bluuebunny/crossref_metadata_2025 huggingface dataset:
Positive-Ion Chemistry: High Yields of Heavy Hydrocarbons from Solid Methane by Ionizing Radiation
Authors: Davis Donald R. , Libby W. F.
Published: October 2006

At 77°K solid methane is polymerized rapidly and efficiently to heavy hydrocarbons by cobalt-60 gamma rays. The product is a viscous oil consisting mainly of saturated and highly branched hydrocarbons containing an average of about 20 carbon atoms per molecule. This would seem to be evidence for positive-ion chemical reactions in the solid state analogous to those previously reported to occur in the gaseous state at pressures above 0.01 mm-Hg. It would thus appear that the solar ionizing ultraviolet radiation (about 1 erg cm
-2
sec
-1
at the earth) must polymerize methane at an appreciable rate under many likely conditions.
Homocitrulline and Homoarginine Synthesis from Lysine
Authors: Ryan Wayne L. , Wells Ibert C.
Published: October 2006

After the injection of L-lysine and uniformly labeled L-lysine-carbon-14 into the rat, labeled homocitrulline and homoarginine are found in the liver and kidney. The ingestion of lysine by seven normal adults results in an increased urinary excretion of homocitrulline and homoarginine. These data suggest the occurrence of an unreported metabolic pathway for lysine in the rat and man.
Complement-Fixing Antigens in Tissue Cultures of Avian Leucosis Viruses
Authors: Armstrong Donald , Okuyan Melahat , Huebner Robert J.
Published: October 2006

Avian sarcoma and leucosis virus preparations grown in chick embryo tissue cultures contained complement-fixing antigens, which were demonstrated with the use of antiserums from hamsters carrying sarcomas induced by the Schmidt-Ruppin strain of avian sarcoma virus. The complement-fixing antigens shared by three different strains of avian leucosis and one strain of avian sarcoma viruses were largely "soluble" (having failed to sediment when centrifuged at 59,364
g
for 70 minutes). Sedimented particles, presumably virus particles, contained the common sarcoma-leucosis antigen as well.
Aortico-Pulmonary Glomus Tissue Distribution and Blood Supply in the Adult Cat
Authors: Verity M. Anthony , Hughes Trevor , Bevan John A.
Published: October 2006

A microscopic, three-dimensional study of the aortico-pulmonary glomus tissue in the adult cat indicates a random, continuous aggregation of glomus tissue extending from the left coronary artery to the ligamentum arteriosum. It was not possible to demonstrate unequivocally specific glomera. Serial section and the injection of the pulmonary artery with India ink failed to show a vessel of supply to glomeric tissue.
Venezuelan Equine Encephalitis Virus from South Florida
Authors: Chamberlain Roy W. , Sudia W. D. , Coleman Philip H. , Work Telford H.
Published: October 2006

Venezuelan equine encephalitis virus was isolated three times from the
Culex (Melanoconion)
species of mosquitoes collected in south Florida in June, July, and October, 1963. Specific antibody was present in 16 of 28
Peromyscus gossypinus
(cotton mice) and 3 of 16
Sigmodon hispidus
(cotton rats) sampled from one of the infected sites in January 1964.
Mutant Gene That Changes Protein Composition and Increases Lysine Content of Maize Endosperm
Authors: Mertz Edwin T. , Bates Lynn S. , Nelson Oliver E.
Published: October 2006

Preliminary tests have shown that the endosperms of maize seeds homozygous for the
opaque-2
mutant gene have a higher lysine content than normal kernels. As a critical test, a backcross progeny was divided into
opaque-2
and normal kernels, the endosperms separated, and the amino acids determined. The
opaque-2
endosperms had a different amino acid pattern and 69 percent more lysine than the normal seeds. The major reason for these changes is the synthesis of proteins with a greater content of basic amino acids in the acid-soluble fraction of the mutant endosperm. This is accompanied by a reduction in the ratio of zein to glutelin.
Homograft Sensitivity Induction by Group A Streptococci
Authors: Rapaport Felix T. , Chase Randolph M.
Published: October 2006

Streptococcal cells can induce in the guinea pig a state of altered reactivity to skin homografts similar to that resulting from sensitization with homologous tissue.
Polydactylism in the Offspring of Mice Injected with 5-Bromodeoxyuridine
Authors: DiPaolo Joseph A.
Published: October 2006

The intraperitoneal injection of multiple doses of 5-bromodeoxyuridine (BUDR) into pregnant mice produced abnormalities limited to the hind limbs of the offspring. This effect is probably a result of a metabolic lesion. When injected into newborn mice, BUDR did not increase the incidence of tumors.
Extracellular Polysaccharides of Algae: Effects on Life-Support Systems
Authors: Moore B. G. , Tischer R. G.
Published: October 2006

The amount of extracellular polysaccharide produced by eight species of green and blue-green algae ranges from 174 milligrams per liter to 557 milligrams per liter. Most of the polymers are composed of four monosaccharides: a hexose, a pentose, a methyl pentose, and uronic acid. The production of excessive amounts of these photosynthetic end products will undoubtedly influence the effective recycling time of growth media in life-support systems.
Electroencephalographic Correlogram Ratios and Their Stability
Authors: Daniel Robert S.
Published: October 2006

Autocorrelations of electroencephalograms can be reduced to ratios of estimated power among distinguishable parameters of typical tracings: the dominant rhythm, background activity, abundance, and total power. These data reduction methods permit statistical evaluation of differences among experimental conditions, thus extending the usefulness of graphic correlograms in research. Ratios discriminate between two experimental conditions and two subjects, while showing stability over days.
Reversible Cold Block of the Specialized Cardiac Tissues of the Unanesthetized Dog
Authors: Lister John W. , Hoffman Brian F. , Kavaler Frederic
Published: October 2006

