bluuebunny/crossref_metadata_2025 huggingface dataset:
Auditory Nerve: Electrical Stimulation in Man
Authors: Simmons F. Blair , Epley John M. , Lummis Robert C. , Guttman Newman , Frishkopf Lawrence S. , Harmon Leon D. , Zwicker Eberhard
Published: October 2006

Auditory perceptions produced in a person deaf to acoustic stimulation were studied by electrically exciting the auditory nerve through permanently implanted electrodes. Pulsed current as small as 1 microampere peak-to-peak could be perceived. Pitch, as reported by the subject, varied with electrode selection, current amplitude, and pulse repetition rate from about 70 to at least 300 pulses per second. Loudness increased with amplitude and duration of pulse stimuli, and to a lesser extent with repetition rate. The total range in amplitude of the stimulus, from threshold to an uncomfortable loudness, was 15 to 20 decibels. Simultaneous stimulation in separate electrodes produced a number of complex effects.
Wisconsinan Age of the Titusville Till (formerly called "Inner Illinoian"), Northwestern Pennsylvania
Authors: White George W. , Totten Stanley M.
Published: October 2006

Peat discovered below drift near Titusville, Pennsylvania, formerly called "inner Illinoian," has a carbon-14 age of 31,400 ± 2,100 years. The overlying drift, herein named Titusville Till, is therefore not Illinoian but is "late early Wisconsinan" or late Altonian of the Lake Michigan lobe classification.
Lesions in the Medial Forebrain Bundle: Delayed Effects on Sensitivity to Electric Shock
Authors: Harvey John A. , Lints Carlton E.
Published: October 2006

Rats with bilateral lesions in the medial forebrain bundle demonstrate both an increased sensitivity to electric shock, as reflected by a lowered jump threshold, and a decrease in the concentration of serotonin in the brain. Both effects of the lesion are characterized by a delayed time of onset and gradual development, which approximates the time required for progressive nerve degeneration in the central nervous system. It is suggested that this behavioral effect of bilateral lesions in the medial forebrain bundle may be due to a central denervation supersensitivity.
Hemoglobin Heterogeneity: Embryonic Hemoglobin in the Duckling and Its Disappearance in the Adult
Authors: Borgese Thomas A. , Bertles John F.
Published: October 2006

The 7-day white Peking duck embryo contains two hemoglobins (Hb's III and IV) which are electrophoretically distinct from the two adult hemoglobins (Hb's I and II). Hemoglobin IV had disappeared in the 14-day embryo, at which time Hb's I and II are evident. The synthesis of Hb III is not restricted to embryonic life but continues in the duckling and ceases before the 10th week of development after hatching.
Epinephrine-Induced Normalization of Lipid Metabolism in Adrenalectomized Rats
Authors: Friedman Meyer , Byers Sanford O.
Published: October 2006

In adrenalectomized rats given adequate supportive therapy with sodium chloride and hydrocortisone, lipemia is markedly elevated after a triglyceride meal. This defect can be corrected by the administration of epinephrine.
High-Pressure Single-Crystal Studies of Ice VI
Authors: Block S. , Weir C. W. , Piermarini G. J.
Published: October 2006

By means of a precession camera incorporating a diamond-anvil high-pressure cell, x-ray diffraction data can be obtained from single crystals of ice VI produced and maintained under high pressures. The cell constants for ice VI at room temperature and approximately 9 kilobars are:
a
= 8.38 Å,
b
= 6.17 Å,
c
= 8.90 Å. The unit cell is orthogonal and the space-group aspect is compatible with
P
**
a
. These data for single crystals agree with previously reported unindexed data obtained for polycrystalline ice VI, within the limits of experimental error. The single crystals of ice VI were grown in a diamond-anvil pressure cell, distilled water and a metal gasket being used.
Some Kinetic Properties of a Deterministic Epidemic Confirmed by Computer Simulation
Authors: Black Martin L. , Gay Ian D.
Published: October 2006

Representative epidemic transients were generated by computer by a known, plausible mechanism. Accurate retrieval of the individual rate constants and confirmation of their predictive value resulted from a manual test of the mechanism by which the computer outputs were generated. The method is applicable in principle to any regenerative process opposed by exponential decay.
Ethylene Action and the Ripening of Fruits
Authors: Burg Stanley P. , Burg Ellen A.
Published: October 2006

Recent studies employing gas chromatography show that an amount of ethylene large enough to stimulate ripening is always present within a fruit before the respiratory climacteric begins. This fact and data from experiments in which fruits were exposed to a partial vacuum or varying concentrations of O
2
, CO
2
, and ethylene oxide reinforces the view that ethylene is a ripening hormone. The respiratory climacteric begins soon after the fruit is harvested because the tissue no longer receives from the shoot system a substance which inhibits ripening; this substance may act by lowering the sensitivity of the fruit to ethylene. The threshold for ethylene action is also influenced by the composition of the atmosphere, for O
2
is a substrate in the reaction activated by ethylene and CO
2
inhibits the action of ethylene by competing with the olefin for the receptor site. Experiments indicate that ethylene is derived from acetate or acids of the Krebs cycle and acts by binding to a metal receptor site in the tissue.
Neurons of Insects: RNA Changes during Injury and Regeneration
Authors: Cohen Melvin J. , Jacklet Jon W.
Published: October 2006

