouse DNA fragments renature at a rate consistent with their being present only once per sperm. These nonrepeated sequences (also called single-copy or unique) may be used in RNA-DNA hybridization experiments to provide quantitative estimates of RNA diversity. About 10 percent of the mouse single-copy sequences are transcribed in mouse brain tissue. Estimates of about 3 percent were obtained for mouse liver and kidney RNA's. If only one of the complementary DNA strands is transcribed, this hybridization value implies that the equivalent of at least 300,000 different sequences of 1000 nucleotides are expressed in mouse brain tissue. It is suggested that the large amount of DNA in mammals is functionally important, and that a substantial proportion of the genome is expressed in the brain.
Mariner Ultraviolet Spectrometer: Topography and Polar Cap
Authors: Barth Charles A. , Hord Charles W.
Published: October 2006

Mars, the red planet, reflects sunlight in the ultraviolet, but it is the atmosphere, not the surface, that is responsible for the reflected light. Even though there are atmospheric scatterers in addition to the molecular scatterers, it is possible to relate the intensity of the scattered radiation with the atmospheric pressure. The variation of pressure over the planet reveals the topography to vary over 7 kilometers in height and to be correlated with visible features. The carbon dioxide polar cap, in addition to being a cold trap for volatile gases in the atmosphere, may also be a very efficient adsorption trap for nonvolatiles. This last property may make the cap a repository for gases produced by geological or biological activity.
Human Auditory Attention: A Central or Peripheral Process?
Authors: Picton Terence W. , Hillyard Steven A. , Galambos Robert , Schiff Maurice
Published: October 2006

The click-evoked electrical responses of the human cochlear nerve were recorded from the external ear canal concurrently with the cortical evoked potentials from the scalp. Paying attention to the clicks during a discrimination task resulted in a highly significant enhancement of the cortical response but no change in the cochlear nerve response. Hence no evidence was obtained for the operation of a peripheral gating mechanism during attention in man.
Death as an Event: A Commentary on Robert Morison
Authors: Kass Leon R.
Published: October 2006

1) We have no need to abandon either the concept of death as an event or the efforts to set forth reasonable criteria for determining that a man has indeed died.

2) We need to recover both an attitude that is more accepting of death and a greater concern for the human needs of the dying patient. But we should not contaminate these concerns with the interests of relatives, potential transplant recipients, or "society." To do so would be both wrong and dangerous.

3) We should pause to note some of the heavy costs of technological progress in medicine: the dehumanization of the end of life, both for those who die and for those who live on; and the befogging of the minds of intelligent and moral men with respect to the most important human matters.
Light to Hide by: Ventral Luminescence to Camouflage the Silhouette
Authors: Hastings J. Woodland
Published: October 2006

The so-called pony fish of the tropical and subtropical Indo-Pacific region can emit light from a broad area of its ventral surface. An experimental analysis of this luminescent system supports the hypothesis that it functions by emitting light during the daytime, which matches the background light and thereby obscures the silhouette of the animal.
The Scientific Advisory System: Some Observations
Authors: Perl Martin L.
Published: October 2006

The scientific advisory system is effective on limited technical questions, and such questions provide much of its work. On broad technical questions, however, the scientific advisory system is not effective. Unfortunately this category includes most of the crucial environmental questions. Finally, the advisory system, as presently constituted, combined with the multiple functions of the scientific establishment, is detrimental in important ways to the process of technical decision-making in this country. This is because the combined effect of the advisory system and the establishment is to impede the development of a more effective and comprehensive role for the scientific community in the technical decision-making process.
Color- and Edge-Sensitive Channels in the Human Visual System: Tuning for Orientation
Authors: Held Richard , Shattuck Stefanie R.
Published: October 2006

After subjects scanned red stripes tilted clockwise off vertical and green stripes tilted equally but counterclockwise, vertical test stripes appeared tilted counterclockwise when red but clockwise when green. As the angle between scanned and test stripes was increased from 0° to 75°, the magnitude of the tilt aftereffect rapidly increased to a peak between 10° and 15° and then dropped close to zero at about 40°, a result consistent with narrowly tuned edge-sensitive channels.
Ascorbic Acid: A Culture Requirement for Colony Formation by Mouse Plasmacytoma Cells
Authors: Park C. H. , Bergsagel D. E. , McCulloch E. A.
Published: October 2006

Plasmacytoma stem cells explanted from mice formed colonies in culture only in the presence of L-ascorbic acid; this vitamin was not needed for the formation of granulocytic colonies. Isomers of L-ascorbic acid with less antiscorbutic activity also promoted plasmacytoma colony formation, but less effectively. Other redox compounds without antiscorbutic activity and an antioxidant were ineffective.
Neuronal GM
1
Gangliosidosis in a Siamese Cat with β-Galactosidase Deficiency
Authors: Baker Henry J. , Lindsey J. Russell , McKhann Guy M. , Farrell Donald F.
Published: October 2006