The sinoatrial node and the bundle of His in intact, unanesthetized dogs were subjected to local cooling by means of surgically implanted devices. Impulse formation in the sinoatrial node could thus be suppressed at will and the heart rate regulated within a physiological range by an electrode driving the atrium. Reversible blockage of atrioventricular conduction was easily induced on cooling the region of the bundle of His.
Shell Growth and Structure of Planktonic Foraminifera
Authors: Bé Allan W. H. , Lott Leroy
Published: October 2006

Planktonic foraminiferal tests show bilamellar additions to each chamber and develop a "secondary thickening" in the form of a calcite crust in late ontogeny. The evidence presented indicates that additional calcium carbonate is deposited upon the original bilamellar test and that maximum calcite crust thickness is attained at depths greater than 500 meters
Molecular Structure of the Synthetic Molecular Oxygen Carrier O
2
IrCl(CO)(P[C
6
H
5
]
3
)
2
Authors: Ibers James A. , La Placa Sam J.
Published: October 2006

The synthetic molecular oxygen carrier O
2
IrCl(CO)(P[C
6
H
5
]
3
)
2
, discovered by Vaska, has been characterized in a complete molecular structure determination. The structure surmised by Vaska from spectroscopic data has been confirmed and, in addition, definitive details on the attachment of molecular oxygen to iridium in this 1 : 1 reversible oxygen carrier have been obtained. The two oxygen atoms are equidistant from the metal atom, as in Griffith's model of the oxygen atoms in oxyhemoglobin. The O-O bond length of 1.30 ± 0.03 Å is intermediate between those characteristic of O
2
(1.20 Å) and O
2
-2
(1.48 Å), and corresponds closely to O
2
-
(1.28 Å)
"Red" Skeletal Muscle Fibers: Relative Independence of Neural Control
Authors: Bajusz Eörs
Published: October 2006

Studies on skeletal muscle of rats and mice indicate significant differences between the behaviors of the two basic types of muscle fibers during the development of denervation atrophy. While the diameter of fibers possessing sarcoplasmic granularity ("red" fibers) is preserved for a long time after complete severance of motor and sensory nerves, fiber with agranular cytoplasm ("white" fibers) undergo rapid atrophy. It is concluded that, at least in this respect, the "white" fibers are more dependent on neural control than are the "red" fibers.
Method for Discriminative Avoidance Training
Authors: Hurwitz H. M. B.
Published: October 2006

Experiments were performed in which the typical procedure for obtaining discriminated avoidance behavior with rats in a lever-pressing apparatus was compared with a new procedure which allowed only avoidance but not escape from the shock. When either escape or avoidance is possible, the rats make a majority of escape responses, but where escape is impossible avoidance behavior is rapidly established.
Waterfall Sequence for Intrinsic Blood Clotting
Authors: Davie Earl W. , Ratnoff Oscar D.
Published: October 2006

A simple waterfall sequence is proposed to explain the function of the various protein clotting factors during the formation of the fibrin clot. When clotting is initiated, each clotting factor except fibrinogen is converted to a form that has enzymatic activity. This activation occurs in a stepwise sequence with each newly formed enzyme reacting with its specific substrate, converting it to an active enzyme.
Genetic Activity in a Heterochromatic Chromosome Segment of the Tomato
Authors: Khush Gurdev S. , Rick Charles M. , Robinson Richard W.
Published: October 2006

The first example of genetic activity within a heterochromatic region of the tomato is provided by the delimitation of
nv
to the long arm of chromosome 9 by means of the induced deficiency method. A close spatial relationship between
nv
and
ah
was established by deficiencies for
ah
in the same arm and by linkage tests between the two genes.
Compact Bone Deficiency in Protein-Calorie Malnutrition
Authors: Garn Stanley M. , Rohmann Christabel G. , Behar Moises , Viteri Fernando , Guzman Miguel A.
Published: October 2006

Children hospitalized for acute protein-calorie malnutrition in Guatemala City were not delayed in ossification status as compared with Guatemalan Indian children on their customary low-protein diets, but were markedly and often dramatically deficient in cortical bone.
Consequences of Replication Fork Movement Through Transcription Units in Vivo
Authors: French Sarah
Published: October 2006

To examine the basis for the evolutionary selection for codirectionality of replication and transcription in
Escherichia coli
, electron microscopy was used to visualize replication from an inducible ColE1 replication origin inserted into the
Escherichia coli
chromosome upstream (5′) or downstream (3′) of
rrnB
, a ribosomal RNA operon. Active
rrnB
operons were replicated either in the same direction in which they were transcribed or in the opposite direction. In either direction, RNA polymerases were dislodged during replication. When replication and transcription were codirectional, the rate of replication fork movement was similar to that observed in nontranscribed regions. When replication and transcription occurred in opposite directions, replication fork movement was reduced.
A System for Studying Microbial Morphogenesis: Rapid Formation of Microcysts in
Myxococcus xanthus
Authors: Dworkin Martin , Gibson Sally M.
Published: October 2006

A method has been found for inducing the rapid, quantitative, and relatively synchronous conversion of vegetative rods of a fruiting myxobacterium to microcysts. The conversion is induced by the addition of 0.5
M
glycerol to a dispersed, growing, liquid culture of
Myxococcus xanthus
. The vegetative rods are converted to microcysts in about 120 minutes.
Serotonin Rhythm in the Pineal Organ: Control by the Sympathetic Nervous System
Authors: Fiske Virginia M.
Published: October 2006