A dense concentration of RNA appears in the perinuclear cytoplasm of nerve cell bodies in the third thoracic ganglion of the cockroach within 12 hours after their axons are cut. The basiphilic material of the perinuclear ring reaches maximum development 2 to 3 days after axon injury and returns to normal at about 15 days. Ribonuclease removes the basiphilic material, indicating that it is RNA. The perinuclear ring of RNA provides a marker for linking an individual central nerve cell body to a particular peripheral axon and the muscle it innervates.
Sector Structure of the Quiet Interplanetary Magnetic Field
Authors: Ness Norman F. , Wilcox John M.
Published: October 2006

Observations of the interplanetary magnetic field by the Imp-1 satellite have revealed a regular longitudinal sector structure in this field. The sectors co-rotate with the sun; as an average sector sweeps past the earth the magnitude of the interplanetary field decreases from greater than 6 gammas (1 gamma = 10
-5
gauss) to less than 4 gammas, and the daily sum of the geomagnetic activity index,
Kp
decreases from 25 to less than 10.
Tectonic Deformation Associated with the 1964 Alaska Earthquake
Authors: Plafker George
Published: October 2006

Alaska's Good Friday earthquake of 27 March 1964 was accompanied by vertical tectonic deformation over an area of 170,000 to 200,000 square kilometers in south-central Alaska. The deformation included two major northeast-trending zones of uplift and subsidence situated between the Aleutian Trench and the Aleutian Volcanic Arc; together they are 700 to 800 kilometers long and from 150 to 250 kilometers wide. The seaward zone is one in which uplift of as much as 10 meters on land and 15 meters on the sea floor has occurred as a result of both crustal warping and local faulting. Submarine uplift within this zone generated a train of seismic sea waves with half-wave amplitudes of more than 7 meters along the coast near the source. The adjacent zone to the northwest is one of subsidence that averages about 1 meter and attains a measured maximum of 2.3 meters. A second zone of slight uplift may exist along all or part of the Aleutian and Alaska ranges northwest of the zone of subsidence.
Infrared Spectra as a Means of Determining Botanical Sources of Amber
Authors: Langenheim Jean H. , Beck Curt W.
Published: October 2006

Comparison of infrared spectra of amber no older than Oligo-Miocene with present-day resins provides convincing evidence as to source, especially with corroboration from paleobotanical remains and knowledge of living resin producers. Spectroscopy is also useful in establishing that amber in widely separated areas in the Cretaceous and Eocene is from the same botanical source, although it may not be possible to relate these older resins to those from present-day plant populations.
Stimulus Variables Determining Space Perception in Infants
Authors: Bower T. G. R.
Published: October 2006

It was shown previously that infants who have neither reached nor crawled discriminate changes in spatial position on the basis of cues other than the projective size of objects displaced in space. It is now shown that binocular vision is not necessary for discrimination and that pictorial cues are not sufficient for discrimination. Parallax variables provide the information used by such infants for the discrimination of size and distance.
Adult Thymectomy: Effect on Recovery from Immunologic Depression in Mice
Authors: Monaco Anthony P. , Wood Mary L. , Russell Paul S.
Published: October 2006

A/Jax mice treated for 1 week with rabbit antiserum to A/Jax lymphocytes showed peripheral lymphopenia and tissue lymphocyte depletion which persisted for 4 weeks after initiation of serum treatment. During this time, such animals showed depression of the humoral antibody response and inability to reject skin allografts. After 4 weeks, mice recovered from effects of serum treatment. Normal blood and tissue lymphocyte levels returned, and immunologic competence was restored. Thymectomy of A/Jax mice (8 to 10 weeks old) prior to serum treatment resulted in peripheral and tissue lymphopenia and depression of antibody formation, which persisted twice as long as that shown by animals given serum alone. Similarly, skin allografts survive two to four times longer in serum-treated thymectomized mice, and, in some cases, persisted over 100 days in perfect condition.
Visual Resolution and the Diffraction Limit
Authors: Barlow H. B.
Published: October 2006

Movement of a grating behind a fixed aperture can be detected by human subjects when the grating is well below the diffraction limit of the pupil and below acuity measured with stationary gratings. With movement one sees a flicker or ripple at the edges, and it is argued that these edge effects lead to spurious estimates of optical resolution in insects and man.
Rhythmic Enzyme Changes in Neurons and Glia during Sleep
Authors: Hyden H. , Lange P. W.
Published: October 2006

Rhythmic changes occur in the activities of enzymes in both the neurons and neuroglia isolated from the caudal part of the reticular formation of rabbits killed during sleep and wakefulness. During sleep, enzyme activity is high in the neurons and low in the glia; during wakefulness, this situation is reversed. In the oral part of the reticular formation rhythmic enzyme changes occur only in the neurons. No rhythmic changes occur in the hypoglossal and trigeminal mesencephalic neurons and glia. These findings indicate that the caudal part of the reticular formation reflects in metabolic changes the biological clock behind the sleep rhythm.
Trend Curves of the Rate of Species Description in Zoology
Authors: Steyskal George C.
Published: October 2006

Trend charts of approximately 0.4 percent of the animal kingdom indicate that the describing and naming of species, "alpha taxonomy," is far from completed.
Mechanistic Aspects of Signaling Through Ras in NIH 3T3 Cells
Authors: Zhang Ke , Papageorge Alex G. , Lowy Douglas R.
Published: October 2006