A juvenile Siamese cat with severe, progressive motor disability was shown to have extensive neuronal degeneration caused by accumulation of GM
1
ganglioside. Tissues from brain and kidney were markedly deficient in β -galactosidase activity. The disease in this cat is thought to be inherited as an autosomal recessive trait, and is strikingly similar to juvenile GM
1
gangliosidosis of children.
Ice Nucleation by Coprecipitated Silver Iodide and Silver Bromide
Authors: Vonnegut B. , Chessin Henry
Published: October 2006

The ability of silver iodide to cause freezing of supercooled water is improved if up to 30 percent of the iodine atoms in the crystal are replaced with bromine atoms.
Suppression of Urethan-Induced Lung Adenomas in Mice Treated with Trehalose-6,6-Dimycolate (Cord Factor) and Living Bacillus Calmette Guérin
Authors: Bekierkunst A. , Levij I. S. , Yarkoni E. , Vilkas E. , Lederer E.
Published: October 2006

Trehalose-6,6-dimycolate (cord factor), a glycolipid from mycobacteria, suppressed the development of urethan-induced tumors in the lungs of mice to a similar degree as living
Mycobacterium bovis
(strain BCG) bacilli. The inhibition was apparently due to the host cellular reaction caused locally by cord factor.
Mars Radar Observations, a Preliminary Report
Authors: Downs G. S. , Goldstein R. M. , Green R. R. , Morris G. A.
Published: October 2006

Radar observations of a narrow belt of the surface of Mars, centered at 16° south latitude, show a very rugged terrain, with elevation differences greater than 13 kilometers from peak to valley. For nearby points, the relative altitude is measured to 40 meters at best; the precision is worse for points at different latitudes, or widely separated in longitude, because of orbital uncertainties. Some of the larger craters have been resolved, and their depth and, in some cases, the height of the raised rim have been measured. Where high resolution photographs are available, the correlation is excellent.
Cyclic Adenosine Monophosphate Stimulation of Axonal Elongation
Authors: Roisen Fred J. , Murphy Richard A. , Pichichero Michael E. , Braden Wanda G.
Published: October 2006

Elevated concentrations of adenosine 3′,5′-monophosphate induce a variety of cell movements. The role of adenosine 3′,5′-monophosphate in promoting those movements associated with growth prompted our study of in vitro microtubule-dependent axonal elongation. Ganglia treated with adenosine 5′-monophosphate show no enhancement over controls; treatment with adenosine 3′,5′monophosphate or its dibutyryl derivative significantly enhances elongation, as measured by increases in both axonal numbers and length. Our study suggests that adenosine 3′,5′-monophosphate promotes elongation by stimulation of microtubule assembly.
Human Taste Papilla Stimulation: Stability of Quality Judgments over Time
Authors: McCutcheon N. B. , Saunders J.
Published: October 2006

Human taste papillae are sensitive to two or more chemical stimuli. Individual papillae produce stable response patterns (quality and intensity) over a month's time. Hence, the response pattern does not appear to be affected by turnover of receptor cells.
Cytochalasin B: Does It Affect Actin-Like Filaments?
Authors: Forer Arthur , Emmersem J. , Behnke O.
Published: October 2006

An in vitro system was used to test the purported action of cytochalasin B. At concentrations 100 times those used for experiments in vivo, cytochalasin B did not cause the breakdown of F-actin, did not inhibit the transformation of G-actin to F-actin, did not inhibit the binding of heavy meromyosin to F-actin, and did not inhibit the adenosine triphosphate-induced release of heavy meromyosin from F-actin.
Raman Scattering from Flames
Authors: Lapp M. , Goldman L. M. , Penney C. M.
Published: October 2006

Laser Raman scattering data for nitrogen, oxygen, and water vapor have been obtained from hydrogen-air and hydrogen-oxygen flames. The resulting ground-state and upper-state vibrational bands exhibit strong asymmetrical broadening. Experimental spectral profiles have been fitted theoretically to give a new measurement technique for the determination of rotational and vibrational excitation temperatures.
Expression of the Mammalian X Chromosome before and after Fertilization
Authors: Epstein Charles J.
Published: October 2006