The serotonin content of the pineal organ of the rat varies diurnally in relation to the photoperiod. When the sympathetic nerves to the pineal are interrupted by the removal of the superior cervical ganglia, no such fluctuation in the serotonin content of the pineal occurs.
Crystal and Molecular Structure of Ferrichrome A
Authors: Zalkin Allan , Forrester J. D. , Templeton David H.
Published: October 2006

The crystal structure of ferrichrome A (C
41
H
58
N
9
O
20
Fe⋅4H
2
O) has been determined by x-ray diffraction. The amino acid sequence in the hexapeptide ring is confirmed to be -Orn-Orn-Orn-Ser-Ser-Gly-, and the conformation of this ring is trans at each peptide linkage. The absolute configuration of the three hydroxamate rings at the iron atom is that of a left-handed propeller. Disorder is found concerning the positions of some of the side chains and one of the four water molecules.
Imprinting in an Altricial Bird: The Blond Ring Dove (
Streptopelia risoria
)
Authors: Klinghammer Erich , Hess Eckhard H.
Published: October 2006

Newborn ring doves were taken away from their parents when they were from 4 to 14 days old. They were then either raised by hand in complete visual isolation from other members of their species or placed in a community cage after weaning. They were tested as adults in a free-choice situation between human beings and ring doves. An optimum period for imprinting was found when they were about 7 to 9 days old. The controls showed that subsequent experiences during the life span of a bird also have an effect on the choice of a mate, and, in this species, imprinting can be said to be reversible.
Sea-to-Air Transport of Surface Active Material
Authors: Blanchard Duncan C.
Published: October 2006

Fine platinum wires were used to collect airborne particulate matter along the shore in Hawaii. This matter was examined for surface active material and for sea salt. Droplets that rise from the sea in the surf zone appear to carry a highly compressed surface active film.
Semipermeable Microcapsules
Authors: Chang Thomas M. S.
Published: October 2006

Simple methods have been developed for encapsulating aqueous solutions of protein within polymer membranes. Stable microcapsules 1 to 100 μ in diameter, with semipermeable membranes, can be made by depositing polymer around emulsified aqueous droplets, either by interfacial coacervation or by interfacial polycondensation. Aqueous suspensions of enzyme-loaded microcapsules act well on small-molecular substrates both in vitro and in vivo.
Heart Action Potential: Dependence on External Calcium and Sodium Ions
Authors: Orkand R. K. , Niedergerke R.
Published: October 2006

The height of the overshoot of the action potential recorded from frog ventricles is markedly less sensitive to lowering the external sodium concentration than predicted by the sodium-hypothesis of excitation, and it is surprisingly sensitive to changes in the external calcium concentration. These observations are explained by a mechanism in which there is competition between sodium and calcium ions, in the excitable membrane, for anionic sites which control the inward current of sodium ions at the crest of the action potential.
Microvibrations in Man and Dolphin
Authors: Haider Manfred , Lindsley Donald B.
Published: October 2006

Microvibrations were recorded from the dorsal body surface of a bottle-nosed dolphin (
Tursiops truncatus
) while it swam in water and while it lay on a foam rubber mattress in an air environment. Unlike poikilothermic water-living animals which do not manifest microvibrations, this homeothermic mammal has 13-cycle per second microvibrations similar to those of man and other homeotherms. For comparative purposes, microvibrations of 11 cycles per second were recorded from the arm of a man while lying on the same mattress. The nature and origin of these microvibrations is discussed in relation to physiological tremors and shivering.
Actinomycin D: An Effect on Rat Liver Homogenates Unrelated to Its Action on RNA Synthesis
Authors: Revel Michel , Hiatt Howard H. , Revel Jean-Paul
Published: October 2006

Liver homogenates prepared from rats injected with high doses of actinomycin D show a decrease in polyribosome content and in amino acid incorporation. These effects are not observed in rat liver not subjected to homogenization and are independent of the inhibition of RNA synthesis caused by the antibiotic.
Accurate Length Measurement of Meter Bar with Helium-Neon Laser
Authors: Mielenz K. D. , Cook H. D. , Gillilland K. E. , Stephens R. B.
Published: October 2006

A helium-neon gas laser has been successfully used in conjunction with an automatic fringe-counting interferometer to measure the length of a meter bar. The agreement obtained was 7 parts in 100 million with respect to the assigned length of the bar.
Interaction of U6 snRNA with a Sequence Required for Function of the Nematode SL RNA in Trans-Splicing
Authors: Hannon Gregory J. , Maroney Patricia A. , Yu Yi-Tao , Hannon Gretchen E. , Nilsen Timothy W.
Published: October 2006

Nematode trans-spliced leader (SL) RNAs are composed of two domains, an exon [the 22-nucleotide spliced leader] and a small nuclear RNA (snRNA)-like sequence. Participation in vitro of the spliced leader RNA in trans-splicing reactions is independent of the exon sequence or size and instead depends on features contained in the snRNA-like domain of the molecule. Chemical modification interference analysis has revealed that two short sequence elements in the snRNA-like domain are necessary for SL RNA activity. These elements are sufficient for such activity because when added to a 72-nucleotide fragment of a nematode U1 snRNA, this hybrid RNA could participate in trans-splicing reactions in vitro. One of the critical sequence elements may function by base-pairing with U6 snRNA, an essential U snRNA for both cis- and trans-splicing.
Probiotics: Growth-Promoting Factors Produced by Microorganisms
Authors: Lilly Daniel M. , Stillwell Rosalie H.
Published: October 2006