Serum and growth factors can increase the proportion of Ras in the active guanosine triphosphate (GTP)-bound form. Growth factors might stimulate guanine nucleotide exchange or decrease the activity of the guanosine triphosphatase-activating proteins GAP and neurofibromin (NF1). In NIH 3T3 cells that overexpress the mutant Ras protein His
116
, which releases bound guanine nucleotide at a constitutively high rate and retains sensitivity to GAP and NF1, the proportion of GTP bound to the His
116
protein was not altered by serum or platelet-derived growth factor. However, these mitogens increased the proportion of Ras in the GTP-bound form in cells that overexpressed control Ras proteins with a normal intrinsic rate of guanine nucleotide release. The amount of GTP-bound His
116
or control Ras proteins was higher in cells at low density than in cells at high density, which have more GAP-like activity. The lower proportion of GTP-bound Ras in NIH 3T3 cells at high density may result from increased GAP-like activity. By contrast, serum and platelet-derived growth factors appear to stimulate guanine nucleotide exchange.
Hypovirulence of Chestnut Blight Fungus Conferred by an Infectious Viral cDNA
Authors: Choi Gil H. , Nuss Donald L.
Published: October 2006

Strains of the chestnut blight fungus
Cryphonectria parasitica
that contain viral double-stranded RNAs often exhibit reduced virulence. Such hypovirulent strains act as biocontrol agents by virtue of their ability to convert virulent strains to hypovirulence after anastomosis. Transformation of virulent
C. parasitica
strains with a full-length complementary DNA copy of a hypovirulence-associated viral RNA conferred the complete hypovirulence phenotype. Cytoplasmic double-stranded RNA was resurrected from the chromosomally integrated complementary DNA copy and was able to convert compatible virulent strains to hypovirulence. These results establish viral double-stranded RNA as the causal agent of hypovirulence and demonstrate the feasibility of engineering hypovirulent fungal strains.
Glide Mechanisms in Experimentally Deformed Minerals
Authors: Raleigh C. B.
Published: October 2006

A method for study of mechanisms of twin and translation gliding in minerals in rocks has been devised by which slip markings produced experimentally on polished surfaces are related to crystallographic planes by universal stage measurements of the crystal orientations. In specimens strained 5 to 10 percent at 5 to 7 kilobars confining pressure and 700° to 850°C, the glide plane and glide direction for slip and twinning have been determined in olivine, enstatite, kyanite, and diopside. Slip occurs in closest-packed directions, in which also lies the shortest Burgers vector of a unit edge dislocation in the slip plane.
Visual Excitation and Blood Clotting
Authors: Wald George
Published: October 2006

Both processes involve extremely large amplification between the stimulus and the response. In vision it had been suggested that this might be achieved by a chain of successive proenzyme-enzyme activations. Such a chain has now been found to underlie the mechanism of blood clotting. Methods are suggested for pursuing this comparison further.
Strontium Isotopes: Global Circulation after the Chinese Nuclear Explosion of 14 May 1965
Authors: Kuroda P. K. , Miyake Y. , Nemoto J.
Published: October 2006

Strontium-89 and strontium-90, released into the atmosphere by the Chinese nuclear device on 14 May 1965, circled the world in less than a month and caused a sharp peak in the Sr
89
/Sr
90
ratio in rain at Tokyo on 12 June.
X-Linked 6-Phosphogluconate Dehydrogenase in
Drosophila
: Subunit Associations
Authors: Kazazian H. H. , Young W. J. , Childs B.
Published: October 2006

6-Phosphogluconate dehydrogenase (PGD) subunits have been dissociated and reassociated in vitro. The intermediate PGD of the heterozygous phenotype is reproduced by reassociation in vitro of subunits derived from the two types of PGD from homozygous flies. This result has a bearing on gene action in the diploid organism and on the mechanism of dosage compensation in
Drosophila melanogaster
.
Theory of Rotation for the Planet Mercury
Authors: Liu Han-Shou , O'Keefe John A.
Published: October 2006

The theory of the rotation of the planet Mercury is developed in terms of the motion of a rigid system in an inverse-square field. It is possible for Mercury to rotate with a period exactly two-thirds of the period of revolution; there is a libration with a period of 25 years.
Beta-Solamarine: Tumor Inhibitor Isolated from
Solanum dulcamara
Authors: Kupchan S. Morris , Barboutis Stanley J. , Knox John R. , Lau Cam Cesar A.
Published: October 2006

An alcoholic extract of
Solanum dulcamara
L., a plant widely used in folk medicine for treating cancers and warts, shows tumor-inhibitory activity against Sarcoma 180 in mice. Systematic fractionation of the extract has led to isolation and characterization of β-solamarine as an active principle.
Sex Chromatin of Cone Cells of Human Retina
Authors: Teplitz Raymond L.
Published: October 2006

Each retinal cone cell of the female contains a sex-chromatin body not present in comparable material from the male. Therefore the lack of detectable "patch" formation in female heterozygotes for red color-blindness (as expected from the X-inactivation hypothesis) cannot be attributed to failure of Barr-body formation.
Internal Stark Effect Measurement of the Electric Field at the Amino Terminus of an α Helix
Authors: Lockhart David J. , Kim Peter S.
Published: October 2006

The strengths of electrostatic interactions in biological molecules are difficult to calculate or predict because they occur in complicated, inhomogeneous environments. The electric field at the amino terminus of an α helix in water has been determined by measuring the shift in the absorption band for a covalently attached, neutral probe molecule with an electric dipole moment difference between the ground and excited electronic states (an internal Stark effect). The field at the interface between the helix and the solvent is found to be an order of magnitude stronger than expected from the dielectric properties of bulk water. Furthermore, although the total electric dipole moment of the helix increases with length, the electric field at the amino terminus does not.
Sorbitol Pathway: Presence in Nerve and Cord with Substrate Accumulation in Diabetes
Authors: Gabbay Kenneth H. , Merola Lorenzo O. , Field Richard A.
Published: October 2006