The activity of hypoxanthine-guanine phosphoribosyltransferase in unfertilized mouse ova and in mouse embryos at the two-cell stage is proportional to the number of X chromosomes present during oogenesis. This indicates that the enzyme is X-linked in the mouse and that inactivation of the X chromosome does not occur during oogenesis. However, the genetic dosage effect of the X chromosomes is not present after the increase in hypoxanthine-guanine phosphoribosyltransferase activity in the late morula and the blastocyst stages. These results indicate that the X-linked enzyme locus is expressed sometime after fertilization but before the morula stage.
Montmorillonite: Electron Diffraction from Two-Dimensional Single Crystals
Authors: Roberson H. E. , Towe K. M.
Published: October 2006

Some selected area electron diffraction patterns of isolated monocrystalline particles of both Wyoming and Camp Berteaux sodium-monfmorillonites fail to show the mirror plane symmetry required for the accepted structure. A triclinic model deserves consideration.
Hydroxyproline Heterooligosaccharides in
Chlamydomonas
Authors: Miller David H. , Lamport Derek T. A. , Miller Maureen
Published: October 2006

Most of the hydroxyproline in
Chlamydomonas reinhardtii
is glycosidically linked to oligosaccharides and a monosaccharide that are different from the arabinosides found in hydroxyproline-containing plant cell walls previously examined. Of particular interest is the presence of hydroxyproline-
O
-galactose. These differences may be common to the volvocalean green algae and may be related to lower tensile strength of the cell walls of this group of plants.
Crystal Structure of the Solid Electrolyte(C
5
H
5
NH) Ag
5
I
6
at -30°C
Authors: Geller S.
Published: October 2006

The crystal structure of pyridinium hexaiodopentaargentate, (C
5
H
5
NH)Ag
5
i
6
, is unique among those of the halide and chalcogenide solid electrolytes in that face-sharing iodide octahedra as well as face-sharing tetrahedra and face-sharing between octahedra and tetrahedra provide the paths for silver ion transport. There are two formula units in a hexagonal cell, space group
P
6/
mcc
(
D
2

6
h

). At -30°C, the lattice constants are
a
= 11.97 ± 0.02,
c
= 7.41 ± 0.01 Å. The structure has three sets of sites for the silver ions. At -30°C two of these sets are apparently filled with the ten silver ions per unit cell, while the third set of tetrahedrally coordinated general positions is empty. Therefore, the conductivity at this temperature is limited by the thermal excitation of the silver ions into the empty tetrahedra.
Resistance of Wild Norway Rats in North Carolina to Warfarin Rodenticide
Authors: Jackson William B. , Kaukeinen Dale
Published: October 2006

Reports concerning the ineffectiveness of warfarin rodenticide, used at farms and stores in a rural area about 8 kilometers in diameter near Raleigh, North Carolina, prompted subsequent laboratory testing. All of the 25 Norway rats trapped from the area survived 6 days of no-choice feeding of bait containing 0.025 percent (by weight) warfarin.
Potential Energy Surface Including Electron Correlation for F + H
2
→ FH + H: Refined Linear Surface
Authors: Bender Charles F. , O'Neil Stephen V. , Pearson Peter K. , Schaefer Henry F.
Published: October 2006

A priori quantum mechanical calculations have been carried out at about 150 linear geometries for the fluorine plus hydrogen molecule system. An extended basis set of Gaussian functions was used, and electron correlation was treated explicitly by configuration interaction. Comparison with the experimental activation energy and exothermicity suggests that the theoretical potential surface is quite realistic.
Theiler's Virus-Induced Demyelination: Prevention by Immunosuppression
Authors: Lipton Howard L. , Dal Canto Mauro C.
Published: October 2006

The effect of immunosuppression with cyclophosphamide and rabbit antiserum to mouse thymocytes on demyelination induced by Theiler's virus in SJL/J mice was ascertained from Epon-embedded sections (1 micrometer) of the central nervous system. Immunosuppression not only eliminated mononuclear cell infiltrates in the spinal cord white matter, but it also prevented the occurrence of demyelination. These results suggest that demyelination in this infection is immune-mediated.
Inhibition of Chemical Carcinogenesis by Viral Vaccines
Authors: Whitmire Carrie E. , Huebner Robert J.
Published: October 2006

The incidence of 3-methylcholanthrene-induced subcutaneous tumors was significantly reduced by a single injection of inactivated type C RNA viral vaccine. Rauscher leukemia virus vaccine reduced the incidence of sarcomas from 78 to 50 percent in the BALB/cCr mouse. Radiation leukemia virus vaccine and a vaccine from a wild murine leukemia virus derived from a 3-methylcholanthrene tumor reduced the incidence of sarcoma from 86 percent to 33 and 37 percents, respectively, in the C57BL/6 mouse. These reductions in tumor incidence by virus vaccines help support the concept that type C RNA viruses serve as determinants of chemically induced cancer; additional studies of vaccines made with more purified virus preparations are necessary.