Several species of protozoa, during their logarithmic phases of growth, produce substances that prolong the logarithmic phase in other species. The effect is not as striking as the inhibition of growth caused by antibiotics, but a consistent 50-percent increase in growth has been obtained with
Tetrahymena pyriformis
in response to a factor produced by
Colpidium campylum.
Micropuncture Study of Inulin Absorption in the Rat Kidney
Authors: Gutman Yehuda , Gottschalk Carl W. , Lassiter William E.
Published: October 2006

By means of a microinjection technique, inulin-carboxyl-C
14
or inulin-methoxy-H
3
was injected into single proximal tubules of the rat at various urine flow rates. Urine collected separately from the two kidneys showed negligible amounts of inulin activity on the noninjected side, thus demonstrating directly that there is no significant reabsorption of inulin by the renal tubular epithelium under these conditions.
Chemical Background of Silicones
Authors: Hyde J. F.
Published: October 2006

The silicones are in most cases relatively complex mixtures rather than pure molecular species. Their structures and chemical properties can be controlled, however, with sufficient reproducibility to give compositions with unique characteristics. The organic groups serve not only as a device for controlling the siloxane structures, but offer an important means of modifying the physical and chemical properties. Studies of the inductive effects in the organosilicon compounds enhance our understanding of the nature of chemical bonds. In each field of application an extensive technology has developed for the adaptation of silicones to special needs. The possibility of new compositions to serve science and technology seems to be unlimited.
Animal Communication
Authors: Sebeok Thomas A.
Published: October 2006

Semiotics and ethology have converged in a new behavioral science, zoosemiotics. Those who are interested in the theoretical analysis of the complex problems of non-verbal behavior that arise where these two disciplines interact aim to treat comprehensively animal communication systems by the aid of representations that have proved illuminating in the study of sentences of human language. Students of zoosemiotics are concerned with codes and messages much as linguists are concerned with competence, or language, and performance, or speech. They thus face the twin tasks of constructing a model for the addresser to specify how a message is encoded and transformed into a signal carried by a variety of channels to the addressee; and of constructing a model for the addressee to specify the ways in which animals utilize their knowledge of their code to recognize the messages they receive. Finally, they assess the context of the communicative event in the hope of dissecting that which is relevant to the selection process from the rest of the background, a program for which there is as yet neither a procedural eliciting technique nor a satisfactory theoretical solution in sight.
Suspended Matter in Deep Ocean Water
Authors: Ewing Maurice , Thorndike Edward M.
Published: October 2006

A nepheloid layer has been observed by optical means in the lower part of the water column on the continental slope and rise. By sampling it has been found to be a suspension of lutite, apparently in sufficient quantity to induce downslope flow. Sediment transported in the nepheloid layer may be a major component of deep-sea sediment bodies.
Sarcoplasmic Reticulum: Ultrastructure of the Triadic Junction
Authors: Fahrenbach Wolf H.
Published: October 2006

The appositional region between the intermediate element and adjacent cisternae in the triads of the sarcoplasmic reticulum of striated muscle from humans, copepods, ostracods, and barnacles shows a five-layered construction similar to that of a tight junction. Known functions of tight junctions and cisternal elements suggest that a membrane depolarization, conducted by the intermediate element, is transmitted to the cisternae by way of the triadic junction to cause a release of calcium ions from the cisternae.
Sodium Pump: Its Electrical Effects in Skeletal Muscle
Authors: Frumento Antonio S.
Published: October 2006

The variations in the membrane potentials of skeletal muscle fibers which follow high rates of sodium extrusion are not due to changes in the ionic concentrations of the fiber; experiments suggest that sodium is extruded by an electrogenic mechanism.
Relative Radiosensitivities of Woody and Herbaceous Spermatophytes
Authors: Sparrow Rhoda C. , Sparrow Arnold H.
Published: October 2006

The sensitivities of several woody and herbaceous species to single acute exposures to cobalt-60 gamma rays have been determined. Within each group the sensitivity of each species is largely determined by its average interphase chromosome volume (interphase nuclear volume divided by chromosome number) of shoot apical meristem cells. On the basis of the calculated amounts of energy absorbed (in kiloelectron volts) per interphase chromosome at an exposure necessary to produce a given biological effect, woody species were approximately twice as sensitive as herbaceous species.
Growth and Tissue Formation from Single, Isolated Tobacco Cells in Microculture
Authors: Vasil Vimla , Hildebrandt A. C.
Published: October 2006

Single, isolated cells of tobacco divided and grew to form small colonies of over 50 cells in microcultures with a medium containing fresh liquid coconut milk, but in the absence of neighboring cells or nurse tissue. Subsequently, the mass of cells obtained from the single cell, when transferred to agar coconut milk medium, established itself as a clone of callus tissue. Some of these single-cell clones showed differentiation of many tracheid-like cells and shoots with small leaves.
Blue-Green Algae: Fine Structure of the Gas Vacuoles
Authors: Bowen C. C. , Jensen T. E.
Published: October 2006

The gas vacuoles seen in several species of blue-green algae under the light microscope are shown by electron microscopy to correspond to packed arrays of cylindrical, electron-transparent vesicles. Single vesicles average 75 millimicrons in diameter, range from 0.2 micron to 1.0 micron in length, have conical ends, and are bounded by a single membrane 2 millimicrons wide. The reversible disappearance of gas vacuoles induced by sudden application of pressure is accompanied by a reversible collapse of the individual gas vesicles.
Sex Chromatin in Newborns: Presumptive Evidence for External Factors in Human Nondisjunction
Authors: Robinson Arthur , Puck Theodore T.
Published: October 2006