Glucose, sorbitol, fructose, and inositol are present in peripheral nerve and spinal cord. Marked elevation of these substances occurs in these tissues in mildly diabetic animals. These alterations provide biochemical mechanisms which could be significant in the etiology of diabetic neuropathy.
Fatty Change of the Granular Pneumocyte
Authors: Valdivia Enrique , Sonnad Jayashree , D'Amato James
Published: October 2006

Fat vacuoles develop in the granular pneumocytes of guinea pigs exposed to severe hypoxia in low-pressure chambers. The osmiophilic lamellar bodies are apparently reduced in size and decreased in number. The fatty change of the granular pneumocyte may represent a metabolic alteration and interfere with the production of surfactant. This hypoxic lesion of the pneumocyte may be a significant factor in high-altitude pulmonary insufficiency.
Tabashir: An Opal of Plant Origin
Authors: Jones L. H. P. , Milne A. A. , Sanders J. V.
Published: October 2006

A specimen of tabashir, a variety of opal found in bamboo, contained more water but smaller amounts of alkalis and alkaline earths than most opals. It consisted of particles of about 100 angstroms in diameter, linked together in clumps, which appeared in fractured surfaces as irregularities. The tabashir was amorphous, but its microstructure differed from that of silica gel and amorphous opal of inorganic origin.
Thunderstorm Electrification of Hail and Graupel by Polar Dribble
Authors: Gunn Ross
Published: October 2006

Hail and graupel falling through rain collect water that selectively dribbles upward from the upper surface of a hailstone. When the hailstones are polarized by nearly vertical electrostatic field these vertically discharged water drops carry away free charge of the same sign as that induced on the upper surfaces. The hail thereby accumulates an equilibrium charge of opposite sign, corresponding to the charges induced on the bottom surfaces. The equilibrium charges are large enough to be important in thunderstorms.
Virus Induction of Osteosarcomas in Mice
Authors: Finkel Miriam P. , Biskis Birute O. , Jinkins Patricia B.
Published: October 2006

A virus extracted from an osteosarcoma of a mouse produces similar tumors when injected into newborn mice. The original tumor appeared spontaneously in an untreated CFI male. The time between inoculation with virus and detection of bone sarcoma has been as short as 23 days.
Tertiary Sediment from the Mid-Atlantic Ridge
Authors: Saito Tsunemasa , Ewing Maurice , Burckle Lloyd H.
Published: October 2006

Lower Miocene microfossils occur in basaltic glass in two dredge hauls from the crestal area of the Mid-Atlantic Ridge near 30°N. From the ridge and adjoining abyssal hills 43 pre-Pleistocene cores were identified, including one Cretaceous and four Eocene. Dredgings and cores now available suggest that the upper layer of the crust of the ridge is constructed of layers of interbedded sediments and basalt flows. The data rule out the possibility of large-scale continental drifting or spreading of the ocean floor since the Lower Miocene.
Osteolytic Sterol in Human Breast Cancer
Authors: Gordan Gilbert S. , Cantino Theodore J. , Erhardt Linda , Hansen James , Lubich Warren
Published: October 2006

Eleven of twelve human breast cancers contained a lipid which increased urinary
45
Ca and
40
Ca excretion of
45
Ca-labeled, parathyroidectomized rats receiving a low Ca diet. The lipid has mobility on thin-layer chromatography and gas-liquid chromatography close to, but not identical with, that of 7-dehydrocholesterol. Authentic 7-dehydrocholesterol has osteolytic activity similar to that of the extracted sterol. Fluorescence and Lieberman-Burchard reactions of the extracted sterol are similar to those of 7-dehydrocholesterol. The lipid was found by thin-layer chromatography in the extracts which had osteolytic activity. Neither the lipid nor osteolytic activity was found in extracts of tissue from two normal human breasts.
Immunological Competence: Alteration by Whole Body X-Irradiation and Shielding of Selected Lymphoid Tissues
Authors: Miller Joshua
Published: October 2006

The spleen and thymus of 6-week-old mice contain similar numbers of lymphoid cells. A lethal dose of x-irradiation given to animals whose thymus, midgut, or hindlimbs were shielded at the same time resulted in permanent acceptance of allografts, while a similar dose given to spleen-shielded mice so irradiated resulted in a normal rejection pattern. The return of immunological competence was related to the state of the lymphoid organs with different types of shielding.
SV2, a Brain Synaptic Vesicle Protein Homologous to Bacterial Transporters
Authors: Bajjalieh Sandra M. , Peterson Karen , Shinghal Rajesh , Scheller Richard H.
Published: October 2006

Synaptic vesicle protein 2 (SV2) is a membrane glycoprotein specifically localized to secretory vesicles in neurons and endocrine cells. As a first step toward understanding the function of SV2 in neural secretion, a rat brain complementary DNA (cDNA) that encodes SV2 was isolated and characterized. Analyses of this cDNA predict that SV2 contains 12 transmembrane domains. The NH
2
-terminal half of the protein shows significant amino acid sequence identity to a family of bacterial proteins that transport sugars, citrate, and drugs. Expression of the SV2 cDNA in COS cells yielded a high level of SV2-like immunoreactivity distributed in a reticular and punctate pattern, which suggests localization to intracellular membranes. Its localization to vesicles, predicted membrane topology, and sequence identity to known transporters suggest that SV2 is a synaptic vesicle-specific transporter.
Evolution of the Structure of Ferredoxin Based on Living Relics of Primitive Amino Acid Sequences
Authors: Eck Richard V. , Dayhoff Margaret O.
Published: October 2006