An incidence of 0.6 percent of sex-chromosome aberrations in newborns was found during a 5-month period, while no aberrations occurred in similar populations before and after this period. Down's syndrome also exhibited an elevated frequency during this same critical interval. A severe rubella epidemic may have influenced this pattern.
Biological Formation of Molecular Hydrogen
Authors: Gray Clarke T. , Gest Howard
Published: October 2006

From a general standpoint, the formation of molecular hydrogen can be considered a device for disposal of electrons released in metabolic oxidations. We presume that this means of performing anaerobic oxidations is of ancient origin and that the hydrogen-evolving system of strict anaerobes represents a primitive form of cytochrome oxidase, which in aerobes effects the terminal step of respiration, namely the disposal of electrons by combination with molecular oxygen. We further assume that the original pattern of reactions leading to H
2
production has become modified in various ways (with respect to both mechanisms and functions) during the course of biochemical evolution, and we believe that this point of view suggests profitable approaches for clarifying a number of problems in the intermediary metabolism of microorganisms which produce or utilize H
2
. Of special general importance in this connection is the basic problem of defining more precisely the fundamental elements in the regulatory control of anaerobic energy metabolism. Among the more specific aspects awaiting further elucidation are: the relations between formation of H
2
and use of H
2
as a primary reductant for biosynthetic purposes; the various forms of direct and indirect interactions between hydrogenase and N
2
reduction systems; and the transitional stages between anaerobic and aerobic energy-metabolism patterns of facultative organisms.
Carotid Sinus and Aortic Reflexes in the Regulation of Circulation during Sleep
Authors: Guazzi Maurizio , Zanchetti Alberto
Published: October 2006

In the cat with intact sinoaortic reflexes, episodes of deep sleep are accompanied by marked falls in both systolic and diastolic blood pressure. The falls are much larger after bilateral sino-aortic deafferentation: to such low pressures during deep sleep that episodes of transient cerebral ischemia (electroencephalographic flattening and seizures) sometimes occur.
Ergoline Alkaloids in Tropical Wood Roses
Authors: Hylin John W. , Watson Donald P.
Published: October 2006

Extracts of
Argyreia nervosa
, a tropical wood rose, contain appreciable quantities of ergoline alkaloids tentatively identified as ergine isoergine, and penniclavine together with related substances.
Complexes of F-Pili and RNA Bacteriophage
Authors: Valentine Raymond C. , Strand Mette
Published: October 2006

Cell-free filtrates of F
+
strains of
Escherichia coli
"inactivate" RNA phages. The active agents have been identified in the electron microscope as thin appendages called F-pili. Complexes of F-pili and phage may be easily assayed because of their retention by membrane filter pads. Calcium ion is required for formation of the complex.
Vanillin,
Cis
-Terpin Hydrate, and
Cis
-Terpin as Ice Nucleators
Authors: Power B. A. , Power R. F.
Published: October 2006

Vanillin,
cis
-terpin hydrate, and
cis
-terpin cause ice nucleation at relatively high threshold temperatures. Trace quantities of these substances should exist in the natural atmosphere and may act as ice nuclei.
Functional Studies of Cultured Brain Tissues as Related to "Demyelinative Disorders"
Authors: Bornstein Murray B. , Crain Stanley M.
Published: October 2006

The serums from animals with experimental allergic encephalomyelitis and humans with multiple sclerosis produce, in addition to demyelination, rapid, reversible alterations in complex, evoked bioelectric (synaptic) responses of cultured cerebral cortex and spinal cord tissues of the mouse. The active factors are dependent on complement and are not present in serums from normal animals and humans.
Plant Growth Retardant B-995: A Possible Mode of Action
Authors: Reed Donald J. , Moore Thomas C. , Anderson James D.
Published: October 2006

Inhibition of shoot elongation in dwarf and tall peas by the 1,1-dimethylhydrazide of succinic acid (B-995) was correlated with the inhibition of the oxidation of tryptamine-2-C
14
to indoleacetaldehyde-2-C
14
in homogenates prepared from epicotyls of young plants treated with B-995. The growth-retarding action of B-995 is attributed to the formation of 1,1-dimethylhydrazine in vivo. This hydrazine strongly inhibited tryptamine oxidation by pea epicotyl homogenates.
Hereditary Absence of Sebaceous Glands in the Mouse
Authors: Gates Allen H. , Karasek Marvin
Published: October 2006

An autosomal recessive mutation, characterized by an absence of sebaceous glands, and by hyperkeratosis, alopecia, and single (rather than the usual multiple) hair-follicle units, has occurred spontaneously in the BALB/c strain of mouse. Studies in which reciprocal transplantations of skin were made between normal and mutant mice suggest that some diffusible substance(s) synthesized by normal skin can stimulate hair growth and alleviate the hyperkeratosis characteristic of the skin syndrome.
DNA Synthesis in Aluminum-Treated Roots of Barley
Authors: Sampson M. , Clarkson D. , Davies D. D.
Published: October 2006

When cell division in barley roots is halted by treatment with aluminum, DNA synthesis continues. However, the type of DNA synthesized has an unusual base composition and is metabolically labile. A part of this labile DNA was found in the form of a hybrid composed of genetic DNA and labile DNA.
Chilocorus similis
Rossi: Disinterment and Case History
Authors: Smith Stanley G.
Published: October 2006

Cytological proof is presented that the Asiatic predator
Chilocorus similis
(Coleoptera, Coccinellidae), liberated in California sometime between the years 1923 and 1947, has since been masquerading there under the name
C. orbus
.
Xenon-Photosensitized Formation of Metastable Nitrogen
Authors: Jackson William M. , Scheer Milton D.
Published: October 2006

Metastable nitrogen molecules are produced by collision with xenon atoms excited with 1470-Å radiation. The photolytically excited species were detected by measuring the rate at which electrons were ejected from a gold surface. Hydrogen was shown to be more efficient than helium in quenching the photo-excited xenon atoms.
Hexamethylenetetramine Hexahydrate: A New Type of Clathrate Hydrate
Authors: Jeffrey G. A. , Mak T. C. W.
Published: October 2006

Hexamethylenetetramine hexahydrate has a three-dimensional framework structure of hydrogen-bonded water molecules. Each hexamethylenetetramine molecule is located in a cavity within this framework but is linked to the water structure by hydrogen-bonds through three of its four nitrogen atoms.
Suppression in vitro: Identification of a Serine-sRNA as a "Nonsense" Suppressor
Authors: Capecchi Mario R. , Gussin Gary N.
Published: October 2006

In a cell-free system, with RNA from a suppressible mutant of bacteriophage R17 as messenger,. no functional coat protein of the bacteriophage is synthesized unless serine-accepting soluble RNA from the suppressor strain,
Escherichia coli
S26RIE, is present.
Pliocene-Pleistocene Boundary, Northern Gulf of Mexico
Authors: Akers W. H.
Published: October 2006

Changes in planktonic microfossil assemblages in Atlantic and Pacific sediment cores of Late Cenozoic age correspond in a general way with a horizon recognized in neritic sediments of the northern Gulf of Mexico. Geological evidence from the Gulf Coast indicates that the changes occurred near the end of the Aftonian interglaciation of the early Pleistocene rather than at the end of the Pliocene, as proposed by other investigators.
Ureyite, NaCrSi
2
O
6
: A New Meteoritic Pyroxene
Authors: Frondel Clifford , Klein Cornelis
Published: October 2006

The new mineral NaCrSi
2
O
6
(ureyite) has been found as rare emerald-green grains in the iron meteorites Coahuila, Toluca, and Hex River Mountains. X-ray studies of the natural and synthetic material have established that the mineral is isostructural with jadeite, NaAlSi
2
O
6
. Indexed data for powder patterns obtained by x-ray diffraction and precise cell dimensions are given for the Cr, Fe, and Al members of the jadeite group. Unlike jadeite, a high-pressure phase, ureyite can be synthesized from melts at 1-atmosphere pressure.
Productivity of Microalgae in Antarctic Sea Ice
Authors: Burkholder Paul R. , Mandelli Enrique F.
Published: October 2006

Midsummer productivity of Antarctic microalgae, commonly occurring in brown sea ice along the west coast of the Palmer Peninsula, averaged more than 900 milligrams of carbon per cubic meter per hour, with an assimilation number of about 2.6. The rate of photosynthesis increased with light intensity to a maximum of about 18,000 lux, above which some inhibition was observed. The floral composition, genesis, and physiological properties of these ice communities are different from the epontic under-ice diatoms previously studied by other investigators in McMurdo Sound.
Merrihueite, A New Alkali-Ferromagnesian Silicate from the Mezö-Madaras Chondrite
Authors: Dodd Robert T. , Van Schmus W. Randall , Marvin Ursula B.
Published: October 2006

Merrihueite, a new mineral with the approximate chemical composition (K,Na)
2
(Fe,Mg)
5
Si
12
O
30
, occurs with iron-rich olivine, iron-poor pyroxene, and nickel-iron in a few chondrules of the Mezö-Madaras chondrite. The refractive index lies between 1.559 and 1.592; the birefringence for each composition is low to moderate. X-ray powder data for merrihueite are nearly identical to those for osumilite, (K,Na,Ca)(Mg,Fe)
2
(Al,Fe)
3
(Si,Al)
12
O
30
⋅H
2
O, and very similar to those for synthetic K
2
Mg
5
Si
12
O
30
. Merrihueite is interpreted as an alkali-ferromagnesian silicate mineral of the osumilite type. It is named in honor of the late Craig M. Merrihue, meteoriticist, of the Smithsonian Astrophysical Observatory.
Brucite in Carbonate Secreted by the Red Alga
Goniolithon
sp.
Authors: Schmalz R. F.
Published: October 2006

X-ray diffraction studies, chemical analyses, infrared-absorption studies, and nuclear-magnetic-resonance spectrum analysis demonstrate the existence of the mineral brucite, Mg(OH)
2
, in the skeletal carbonate secreted by the red marine alga
Goniolithon
sp. Electron microprobe examination of the carbonate shows that the brucite is concentrated in certain areas of the skeletal structure. These results explain the anomalously high solubility and large cell size of the
Goniolithon
"carbonate" observed by earlier investigators.
Immunoglobulin Structure: Partial Amino Acid Sequence of a Bence Jones Protein
Authors: Titani Koiti , Whitley Edward , Avogardo Laurel , Putnam Frank W.
Published: October 2006

Sequence analysis and ordering of the soluble tryptic peptides of one Bence Jones protein and comparison with partial sequence data for another have revealed many structural differences in the half of the molecule with the terminal amino group, but only one structural difference in the half of the molecule having the terminal carboxyl group. Somatic chromosomal rearrangements may effect such changes and account for variability in antibody structure.
Turnover of Ribosomal RNA in Rat Liver
Authors: Loeb John N. , Howell R. Rodney , Tomkins Gordon M.
Published: October 2006

After a single injection of radioactive orotic acid and a "chase" of nonradioactive precursor, the specific activity of ribosomal RNA in rat liver decreases logarithmically at a rate corresponding to a half-life of about 5 days. The possible significance of this result is discussed with regard to control of protein synthesis.
DNA: Reaction with Chloroquine
Authors: Allison James L. , O'Brien Richard L. , Hahn Fred E.
Published: October 2006