The structure of present-day ferredoxin, with its simple, inorganic active site and its functions basic to photon-energy utilization, suggests the incorporation of its prototype into metabolism very early during biochemical evolution, even before complex proteins and the complete modern genetic code existed. The information in the amino acid sequence of ferredoxin enables us to propose a detailed reconstruction of its evolutionary history. Ferredoxin has evolved by doubling a shorter protein, which may have contained only eight of the simplest amino acids. This shorter ancestor in turn developed from a repeating sequence of the amino acids alanine, aspartic acid or proline, serine, and glycine. We explain the persistence of living relics of this primordial structure by invoking a conservative principle in evolutionary biochemistry: The processes of natural selection severely inhibit any change in a well-adapted system on which several other essential components depend.
Trace Element Partition Coefficient in Ionic Crystals
Authors: Nagasawa Hiroshi
Published: October 2006

Partition coefficients of monovalent trace ions between liquids and either solid NaNO
3
or KCl were determined. The isotropic elastic model of ionic crystals was used for calculating the energy change caused by the ionic substitutions. The observed values of partition coefficients in KCl are in good agreement with calculated values.
Electroencephalographic Activation: Nonspecific Habituation by Verbal Stimuli
Authors: Mulholland Thomas , Davis Edward
Published: October 2006

A decrease in the duration of the electroencephalographic activation response to a series of different words: emotional, "neutral," and scrambled occurred. The response to "neutral" words was consistently briefer than that to the other words. This result is evidence of a nonspecific habituation of activation, which implies that habituation to classes of stimuli can occur.
Radioactivity of the Lunar Surface
Authors: Kraner Hobart W. , Schroeder Gerald L. , Davidson Gilbert , Carpenter Jack W.
Published: October 2006

Diffusion of radon and thoron from the lunar surface provides a mechanism for production of a radioactive surface layer on the moon. If the radon and thoron flux from the lunar surface is equal to that measured at the earth's surface, the equilibrium activity of this surface layer is estimated as approximately 1 microcurie per square meter, due to radon and its decay products. This activity consists of alpha particles and gamma rays at well-defined energies and of beta rays.
Epinephrine: Cascade Reactions and Glycogenolytic Effect
Authors: Bowness J. M.
Published: October 2006

The concept of a cascade reaction may serve to indicate the underlying chemical similarity between several biological amplification processes, and as a basis for the formulation of units that emphasize amplification phenomena in reaction kinetics. This approach is discussed in relation to the glycogenolytic effect of epinephrine.
Heart Rate: Changes during Conditioned Suppression in Rats
Authors: de Toledo Leyla , Black A. H.
Published: October 2006

Heart rate of rats was recorded in the Estes-Skinner conditioned emotional response situation. Response to the conditioned stimulus was a decrease in rate. The change in heart rate was conditioned more slowly than suppression of bar-pressing; it was of shorter duration and was more variable than suppression.
Tritiated Norepinephrine: Release from Brain Slices by Electrical Stimulation
Authors: Baldessarini Ross J. , Kopin Irwin J.
Published: October 2006

Slices of rat brain and heart that had concentrated H
3
-norepinephrine were superfused and electrically stimulated. Stimulation induced a marked release of H
3
-norepinephrine with a threshold and a maximum response. Release also occurred with increased concentrations of potassium, presumably due to neuronal depolarization. Inhibition of electrically induced release occurred with low calcium and with chlorpromazine and pentobarbital.
Survival of Mammals Breathing Organic Liquids Equilibrated with Oxygen at Atmospheric Pressure
Authors: Clark Leland C. , Gollan Frank
Published: October 2006

Because oxygen and carbon dioxide are very soluble in certain silicone oils and fluorocarbon liquids, these liquids will support respiration of mammals. Mice and cats respiring silicone oil die shortly after return to air breathing, while those breathing fluorocarbon survive for weeks. The respiration of mice is optimally supported by these organic liquids at about 20°C. In cats, arterial oxygenation is excellent, but there is some impairment of carbon dioxide elimination. All animals have suffered some pulmonary damage from breathing fluorocarbon liquids. Continued investigation of organic fluid respiration may lead to development of a safe method to support the respiration of man by liquids equilibrated with gases at atmospheric pressure.
Oligomerization of Ribonucleotides on Montmorillonite: Reaction of the 5′-Phosphorimidazolide of Adenosine
Authors: Ferris James P. , Ertem Gözen
Published: October 2006

The regiospecific formation of oligomers from unblocked monomers in aqueous solution is one of the central tenets in research on the origins of life on earth. Direct experimental support for this hypothesis has been obtained in studies of the condensation of the 5′-phosphorimidazolide of adenosine (ImpA) with itself and with P
1
,P
2
-diadenosine-5′,5′-pyrophosphate (AppA) in water in the presence of a montmorillonite clay. Oligomers of up to ten nucleotides in length are formed. Analysis of the trimers, tetramers, and pentamers formed from a 9:1 ImpA:AppA mixture has shown that 85% of the bonds formed are 3′,5′-linked and that any 2′,5′-linkages present are at the phosphodiester bond next to the 3′-terminus of the oligomers.
Cloning of the 62-Kilodalton Component of Basic Transcription Factor BTF2
Authors: Fischer Laurent , Gerard Matthieu , Chalut Christian , Lutz Yves , Humbert Sandrine , Kanno Masamoto , Chambon Pierre , Egly Jean-Marc
Published: October 2006