Difference spectrophotometry shows that double-stranded DNA produces marked changes in the absorption spectrum of chloroquine; only minor changes occur with single-stranded DNA. A DNA-chloroquine complex was demonstrated to sediment in the analytical ultracentrifuge. Chloroquine strongly elevated the thermal dissociation temperature, T
m
, of DNA. It is concluded that the drug forms a complex with DNA by ionic interaction and stabilizes the helix.
The Location of Bound Lipid in the Lipovitellin Complex
Authors: Timmins P. A. , Poliks B. , Banaszak L.
Published: October 2006

The location of the bound lipid in the soluble lipoprotein lipovitellin has been determined by neutron crystallographic techniques. With the use of the contrast variation method, whereby the crystals are soaked in different H
2
O-D
2
O mixtures, the lipid has been found to occupy a large cavity in the protein whose structure had previously been determined by x-ray crystallography. The lipid appears to be bound in the form of a bilayer with the major protein-lipid interactions being hydrophobic and with the lipid headgroups projecting into the bulk solvent and into a solvent-filled space in the cavity.
Neuronal Domains in Developing Neocortex
Authors: Yuste Rafael , Peinado Alejandro , Katz Lawrence C.
Published: October 2006

The mammalian neocortex consists of a mosaic of columnar units whose development is poorly understood. Optical recordings of brain slices labeled with the fluorescent calcium indicator fura-2 revealed that the neonatal rat cortex was partitioned into distinct domains of spontaneously coactive neurons. In tangential slices, these domains were 50 to 120 micrometers in diameter; in coronal slices they spanned several cortical layers and resembled columns found in the adult cortex. In developing somatosensory cortex, domains were smaller than, and distinct from, the barrels, which represent sensory input from a single vibrissa. The neurons within each domain were coupled by gap junctions. Thus, nonsynaptic communication during cortical development defines discrete multicellular patterns that could presage adult functional architecture.
Structure of Ice VI
Authors: Kamb Barclay
Published: October 2006

Ice VI, a high-pressure form of density 1.31 g cm-
3
, has a tetragonal cell of dimensions
a
= 6.27 Å,
c
= 5.79 Å, space group
P
4
2
/
nmc
, each cell containing ten water molecules. The structure is built up of hydrogen-bonded chains of water molecules that are analogs of the tectosilicate chains out of which the fibrous zeolites are constructed. The chains in ice VI are linked laterally to one another to form an open, zeolite-like framework. The cavities in this framework are filled with a second framework identical with the first. The two frameworks interpenetrate but do not interconnect, and the complete structure can thus be considered a "self-clathrate." This structural feature is a natural way to achieve high density in tetrahedrally linked framework structures.
Nucleoside Phosphatases of Fetal and Maternal Blood Cells: Electron Microscope Study
Authors: Connell Reid S. , Bacon Robert L.
Published: October 2006

Surface membranes of the blood cells located within the maternal blood sinuses of the rat placenta contain reaction products of nucleoside phosphatases. Fetal blood cells separated from maternal blood by the placental labyrinth show no activity during normal or prolonged gestation. Neonatal blood cells examined 34 hours after parturition show these enzyme activities.
Ribosomes: Analysis by Cesium Sulfate Gradient Centrifugation
Authors: DeFilippes Frank M.
Published: October 2006

Ribosomes from the cytoplasm of a mammalian tissue, HeLa cells, were partially purified and then concentrated into a zone by prolonged centrifugation in Cs
2
SO
4
solution (density, 1.43 grams per milliliter). Ribosomal preparations treated with bentonite prior to density-gradient centrifugation showed single peaks after centrifugation. Material recovered from the peaks represented aggregates of the original 74
S
particle.
Glycerol Metabolism in the Human Liver: Inhibition by Ethanol
Authors: Lundquist Frank , Tygstrup Niels , Winkler Kjeld , Jensen K. Birger
Published: October 2006

Glycerol is metabolized predominantly in the liver, the first step presumably being phosphorylation to α-glycerophosphate. When ethanol is present in the blood the rate of glycerol uptake by the splanchnic organs is reduced to about one-third of the control value. At the same time glycerophosphate accumulates in the liver. Hepatic blood flow and oxygen consumption are not influenced by the combined infusion of glycerol and ethanol. The phenomenon may be connected with the increased concentration of the reduced form of diphosphopyridine nucleotide present in the liver during ethanol metabolism.
Papain Membrane on a Collodion Matrix: Preparation and Enzymic Behavior
Authors: Goldman R. , Silman H. I. , Caplan S. R. , Kedem O. , Katchalski E.
Published: October 2006

A stable papain membrane has been prepared on a collodion matrix by absorbing papain in a collodion membrane and then cross-linking the papain with bisdiazobenzidine 3,3′-disulfonic acid. The
p
H-dependence of the activity of the enzyme membrane on the low-molecular-weight substrate, benzoylarginine ethyl ester, was found to differ from that of crystalline papain; the activity was low in the neutral
p
H range where the native enzyme has its optimum and high at alkaline
p
H. This anomalous behavior is due to a lowering of the local
p
H within the membrane as a result of the release of acid by the enzymic hydrolysis of the ester substrate.
Thunderstorm Electrification and Raindrop Collisions and Disjection in an Electric Field
Authors: Gunn Ross
Published: October 2006

Raindrop collisions in an electric field selectively transfer charges of one sign to the larger disjected drops. The disjected drops, falling away from the smaller drops, separate free charge to establish electric fields as large as those observed in thunderstorms.
Collagen Defect Induced by Penicillamine
Authors: Nimni Marcel E. , Bavetta Lucien A.
Published: October 2006

Collagen synthesis, as judged by the accumulation of collagen in a subcutaneous, induced granuloma, was significantly decreased by penicillamine. Penicillamine also caused a marked increase in the amount of soluble collagen in skin and a sharp drop in insoluble material. These findings, which reflect an abnormal pattern of collagen metabolism, are accompanied by an inhibition of wound-healing and by skin fragility.
Intercrystalline Links in Bulk Polyethylene
Authors: Keith H. D. , Padden F. J. , Vadimsky R. G.
Published: October 2006

Strength-promoting intercrystalline links in polyethylene, crystallized from the melt, have been observed under the electron microscope. The links measure up to many thousands of angstroms in length (depending upon the molecular weight of the polymer) and are of the order of 100 Å in diameter. Their formation appears to be initiated by molecular chains which contact, and begin to crystallize upon, the surfaces of two or more different crystals, often some distance apart. Deposition continues until these molecular bridges are pulled taut. More molecules are laid down upon the bridges to build up the larger links, which are themselves crystalline and may well be extended-chain single crystals.
Oncogenicity of the Simian Adenoviruses
Authors: Hull Robert N. , Johnson Irving S. , Culbertson Clyde G. , Reimer Charles B. , Wright Howard F.
Published: October 2006

Five of 17 adenoviruses of rhesus or cynomolgus monkey origin induced tumors in newborn hamsters. The tumors appeared between 42 and 280 days after subcutaneous inoculation and had the general characteristics of lymphomas. The tumors were specific by cross-complement fixation tests. An adenovirus recovered from
Cercopithecus
monkeys appeared to be highly oncogenic; all 23 inoculated hamsters developed tumors within 30 to 40 days.
Exchangeable Mass: Determination without Assumption of Isotopic Equilibrium
Authors: Bergner Per-Erik E.
Published: October 2006

The method of isotope dilution for determining the exchangeable mass of different substances in living organisms is, at best, approximate. A formally exact method, defining the otherwise vague concept of exchangeable mass, is proposed. The new method may serve as a standard for determining errors in results obtained by the earlier method.
Nitrogen: Formation by Photooxidation of Ethylene in the Presence of Its Oxides
Authors: Bufalini J. J. , Purcell J. C.
Published: October 2006

The apparent lack of nitrogen balance for the photooxidation systems containing olefin and nitrogen oxides can be explained by evidence for the production of molecular nitrogen; molecular nitrogen was identified by gas chromatography and mass spectrometry.
Sea-Level Changes during the Last 2000 Years at Point Barrow, Alaska
Authors: Hume James D.
Published: October 2006

Eustatic rises of sea level between A. D. 265 and 500 and between A. D. 1000 and 1100 caused the formation of raised beaches. After the first rise, sea level dropped about 2 meters below the present level, permitting Eskimo settlement of Birnirk about A. D. 500. The second rise of the ocean flooded Birnirk. At present, sea level is about 0.6 to 1.0 meter below the high-water levels; the ocean partially floods Birnirk.
Electrical Output of Lizard Ear: Relation to Hair-Cell Population
Authors: Wever Ernest Glen , Vernon Jack A. , Crowley David E. , Peterson Ernest A.
Published: October 2006

Cochlear potentials measured in several species of lizard show a close correlation between maximum electrical output and number of hair cells, whereas there is no uniform relation to sensitivity. These results are interpreted as indicating structural differentiation and frequency discrimination in spatial terms in the more advanced lizard ears.
Hearing Sensitivity in Bats
Authors: Dalland John I.
Published: October 2006

Absolute hearing thresholds for two bats were determined by an operant conditioning technique. Pure tones ranging from 2.5 to 100 kilocycles per second were perceived by a single
Eptesicus fuscus
. Its maximum sensitivity was on the order of 68 decibels below 1 dyne per square centimeter and occurred at 20 kc/sec. Maximum sensitivity for a single Myotis lucifugus was about 64 db below 1 dyne/cm
2
and occurred at 40 kc/sec. The Myotis clearly heard a tone of 120 kc/sec but gave no evidence of hearing below 10 kc/sec.
Adenovirus Multiplication: Genetic Relatedness of Tumorigenic Human Adenovirus Types 7, 12, and 18
Authors: Lacy S. , Green Maurice
Published: October 2006

Hybridization measurements among the DNA's of six weakly tumorigenic strains of human adenovirus type 7 reveal that all six strains are very closely related (83- to 110-percent nucleotide sequence homology). The DNA homology between these six type 7 strains and nontumorigenic types 2 and 4 is 32 percent and 52 percent, respectively. The 10- to 20-percent homology between the type 7 DNA's and those of "potent" tumorigenic types 12 and 18 indicates a very low degree of genetic relatedness. These data indicate that, if the carcinogenic potential of adenovirus types 7, 12, and 18 lies in the possession of nucleotide sequences common to these three viruses, these regions represent a small portion of the total genome, approximately one to three viral cistrons.
Retina: Pathology of Neodymium and Ruby Laser Burns
Authors: Wolbarsht M. L. , Fligsten K. E. , Hayes J. R.
Published: October 2006

Chorioretinal lesions have been produced in monkeys during experiments with ruby and neodymium lasers. Most of the energy from the ruby laser (wavelength 6943 angstroms) is absorbed by the pigment epithelium, where the greatest damage appears. With the neodymium laser (10,600 angstroms) the neural portions of the retina absorb more of the energy than the pigment layer does; consequently these portions exhibit more damage than the pigment epithelium and adjacent tissues.