Cloning of the mammalian basic transcription factors serves as a major step in understanding the mechanism of transcription initiation. The 62-kilodalton component (p62) of one of these transcription factors, BTF2 was cloned and overexpressed. A monoclonal antibody to this polypeptide inhibited transcription in vitro. Immunoaffinity experiments demonstrated that the 62-kilodalton component is closely associated with the other polypeptides present in the BTF2 factor. Sequence similarity suggests that BTF2 may be the human counterpart of RNA polymerase II initiation factor b from yeast.
Myotonic Response Induced by Inhibitors of Cholesterol Biosynthesis
Authors: Winer Nathaniel , Klachko David M. , Baer Robert D. , Langley Paul L. , Burns Thomas W.
Published: October 2006

Steroid inhibitors of cholesterogenesis containing nitrogen-substituted side chains induced electromyographic myotonia in rats. Cholesterol reduction or desmosterol accumulation, per se, did not cause myotonia, and cholesterol feeding prevented drug-induced myotonia. Desmosterol accumulation in combination with a specific drug effect may cause the observed myotonia.
Lemur Social Behavior and Primate Intelligence
Authors: Jolly Alison
Published: October 2006

Our human intellect has resulted from an enormous leap in capacity above the level of monkeys and apes. Earlier, though, Old and New World monkeys' intelligence outdistanced that of other mammals, including the prosimian primates. This first great advance in intelligence probably was selected through interspecific competition on the large continents. However, even at this early stage, primate social life provided the evolutionary context of primate intelligence.

Two arguments support this conclusion. One is ontogenetic: modern monkeys learn so much of their social behavior, and learn their behavior toward food and toward other species through social example. The second is phylogenetic: some prosimians, the social lemurs, have evolved the usual primate type of society and social learning without the capacity to manipulate objects as monkeys do. It thus seems likely that the rudiments of primate society preceded the growth of primate intelligence, made it possible, and determined its nature.
Inorganic Pyrophosphate: Formation in Bacterial Photophosphorylation
Authors: Baltscheffsky Herrick , von Stedingk Lars-Victor , Heldt Hans-Walter , Klingenberg Martin
Published: October 2006

Inorganic pyrophosphate is identified as the major product of photophosphorylation by isolated chromatophores from
Rhodospirillum rubrum
in the absence of added nucleotides.
Methylene-C
14
-Dioxyphenyl Compounds: Metabolism in Relation to Their Synergistic Action
Authors: Casida John E. , Engel Judith L. , Essac Essac G. , Kamienski Francis X. , Kuwatsuka Shozo
Published: October 2006

The methylene-C
14
group is hydroxylated yielding formate-C
14
in the microsome-reduced nicotinamide-adenine dinucleotide phosphate system in vitro and yielding expired C
14
O
2
, in living mice and houseflies. Methylenedioxyphenyl compounds apparently serve as alternate substrates for this enzymatic hydroxylation system of microsomes, and thus reduce the rate of metabolism and prolong the action of certain drugs and insecticide chemicals.
Strontium Incorporation into Dental Enamel
Authors: Johnson A. R. , Armstrong W. D. , Singer Leon
Published: October 2006

Rats were raised on diets either rich or poor in strontium. Powder x-ray diffraction patterns suggest that isomorphous substitution of strontium for calcium occurs in the apatite of tooth enamel, and that strontium may form Sr
6
H
3
(PO
4
) ⋅ 2H
2
O, a compound hitherto unreported in biologic systems.
Radio Rotation Period of Jupiter
Authors: Gulkis Samuel , Carr Thomas D.
Published: October 2006

The results of observations of Jupiter at 18 megacycles per second indicate that the apparent rotation period drifts cyclically about a constant mean value. The most probable drift period appears to be 11.9 years, Jupiter's orbital period. The mean rotation period during one orbital period is about 0.3 second longer than that of the system III (1957.0) period. This is in close agreement with the rotation period deduced from decimetric observations and probably represents the true rotation period of the magnetic field. The cyclic drift in the rotation period of source A at 18 megacycles per second is explained on the basis of beaming of the escaping radiation at an angle 6 degrees north of the magnetic equator. The apparent rotation period of source A depends on the rate of change of the Jovicentric declination of Earth.
Coordinate Synthesis of Heme and Apoenzyme in the Formation of Tryptophan Pyrrolase
Authors: Marver Harvey S. , Tschudy Donald P. , Perlroth Mark G. , Collins Annie
Published: October 2006

Reciprocal control mechanisms between hemoprotein and δ-aminolevulinic acid synthetase take part in coordinate synthesis of the heme and apoenzyme moieties of tryptophan pyrrolase. Stimulation of heme biosynthesis increases tryptophan pyrrolase, whereas enhancement of heme binding by apotryptophan pyrrolase secondarily increases the formation of δ-aminolevulinic acid synthetase, the rate-limiting enzyme in heme formation. Tryptophan-mediated induction of δ-aminolevulinic acid synthetase suggests that heme participates in repression of that enzyme.
Deep-Sea Iron Deposit from the South Pacific
Authors: Bonatti Enrico , Joensuu Oiva
Published: October 2006

Along with specimens of manganese oxides and basalt, rocks containing more than 30 percent iron by weight and consisting mainly of poorly crystallized goethite have been dredged from the flanks of a seamount located on the East Pacific Rise. The Fe-Mn ratio varies widely among the various oxide rocks deposited at this locality and at another seamount in the same area. The deposit was probably formed by fractional precipitation of iron and manganese which had been introduced locally into the bottom water by hydrothermal solutions of volcanic origin, and by leaching from deep-sea basaltic lavas.
Phanerozoic-Cryptozoic and Related Transitions: New Evidence
Authors: Cloud Preston E. , Nelson C. A.
Published: October 2006

The fossil
Pteridinium
, a distinctive component of a worldwide early metazoan (Ediacaran) assemblage, is provisionally recorded from probable early Cambrian strata in eastern California. In context with other evidence, this finding implies a Cambrian age for the Ediacaran fauna and approximate coincidence of limits between Phanerozoic-Cryptozoic, Paleozoic-Precambrian, and Cambrian-Precambrian.
Growth-Rings of Trees: Their Correlation with Climate
Authors: Fritts Harold C.
Published: October 2006

Many differences in the ring-width growth within a tree may be attributed to changing supplies of food and hormones. In moist sites or during periods of favorable climate, there may be sufficient food for the production of wide rings throughout the tree. But in dry sites or during years of low moisture and high temperatures, food competition within the tree is likely to be greater and the cambium at the base of the stem is likely to receive a limited food supply and may produce narrow rings. The cambium at the stem base depends upon the entire crown for food, hence ring growth reflects the tree's ambient climate. But, the cambium in the top of the tree or in the upper branches depends upon a more restricted portion of the crown for its food and hormone supplies. The rings produced by the cambium vary greatly from branch to branch and are less reliable indicators of the climate surrounding the entire tree than rings at the tree base. Therefore, ring series at the base of trees in semiarid sites provide the most reliable, as well as the longest, record of macroclimatic variation.

Tree-ring widths in certain coniferous species growing in semiarid sites appear to represent the integrated effect of climate on food-making and food accumulation in the crown throughout the 14 to 15 months previous to and including the period of growth. Trees in warm, low-elevation sites may utilize winter moisture most efficiently; trees in cool, high-elevation or more northern sites may utilize early summer and early autumn moisture most efficiently. But even with these differences, a significant amount of variance is found to be common among tree-ring series from a wide range of sites, species, and geographical areas in western North America, emphasizing a common dependence of ring widths on the gross regional patterns of precipitation and temperature. The remaining variance, which is not correlated among sites, may be attributed to local environmental and climatic differences, to variability among and within trees, and to compounding effects of occasional fires, insect or other infestations, and recurring years of high seed production.

It is evident that a large portion of the variability in ring-width patterns from semiarid sites in western North America does reflect differences in climate from year to year. If ring chronologies are derived from a number of trees in semiarid sites and if adequate corrections for age and trend are made, these chronologies may be used to reconstruct a first approximation of annual, or somewhat longer period, climatic fluctuations in the past.
Germination of Witchweed (
Striga lutea
Lour.): Isolation and Properties of a Potent Stimulant
Authors: Cook C. E. , Whichard Leona P. , Turner Beverly , Wall Monroe E. , Egley Grant H.
Published: October 2006

A crystalline germination stimulant (trivial name strigol) for the root parasite, witchweed (
Striga lutea
Lour.), has been isolated from cotton root exudates and characterized as a C
19
H
22
O
6
compound. Although apparently different from known plant hormones, the stimulant is active at hormonal levels, causing germination at concentrations less than 10
-5
part per million.
Deep-Sea
p
H
Authors: Park Kilho
Published: October 2006

In the northeastern Pacific Ocean, north of 22°N and east of 180°W, a deep-sea
p
H maximum of 7.9 exists near 4000 meters. The effect of hydrostatic pressure on the dissociation constants of carbonic acid in sea water appears to be important in its formation.
Polypeptide Chains of Immunoglobulins from the Smooth Dogfish (
Mustelus canis
)
Authors: Marchalonis J. , Edelman G. M.
Published: October 2006

The 17
S
and 7
S
immunoglobulins of the smooth dogfish, Mustelus canis, have been characterized with respect to molecular weights, chain structure, amino acid composition, and carbohydrate content. The 17
S
protein had a molecular weight of 982,000; that of the 7
S
protein was 198,000. Both proteins had similar amino acid compositions and a carbohydrate content of approximately 8 percent. Light and heavy chains from both immunoglobulins had molecular weights of 20,000 and 72,000 respectively. Apparently both immunoglobulins belong to the same class; this class resembles the γM-immunoglobulins of higher vertebrates.
Reproduction in Lizards: Influence of Temperature on Photoperiodism in Testicular Recrudescence
Authors: Licht Paul
Published: October 2006

The photoperiodic response of the testis in
Anolis carolinensis
is very temperature-sensitive. Body temperatures must be elevated to near preferred levels (about 32°C) during at least part of the daily light period for long day-lengths to be effective in stimulating testicular recrudescence. High temperatures during the night, with cool days (20°C), may retard testicular growth more than do continuously low temperatures.
Suppression of Gene Amplification in Human Cell Hybrids
Authors: Tlsty Thea D. , White Alicia , Sanchez Janet
Published: October 2006

Gene amplification, one example of genetic instability, is of prognostic and clinical importance in neoplasia. In tumorigenic cells, gene amplification occurs at a very high frequency, whereas in normal diploid fibroblasts the event is undetectable by the clonogenic assay. To investigate genetic control of gene amplification, amplification frequency was measured in hybrids of tumorigenic cells and normal diploid cells. The ability to amplify an endogenous gene behaved as a recessive genetic trait, and control of gene amplification potential segregated independently of tumorigenicity and immortality.
A Human Gene Responsible for Zellweger Syndrome That Affects Peroxisome Assembly
Authors: Shimozawa Nobuyuki , Tsukamoto Toshiro , Suzuki Yasuyuki , Orii Tadao , Shirayoshi Yasuaki , Mori Takeshi , Fujiki Yukio
Published: October 2006

The primary defect arising from Zellweger syndrome appears to be linked to impaired assembly of peroxisomes. A human complementary DNA has been cloned that complements the disease's symptoms (including defective peroxisome assembly) in fibroblasts from a patient with Zellweger syndrome. The cause of the syndrome in this patient was a point mutation that resulted in the premature termination of peroxisome assembly factor-1. The homozygous patient apparently inherited the mutation from her parents, each of whom was heterozygous for that mutation.
Selective Transmission of Human Immunodeficiency Virus Type-1 Variants from Mothers to Infants
Authors: Wolinsky Steven M. , Wike Carla M. , Korber Betre T. M. , Hutto Cecelia , Parks Wade P. , Rosenblum Lisa L. , Kunstman Kevin J. , Furtado Manohar R. , Muñoz José L.
Published: October 2006

Multiple human immunodeficiency virus type-1 sequences from the V3 and V4-V5 regions of the envelope gene were analyzed from three mother-infant pairs. The infants' viral sequences were less diverse than those of their mothers. In two pairs, a proviral form infrequently found in the mother predominated in her infant. A conserved N-linked glycosylation site within the V3 region, present in each mother's sequence set, was absent in all of the infants' sequence sets. These findings demonstrate that a minor subset of maternal virus is transmitted to the infant.
The Linguistic Basis of Left Hemisphere Specialization
Authors: Corina David P. , Vaid Jyotsna , Bellugi Ursula
Published: October 2006

In humans the two cerebral hemispheres of the brain are functionally specialized with the left hemisphere predominantly mediating language skills. The basis of this lateralization has been proposed to be differential localization of the linguistic, the motoric, or the symbolic properties of language. To distinguish among these possibilities, lateralization of spoken language, signed language, and nonlinguistic gesture have been compared in deaf and hearing individuals. This analysis, plus additional clinical findings, support a linguistic basis of left hemisphere specialization.
Atomic Structure of the Cubic Core of the Pyruvate Dehydrogenase Multienzyme Eomplex
Authors: Mattevi Andrea , Obmolova Galya , Schulze Egbert , Kalk Kor H. , Westphal Adrie H. , de Kok Arie , Hol Wim G. J.
Published: October 2006

The highly symmetric pyruvate dehydrogenase multienzyme complexes have molecular masses ranging from 5 to 10 million daltons. They consist of numerous copies of three different enzymes: pyruvate dehydrogenase, dihydrolipoyl transacetylase, and lipoamide dehydrogenase. The three-dimensional crystal structure of the catalytic domain of
Azotobacter vinelandii
dihydrolipoyl transacetylase has been determined at 2.6 angstrom (Å) resolution. Eight trimers assemble as a hollow truncated cube with an edge of 125 Å, forming the core of the multienzyme complex. Coenzyme A must enter the 29 Å long active site channel from the inside of the cube, and lipoamide must enter from the outside. The trimer of the catalytic domain of dihydrolipoyl transacetylase has a topology identical to chloramphenicol acetyl transferase. The atomic structure of the 24-subunit cubic core provides a framework for understanding all pyruvate dehydrogenase and related multienzyme complexes.
Electrophysiologic Studies during Scanning and Passive Eye Movements in Humans
Authors: Scott Donald F. , Bickford Reginald G.
Published: October 2006

It has been demonstrated in man that mechanically induced shifts of the retinal image without change in total luminous flux evoke a parieto-occipital electrical response (lambda waves). The technique provides a simple method of quantifying responses in the visual system without complication by voluntary movements and their associated readiness potentials. The observation contradicts the view that lambda waves are directly concerned with mechanisms preventing blur during eye movement.
Temporary Abolition of Pain in Man
Authors: Wall Patrick D. , Sweet William H.
Published: October 2006

In eight patients with intense chronic cutaneous pain, sensory nerves or roots. supplying the painful area were stimulated. Square-wave 0.1-millisecond pulses at 100 cycles per second were applied, and the voltage was raised until the patient reported tingling in the area. During this stimulation, pressure on previously sensitive areas failed to evoke pain. Four patients, who had diseases of their peripheral nerves, experienced relief of their pain for more than half an hour after stimulation for 2 minutes.
Psilocybin: Reaction with a Fraction of Rat Brain
Authors: Gilmour L. P. , O'Brien R. D.
Published: October 2006

Psilocybin, a hallucinogen, formed a blue color with a subfraction of rat-brain mitochondria believed to contain nerve-ending particles. Color formation increased with
p
H, did not require oxygen, and involved a component that could not be solubilized. The effect was not shown by chemically related neuroactive compounds, such as bufotenine and serotonin, and was antagonized by only tyramine or ethylenediaminetetraacetic acid.
Sex Chromosomes in Lizards
Authors: Cole Charles J. , Lowe Charles H. , Wright John W.
Published: October 2006

Karyotypes of many species of the genus
Sceloporus
support the generalization that there are no morphologically recognizable sex chromosomes in lizards; however, there is a marked sexual dimorphism in the karyotypes of
Sceloporus jarrovi
and
Sceloporus poinsettia
. During meiosis in males, whose diploid number of chromosomes is 31, preferential segregation of chromosomes from a trivalent results in heterogamety.
Molecular Beams with Energies above One Electron Volt
Authors: Abuaf N. , Anderson J. B. , Andres R. P. , Fenn J. B. , Marsden D. G. H.
Published: October 2006

By using as sources supersonic jets of hydrogen or helium containing small concentrations of heavier molecules we have been able to obtain molecular beams with kinetic energies of the heavy molecules well into the range above 1 electron volt. A variety of molecules have been successfully accelerated. Intensities of 10
16
to 10
17
heavy molecules per steradian-second have been achieved at these high energies.